Growing
Growing Brunnera 'Siberian Bugloss' With Forest Gardener Pippa Chapman
IN THIS GUIDE Overview Common Varieties Planting Brunnera Brunnera Plant Care Common Problems Indoor Growing References Brunnera macrophylla, also known by many as ‘Siberian Bugloss’, is a commonly grown garden plant in the UK. Though not native to our shores, it is well-suited to a shaded or partially shaded spot and will generally be untroubled by slugs or snails, unlike hostas and other plants for shade. Brunnera macrophylla is native to woodland ecosystems of the Caucuses and Türkiye.1 It is the best known of a number of species within the Brunnera genus and is certainly the most commonly grown option here in the UK. Particularly prized as ground cover plants for dappled, partial or even deeper shade, many cultivars of this species of Brunnera have been developed, with some prized as foliage plants rather than for their flowers because of their variegated leaves. Overview Botanical Name Brunnera macrophylla Common Name(s) Siberian bugloss Plant Type Perennial Native Area Caucuses and Türkiye Hardiness Rating H6 Foliage Deciduous Flowers Small sprays of bright blue When To Plant May to September Their flowers, while small, are also delightful. A great choice for woodland or forest gardens, Brunnera not only creates good ground cover but also attracts pollinators in the spring, around the same time that these are required for fruit tree pollination. Common Varieties There are numerous varieties of Brunnera that you might grow. One of the ways to narrow down your choices is to look at the Brunnera which have been given an Award of Garden Merit from the RHS: B. macrophylla ‘Hadspen Cream’ Has blue flowers and green leaves that are margined with cream. B. macrophylla ‘Jack Frost’ Known for its silvery green-veined leaves with a frosty appearance. B. macrophylla ‘Looking Glass’ Has silvery foliage with sparse veining in green. B. macrophylla ‘Mister Morse’ Also has silvery leaves but has white flowers too. Planting Brunnera Brunnera can be planted any time from May to September, but planting in late spring or early autumn is ideal. When choosing where to plant them, it is important to think about the amount of sunlight an area receives. Brunnera can cope in the sun as long as the soil has enough moisture, but it will generally do best in dappled, partial or full shade. You can grow Brunnera in the ground in a suitable spot or in a container. When planting, whether in the ground or in a container, the plant should sit at the same level that it was at in its previous pot so that the top of the root system is level with the surface of the growing medium. Firm the soil or growing medium around the new plant and water it in well. Water frequently until the plant becomes well-established. Soil Requirements Brunnera needs moist but free-draining soil or any reasonably fertile peat-free growing medium when grown in a container. These plants do need consistent moisture but, other than this, are not particularly fussy about the soil or medium in which they grow. Growing From Seed Brunnera is not usually a plant that home-growers will cultivate from seed, as most cultivars are purchased as potted plants. “Seed collected from cultivars will often not be true to the parent plant, meaning that most cultivars are best purchased as plants that have been propagated clones,” explains Horticultural Consultant Colin Skelly. “Some cultivars can tend to revert to the species, Brunnera macrophylla, and should be dug up and the reverted sections removed so that this portion does not end up engulfing the usually less vigorous cultivar.” To propagate a Brunnera that you already grow in your garden, root cuttings can be taken in the winter months. Alternatively, plants can simply be lifted and divided in the early spring. However, if you would like to grow Brunnera from seed, it is possible to do so. Often, they will self-seed in ideal conditions, but to take things into your own hands, mix some seeds into a moist potting mix and then place this mix in a plastic bag and pop it in the freezer. Cold stratify the seeds for around 4 weeks. After this, the seed should be sown at temperatures of 16°C and should germinate within 1-3 months. However, germination rates may still be patchy. Brunnera Plant Care Once you have Brunnera growing in your garden, you should find it to be a remarkably easy, trouble-free and low-maintenance addition to your space. Watering Brunnera should, as mentioned above, be well-watered as it becomes established. In many cases, natural rainfall should often be sufficient once the plant has established and you won’t need to think about watering much, if at all. Pruning No pruning is required when growing Brunnera, but you can cut off any brown leaves and deadhead when the autumn arrives if you wish to do so. Dividing While pruning is not necessary, clumps can become overgrown or congested over time, so it is best practice to lift and divide mature Brunnera plants every 3 years or so. Of course, this is also how you will most easily be able to obtain new plants to place elsewhere in your garden. To divide a Brunnera plant, simply lift it using a garden fork. Divide it with your hands or with a spade, before separating and replanting the sections you have created. Make sure that each section or division has roots and you should be able to create a whole bunch of new plants. Common Problems Brunneras don’t tend to have many serious problems and what problems they do have tend to be related to improper placement or care. As long as your plants are in fertile soil that is moist yet free-draining and are not getting too much sun, you should generally find that no great problems arise. Brunnera is notably slug resistant most of the time and it is generally not eaten by browsing animals due to the texture of the leaves. However, Brunnera can still be eaten by pests every once in a while. It is not uncommon to see some leaf damage caused by nematodes, slugs or rabbits if you have these creatures in your garden. Leaves Turning Brown The leaves of a Brunnera plant turning brown is typically a sign of plant stress. Usually, there is an issue with the environmental conditions that cause the leaves on the plant to die and potentially drop off. Brown leaves on Brunnera are most commonly caused by: Dry conditions or underwatering Sunburn (when in too sunny a location) Pests (causing brown patches) Of these three, the first two are the most common, so most of the time, the problem will be easy to address by moving the plant to a more suitable location and making sure that you water more frequently, especially if you are growing your Brunnera in a pot. Invasiveness Brunnera makes good ground cover as it can spread relatively quickly. “Brunnera ‘Alexander’s Great’ is a particularly vigorous, large-leaved cultivar that is ideal for use as ground cover,” adds Colin. This means that where the conditions are ideal, it can have a tendency to take over and may be considered invasive, in the sense that it will outcompete other plants. However, if you lift and divide Brunnera clumps when they are mature, you should not find that these are plants that will get out of control and you should be able to keep them in check. In some areas, they will self-seed where conditions are moist enough, but this is usually of benefit and not a problem in most UK gardens. Indoor Growing Though not typically grown as a houseplant, it is certainly possible to grow Brunnera indoors. The lower light levels indoors are not generally a challenge to these shade-loving plants. However, it is important to make sure that you water enough to keep the growing medium moist (though not waterlogged) at all times. You will also need to keep the plant in a reasonably cool room in your home and ideally not a centrally heated space, which will get too warm and dry. Remember, this is a herbaceous perennial that will die back over the winter months before bursting into new growth in the spring. While it is dormant, the plant should be placed in a garage, shed or other similar location before bringing it back indoors in the late winter or early spring. References 1. Brunnera macrophylla (Adams). (n.d.). Kew Botanic Gardens. Retrieved June 6, 2023, from https://powo.science.kew.org/taxon/urn:lsid:ipni.org:names:113714-1
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Grow Impatiens ‘Busy Lizzies’ As Ideal Bedding Plants By Following These Guidelines
IN THIS GUIDE Overview Common Varieties How To Grow Busy Lizzies Planting Impatiens Busy Lizzies Plant Care Reviving A Dying Impatiens Plant References Busy Lizzies are a shade garden standard and a byword for bedding that produces heaps of charming warm-toned blooms. Impatiens produce masses of colourful little flowers during summer and are a brilliant bedding plant, even more so if your garden is blighted by shade, as these tender little plants will tolerate shady conditions well. As floriferous as these popular annuals are, they also have seriously pretty foliage. Impatiens leaves are very shapely, of an elliptic to lanceolate form, usually slightly serrated and are a rich green shade. Overview Botanical Name Impatiens Common Name(s) Impatiens, Busy Lizzie, Patience Plant, Sultana Plant Type Perennial (annual in temperate regions) Native Area East Africa Hardiness Rating H1B / H1C Foliage Evergreen Flowers Open disk-shaped flower with 5 petals, often notched and overlapping, in tones of orange, red, pink and white, 3-5cm across When To Plant April Although Impatiens are not really annuals, they are effectively annuals in the UK and Europe and are treated as such because they cannot tolerate low temperatures. In their native habitat of eastern Africa, they are actually evergreen perennials.1 Of a bushy, mounding habit that is naturally compact, Impatiens make terrific container plants too. Their small sizes mean small containers, and what better way to keep these herbaceous evergreens going until the following season than by simply bringing the little pots indoors? Gardening expert Dan Ori recommends starting again each year with standard walleriana types as it can be difficult to keep these looking healthy year on year: “More susceptible to cold and dying out, the New Guinea Impatiens actually overwinter in the house well.” Outdoors or indoors, these plants won’t require deadheading as they are self-cleaning.2 Common Varieties Over the past couple of decades, Impatiens in the UK have been struck by a widespread epidemic of downy mildew, specifically, Impatiens Downy Mildew (IDM).3 The devastation was so great that many gardens had to cull their Impatiens and the plant began to be given up on.4 Horticulturists have since developed Impatiens hybrids and cultivar series with resistance to downy mildew.5 In this transitional phase, the classic varieties are available for gardeners alongside the newer series that are mildew-resistant, but I focus on the latter in this guide. The species plant can grow anything from 15-60cm tall with the spread a shade narrower. It bears 5-petalled flowers from 3-5cm in diameter wide which usually occur in shades of pink, purple, orange, red and white. The following series are claimed to be downy mildew-resistant and are available in the UK. I. Accent Series These cultivars are ultra-compact plants growing to only 20cm tall and wide. The flowers are in standard hues, about 5cm across and have a darker eye. Blooming starts earlier and continues for longer. I. SunStanding Series The SunStanding series subsumes various cultivars. These cultivars may be grown under any exposure, in full shade to full sun. I. SunStanding Jazzy Series The Jazzy family features flowers that are very big at about 6cm. Moreover, it has variegated leaves that are yellow in the centre and green at the borders. I. walleriana Imara Series This is an award-winning series with well-branched plants from 25-30cm. The flowers’ hues are especially brilliant and vibrant. I. SunStanding Helios Series These cultivars are a great buy for home gardeners. Although the flowers are not as big as Jazzy’s, it produces them in greater profusion and even has bi-coloured blooms. How To Grow Busy Lizzies Busy Lizzies are easily and often grown from both seeds and cuttings. Impatiens seeds should not be sown directly outdoors in the UK as the favourable season is too short for the plants to mature and flower. Start seeds indoors in trays or small pots about two months before the expected last frost. If you sow in small pots then you will not have to pot on seedlings. Use a seed-starting mix for trays and potting compost amended with perlite or grit for pots. Sow seeds sparsely, 1-1.5cm deep. Dampen the medium and cover the tray or pots with clear polythene or plastic wrap to create humid conditions. The covering should have only a few small perforations. The temperature should range between 20-25°C; dampen daily. After seedlings emerge remove the covering and shift the trays or pots to a spot where they get a couple of hours of morning sunlight, or diffused or filtered sunlight later in the day; otherwise keep them under grow lights. I find that even strong sunlight coming in through patterned glass or frosted glass becomes diffused perfectly for plant-growing purposes. These plants are also super-easy to propagate via softwood cuttings. Hardiness To turn around that term ‘Fully Hardy,’ one might label Impatiens ‘Fully Tender.’ They are rated at H1B and H1C, meaning that the minimum temperatures they can tolerate are, respectively, 10°C and 5°C. So, let alone freezing temperatures or frost, if the mercury dips to even the single digits, the temperature can kill these plants. Though Busy Lizzies are not thought of as houseplants, the truth is that – with only a bit of effort – they make excellent potted plants for the home. Preferred Aspect Though different Impatiens series and cultivars have somewhat varying sun-shade preferences, all will do wonderfully well in partial shade, which is the most suitable position for them. Impatiens should be sited in a sheltered spot. Preferred Soil & Drainage Soil should retain moisture yet drain very well. It should also be fairly rich but not dense. So perhaps Busy Lizzies are a bit fussy about soil! Start with a sandy loam and incorporate grit, perlite, or both to ensure excellent drainage. Mix in organic compost in a 1:3 ratio with the loam and you’re good to go. If you think the soil will dry out very quickly or if you are planting in full sun, then do amend with vermiculite. Planting Impatiens Though you may plant on Impatiens that you have grown from seed or propagated from cuttings, keep in mind that they are conveniently bought as plugs or small potted plants from nurseries and even garden centres. Impatiens may be planted outdoors after the last frost. It would do well to wait until the soil has warmed up to decrease the likelihood of transplant shock and to get the plants off to a good start. In most regions of the UK this would mean sometime in April. For soil considerations please see section Preferred Soil and Drainage. Before planting Busy Lizzies outdoors, harden them by putting the pots outdoors in the morning for four days or so for increasing periods of time. The transplant hole should be about the same depth as the pot and twice as wide. Space the plants by about 30cm. Gently spread out the roots when transplanting. When you backfill the hole ensure that the soil level is no higher on the main stem than it was in the pot. Water in the plant. Please be aware that these plants’ roots are rather delicate so herewith a ‘Handle with Care’ advisory! Busy Lizzies Plant Care Impatiens need regular watering. Do not allow the soil to stay dry, especially in hot weather. At the same time, they also cannot stand waterlogged soil. As they are tender evergreen perennials, open-ground plantings will die in late autumn but you can keep potted plants going year-round by bringing them indoors or moving them to the conservatory, if you have one. For care guidelines if Impatiens are grown as houseplants, please see section Overwintering. A big advantage that these flowering plants have is that they are self-cleaning, so there is no deadheading task. Previously I would pinch the growing tips to head off legginess and ensure compactness but newer cultivars have such a fine bushy and compact habit that even this may not be necessary. Busy Lizzies benefit from fertilising but do not feed them with a balanced formula as it will result in excessive stem and foliage growth. Use a phosphor- and potash-oriented formulation designed for maximising blooms. A slow-release or controlled-release fertiliser (of the above type of formulation) for flowering plants would be perfect. Watering How much water Impatiens need is strongly dependent on their position and the current temperature, besides the amount of rain. For example, if they are sited in full shade and you are experiencing cool days, then a weekly or bi-weekly watering will probably be enough, and if it has rained, then no watering at all. But if they are positioned in full sun and you are having a heat wave and a dry spell, you will need to water them daily. As a general rule, water open-ground Impatiens generously, allow the top centimetre or two of the soil to dry out, and then water again. Overwintering If you choose to overwinter your Busy Lizzies, you need to grow them in containers in the first place. Containers should have drainage holes. Bring them indoors before the temperature falls to the single digits. ‘ Reverse-harden them first. As far as sunlight is concerned, all they’ll need is a few hours of morning sunlight or diffused or filtered sunlight at any time of the day. What is more important indoors are temperature and humidity. A very suitable temperature range is between 13-22°C, and this should not pose any problem indoors. As for humidity, typical indoor humidity is not sufficient for Impatiens plants. Humidity needs to be between 50-70% so a humidifier will prove very useful. To start with you could keep the pots on damp pebbles or orchid trays, mist the plants every other day, and see how it goes. “You are more likely to cause Downy Mildew problems with misting, so watering should be enough,” advises Dan Ori. Water in strict moderation as the plants are not growing actively and water will not dry out as much indoors as it did outdoors. Water sufficiently to make the soil just moist and allow the soil to dry out before watering again. Keep plants away from cold drafts and heating systems. Companion Planting One of the attractions of Busy Lizzies is their willingness and ability to play bridesmaid to the divas among flowering plants. A profusion of uncomplicated Impatiens blooms in bright tones and that rich green foliage in a compact, tidy shape make for a perfect backdrop to taller flowering plants that feature complex, richly-hued blooms. On the other hand, as Impatiens can flourish in shady areas, they become the star attractions when paired with, comparatively duller, foliage-centric evergreens and hedging. For the former type of companion planting, Aquilegia or Columbine is a great choice. Others include Iris and Camellia. I do think that someone should pair Oriental Lily with Busy Lizzies. For the latter type, Ferns and Hostas will be livened up with patches of Busy Lizzies. For entirely different types of effects, try tall, elegant Delphinium among merry little Impatiens, and Hydrangea and Impatiens as ‘pari passu’ companions. Common Problems Impatiens flowers are not only edible, they have a pleasant sweet-vegetal taste. And that is the main ‘common problem’ because everything from voles to deer love to snack on these plants. There is no getting around the reality that if such herbivores are found in your locality, you will have to set up traps or, much better, deterrents and repellants. Like many similar plants, Busy Lizzies can be attacked by aphids and wine weevils. As mentioned, legacy varieties are very vulnerable to downy mildew. Reviving A Dying Impatiens Plant To try to revive a dying Impatiens plant, you need to find out why your plant might be dying. Keep in mind that open-ground Impatiens will die in late autumn because they cannot survive winter in the UK. If a plant is dying during the favourable season, examine the foliage, from which it will be readily apparent if the plant has been afflicted by downy mildew or attacked by herbivores. If you observe a fine whitish down-like coating on the leaves, usually on the undersides, it is downy mildew. If the leaves have been nibbled at and are hole-ridden, you will have to set traps, deterrents or repellants for whatever herbivores are damaging the plant. Outdoors or indoors, Impatiens are susceptible to over and underwatering. In both cases, the trouble will manifest initially as drooping leaves, but in most plants, the result of dry soil will be drooping leaves, while root rot will lead to leaf wilt starting from the upper and outer leaves and progressing downward and inward. Simply check the soil to see if it is dry or soaked and think back to whether and how the plant was watered during the past 10-14 days. While a plant dying from lack of water is easy to save if you act quickly enough, the same cannot be said for a plant affected by root rot. References 1. Impatiens. (n.d.). San Diego Zoo Animals & Plants. Retrieved May 18, 2023, from https://animals.sandiegozoo.org/plants/impatiens 2. Russ, K., & Polomski, R. (2017b, August 26). Impatiens. Home & Garden Information Center | Clemson University, South Carolina. Retrieved May 17, 2023, from https://hgic.clemson.edu/factsheet/impatiens/ 3. Impatiens downy mildew / RHS Gardening. (n.d.). Royal Horticultural Society. Retrieved May 18, 2023, from https://www.rhs.org.uk/disease/impatiens-downy-mildew 4. Impatiens. (n.d.-b). University of Florida, Institute of Food and Agricultural Sciences. Retrieved May 18, 2023, from https://gardeningsolutions.ifas.ufl.edu/plants/ornamentals/impatiens.html 5. Lonnee, D. (2021, May 19). New Downy Mildew Resistant Impatiens Cultivars. Minnesota State Horticultural Society. Retrieved May 18, 2023, from https://northerngardener.org/new-downy-mildew-resistant-impatiens-cultivars/
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Growing Aubrieta - You Can Even Grow This Plant In A Hole In The Wall
IN THIS GUIDE Overview Common Varieties How To Grow Aubrieta Planting Out Ongoing Aubrieta Care Propagating By Division Aubrieta is a no-care evergreen groundcover that easily covers problem spots, tumbles out of crannies and crevices, forms a soft green mat and produces a blanket of brilliant colour during spring. It is a first-rate choice for groundcover, rockeries, edging, planter companions, crannies and crevices and can even be grown in a hole in a wall! Rising only up to 10cm with a spread of 3-4 times its height, this low to no-maintenance evergreen is a great ‘plant-and-forget’ option to fill bare spots and inhospitable patches with year-round foliage of a cool green shade. Overview Botanical Name Aubrieta Common Name(s) Aubrieta, False Rock Cress, Purple Rock Cress Plant Type Perennial Native Area Eastern and Southern Europe Hardiness Rating H6 Foliage Evergreen Flowers Four-petalled, open, disk-shaped, 2cm wide, typically in tones of purple and pink, but also can be white When To Plant April to June and September There’s also that brilliant floral colour from mid-spring through to mid-summer. These mat-forming evergreens push up oodles of cheery little flowers in about the middle of spring. They can bloom in such profusion that, in the flowering season, a bank of Aubrietas will transform from a mat of green to a mat of vivid colour. The flowers are open and disk-shaped with four petals, and usually occur in tones of purple and pink, with white, cream and red hues less commonly seen, but still available. These little blooms are a top draw for butterflies and bees. Common Varieties The majority of Aubrieta varieties and more so the commonly-grown ones, are about 10cm tall and their flowers are typically up to 2.5cm across. A. ‘Doctor Mules’ Below, I’ve listed several varieties that can be sourced without much difficulty: A. ‘Doctor Mules’ (AGM) – This is probably the most widely available and popular variety. Its foliage is of a brilliant green shade and the abundant flowers are of a rich purple colour. A. ‘Royal Blue’ – Belies its name as the flowers are actually mauve-purple. A. ‘Kitte’ – has rich purple to violet flowers. The ‘Kitte’ series has relatively small leaves of a light green shade. This variety has flowers that are bigger than usual and sport a yellow eye. A. ‘Red Cascade’ (AGM) – The ‘Cascade’ series is especially vigorous and has foliage of a bright, deep shade. ‘Red Cascade’ bears flowers of a vivid magenta-red hue. A. ‘Regado White’ – This cultivar has a slow but steady growth pattern and its foliage is relatively hairy and sometimes serrated. The white-white flowers are set off by yellowy-green eyes. A. ‘Argenteovariegata’ (AGM) – This is not as vigorous as some other cultivars. It has soft mauve to lavender flowers but is equally valued for its foliage as the relatively small leaves are variegated in green, yellow and gold. A. ‘Kitte’ How To Grow Aubrieta These plants can easily be grown from seed. Although seeds may be started indoors in trays, this is unnecessary. It is far easier to sow this hardy perennial directly outdoors, assuming you want to grow it in the open ground. April to June is the best timeframe for sowing Aubrieta seeds outdoors. It would be advisable to check the weather forecast so you can sow these seeds when there will be more of a dry spell. Before sowing the seeds, till the soil with a hand hoe or rake. Sprinkle the seeds and cover them with a mere sprinkling of soil, or nudge the seeds partway down into the soil. Do not cover the seeds completely, as they need light to germinate. Water lightly with a watering can that has been fitted with a rose or a sprayer, taking care not to wash away the seeds. Keep the soil moist until the seedlings emerge. Another very reliable way to grow Aubrieta, particularly if you want a copy of the parent plant, is to take and plant semi-ripe cuttings in late summer to early autumn. Hardiness With a hardiness rating of H6, Aubrieta is fully hardy. Even Northern European winters will not affect it, as it can withstand temperatures down to -15°C. Light Requirements Aubrietas prefer a south or west-facing aspect, but they can make do with other less favourable aspects. What is most essential is that they be sited in full sun, which will maximise flowering and also ensure a pleasing, compact shape. They will struggle in partial shade and will fail to thrive in full shade. Preferred Soil Aubrieta grows best in lime-tending soil that is crumbly and not rich that has neutral to slightly alkaline pH. Therefore, a mixed loam of sand, chalk and clay with only a little organic matter is perfect. The soil should drain very well and should not stay damp or continuously moist for long periods of time. Planting Out Aubrietas are fantastic plants to cover bare spots where nothing else worth growing will take root. Such spots include chalky ground, crevices and crannies, verges and slopes, paved walkways, and holes or cavities in and on walls. This plant grows vigorously in many places and it is fairly commonly seen in the UK. Aubrietas often form an undulating mat atop walls and sometimes make a cascading vertical blanket along walls, as these unfussy, lime-loving plants grow in clumps in cracks and crevices. Young plants and seedlings may be transplanted into any of the inhospitable spots mentioned above. Simply get rid of any loose stones or weeds, fill in with soil, transplant the young plant and water it in. “I like to plant aubrieta in winter-spring hanging baskets to give one final eruption of colour before the display is swapped for summer plants,” shares Master Horticulturist Peter Lickorish. “From these baskets, after flowering, the aubrieta can be trimmed by a third and transplanted into a small planting pocket, or even the front of a border.” Ongoing Aubrieta Care Aubrieta is a seriously low-care plant. Other than the simple type of pruning outlined below, you may wish to feed established plants with a very light helping of organic fertiliser oriented to lime-loving flowering plants at the beginning of spring. None of this is necessary, as this plant flourishes in what are usually considered poor soils. Watering Water young plants regularly but do not soak the soil entirely and be sure it drains well. When watering mature plants, allow them to fully dry out before watering again. In many regions of the UK, you will not need to water these plants at all during the wet seasons. Established plants are drought-tolerant, but make sure that watering duties are not completely disregarded during any long stretch of dry weather. Pruning Aubrieta does not need any pruning, but it might be helpful to cut it back to maintain a compact size, especially if you have grown it in a wall, cranny or rockery. Such a cutback may be done anytime from the end of the flowering season to early autumn, but not any later. Cut back 25-50% of the plant. Aubrietas will become unkempt and straggly after three years or so, more so if positioned in partial shade, so this type of pruning will maintain a neat look. Common Problems In the UK, the only pests that the vast majority of Aubrieta cultivars are susceptible to are aphids and flea beetles. Both fall in the category of a garden nuisance rather than any serious menace and both are fairly easily controlled with biological controls and natural remedies. They can also succumb to powdery mildew, though this strikes these plants infrequently and can be treated fairly easily. Propagating By Division Aubrieta is not typically propagated by division because it does not spread aggressively and there is little reason to disturb the mat-forming groundcover it gradually produces. That said, its clumps can certainly be divided and re-planted. “The only caution is to check that clumps have roots,” adds Peter. “It is surprising how far the stems of this plant can spread from the original base and roots of the plant.”
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Dahlia Watering Requirements Can Be Contentious - Here's What The Experts Say
IN THIS GUIDE How Much Water Do Dahlias Require? When To Water Dahlias The Watering Process Dahlias are popular plants to grow in UK gardens. These cottage garden favourites are relatively easy to grow as long as they are grown in the right location. “At the moment I am obsessed with dahlias and can’t get enough of them,” shares Florist Simon Lycett. However, they do have to be cared for correctly and one important element of their care is watering. Dahlias are not necessarily difficult flowers to grow and getting the watering right can be an important piece of the puzzle – read on to understand clearly just what your dahlia will need. Difficulty Easy Equipment Required Watering can or hose When To Water Throughout the year, especially during the summer How Much Water Do Dahlias Require? One important thing to understand when growing dahlias is that they do need consistent moisture and plenty of water throughout the summer season once they are mature. Another detail to remember is that dahlias like moist but not waterlogged growing medium. Maintaining this consistent water availability is a key component in growing these plants successfully. However, the water needs of dahlias will differ throughout the year and will depend on the location of the particular garden in which they are grown. “For dahlias planted in the ground, the soil conditions will play a key part in how often you’ll need to water your dahlias in hot, dry weather,” shares Master Horticulturist Colin Skelly. “Dahlias in sandy soil will need far more watering than those in clay soils, which hold more soil moisture for longer.” How much you will need to water will also depend on how much rainfall there is in your area and on the light levels, temperature and other environmental factors. The size and age of the plants will be important too, as June Nash from The National Dahlia Society explains: “Water sparingly at first but gradually increase this as the plant grows. “Each pot will eventually need to be watered every day, usually in the evening, even if it has rained.” You’ll also have to consider whether you are growing your dahlias in containers or in the ground. Plants in containers will generally need to be watered a lot more frequently. When growing in the ground where you live, you’ll need to understand the soil type and other soil characteristics because some soils retain water a lot more easily than others. “A good free draining compost is essential and I personally had some very good results with Dahlias in pots last year using peat-free compost,” says David Hall, the Nursery Manager at Halls of Heddon. “Dahlias need plenty of water without getting waterlogged – they won’t like that!” When To Water Dahlias Mature dahlias should be watered when the top few centimetres of the soil or growing medium feels dry. However, it is best when you are planting dahlias to avoid excessive watering too early. Tubers can easily rot if they are in saturated soil or growing medium. Don’t water unless the soil or medium is very dry. Wait until the roots have formed and become well-established before you start to water during dry periods. Once your dahlia has established a good root system, water consistently when the weather is dry and pay attention to drainage, ensuring that while moisture remains, the soil does not become saturated and excessive water can drain away. The Watering Process When you are watering your dahlias, it is important to remember that fewer deeper waterings are better than providing water little and often. This helps the plants develop deeper, healthier roots. How you water is also important, as well as the quantity and regularity of watering. One other important thing to think about when watering dahlias is where the water is actually required. Rather than sprinkling water from above, which soaks the foliage and flowers of your dahlias, think about how you can direct the water to where it is actually required. Water the soil at the base of the plant rather than the plant itself, so that the water can be taken up from the soil by the roots of your plant. Try to keep splashes onto the foliage and flowers to a minimum. By thinking about the above, you should be able to keep dahlias happy when it comes to their water needs.
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Hosta Nursery Managers Share Their 20 Favourite Varieties To Grow
IN THIS GUIDE Expert Picks 1) Hosta ‘Allan P. McConnell’ 2) H. ‘Captain Kirk’ 3) H. ‘Cathedral Windows’ 4) H. ‘Devon Green’ 5) H. ‘Fireworks’ 6) H. ‘Forbidden Fruit’ 7) H. ‘Fragrant Bouquet’ 8) H. ‘Guacamole’ 9) H. ‘Gypsy Rose’ 10) H. ‘Hadspen Blue’ 11) H. ‘Niagara Falls’ 12) H. ‘Night Before Christmas’ 13) H. ‘Patriot’ 14) H. ‘Regal Splendor’ 15) H. ‘Sum And Substance’ 16) H. ‘Summer Music’ 17) H. ‘Victory’ 18) H. ‘War Paint’ 19) H. ‘Wide Brim’ 20) H. ‘Yellow River’ Other Notable Varieties Hostas can be excellent choices, often ideal for the shady spots in your garden you might otherwise fail to fill. They come in different colours, shapes and sizes, with cultivars too numerous to possibly give a complete list. However if you are looking for an interesting hosta for your garden, you might find the right one for you in my list of highly regarded options below. Expert Picks Before we get to my favourites, I asked some expert hosta plant nurseries about their favourite hosta varieties. “There are so many varieties, it is difficult to pick a favourite!” says John Plant, the Owner of Rewela Hostas. “I love Hostas ‘Hudson Bay’ because of the colour of the foliage and its size, but it is slow-growing. “Good standard varieties like Hosta ‘Liberty’ are up there with varieties like Hosta ‘June’, as they are always reliable, great to look at and easy to grow.” H. ‘Liberty’ Ollie Walker, the Nursery Manager at Sienna Hosta, also finds choosing one favourite a challenge: “At the nursery, we all have our favourites and these change every year as we collect more new and exciting varieties. “Hosta ‘First Blush’ has to be mentioned, as this variety has a stunning red colour up the stem and through the leaf and is a very interesting new hosta. “Another variety that is worth a mention is ‘Amalia’, as this large variety has bright yellow leaves and a wonderful green rippled pie crust margin.” Barry Ankney, from the American Hosta Society, previously owned a specialist hosta nursery and shared an extensive list of his favourites: ‘Autumn Frost’ “This variety emerges in spring with powder blue leaves and bright yellow margins,” he says. “The margin of the leaf gradually fades to white during the season. “This is a truly magnificent hosta and striking specimen plant that holds its colouration well into the autumn.” ‘Rainforest Sunrise’ “The leaves of this cultivar are solid green when they emerge, then quickly develop dramatic dark green borders and radiant gold centres,” shares Barry. “The thick slug-resistant leaves are heavily corrugated and cupped.” ‘June’ “This hosta is consistently number one in the popularity polls and for good reason; it’s a must-have. “It forms a perfect mound of gold leaves with a wide blue-green margin. “There is a third lighter green colour between the margin and centre of the leaf that often streaks to the midrib.” ‘Sagae’ “Spectacular large blue-green leaves with variations of creamy white on the margins make this hosta stand out in any garden setting,” says Barry. “The leaves are frosty blue in spring with a feathered yellow margin, whilst grey-green streaks are painted in the area between the centre and the margin.” Believe it or not, that’s not all. “We have over 550 varieties of hosta in our collection, and all have their own unique qualities,” shares Robert Barlow, from North Staffordshire Hostas. Some of his favourite varieties include: Miniature H. ‘Blue Mouse Ears’ ‘Lime Fizz’ ‘Hydon Sunset’ ‘Blue Mouse Ears’ Small to Medium ‘Toy Soldier’ ‘Hands Up’ Large H. ‘Dream Queen’ ‘Patriot’ ‘Sagae’ ‘Dream Queen’ Giant ‘Krossa Regal’ ‘Empress Wu’ ‘Sum & Substance’ See our list of hostas below – we believe each to be a great place to start if you’re looking to grow a variety in your garden here in the UK. 1) Hosta ‘Allan P. McConnell’ COMMON NAME(S): plantain lily ‘Allan P. McConnell’ HARDINESS RATING: H7 FOLIAGE COLOURS: white and green FLOWERS: purple SIZE: 0.1-0.5m in height, 0.1-0.5m spread Producing a mound of deep green ovoid leaves 8cm in length, each one with narrow white margins, this option also has bell-shaped purple flowers which are produced on stems around 40cm tall in mid to late summer. 2) H. ‘Captain Kirk’ COMMON NAME(S): plantain lily ‘Captain Kirk’ HARDINESS RATING: H7 FOLIAGE COLOURS: green and yellow FLOWERS: purple SIZE: 0.1-0.5m in height, 0.5-1m spread This clump-forming deciduous perennial grows to around 50cm in height. The leaves are broadly ovoid with ribs and are lightly puckered. The foliage is deep green and each leaf has a vivid yellowy-green splash across the centre. Pale purple flowers grow on upright stems in the summer months. 3) H. ‘Cathedral Windows’ COMMON NAME(S): plantain lily ‘Cathedral Windows’ HARDINESS RATING: H7 FOLIAGE COLOURS: green and yellow FLOWERS: white SIZE: 0.1-0.5m in height, 0.5-1m spread Looking almost like stained glass, the leaves of this hosta are rounded and ribbed, with interesting variegation. The leaves have wide deep to mid-green margins and central splashes of greenish yellow. The flowers, which are fragrant, are white. These are held above the foliage on erect stems in the summer months. 4) H. ‘Devon Green’ COMMON NAME(S): plantain lily ‘Devon Green’ HARDINESS RATING: H7 FOLIAGE COLOURS: green SIZE: 0.1-0.5m in height, 0.5-1m spread Growing around 50cm tall and 60cm wide, this hosta has shiny dark green leaves which are around 15cm long with fairly prominent ribbing. These plants are largely grown for their foliage but also have attractive little tubular flowers in late summer and early autumn. These are a pale purple hue, with darker stripes on them. 5) H. ‘Fireworks’ COMMON NAME(S): plantain lily ‘Fireworks’ HARDINESS RATING: H7 FOLIAGE COLOURS: white and green FLOWERS: purple SIZE: 0.1-0.5m in height, 0.1-0.5m spread This little hosta needs plenty of light – though no hot sun – and regular feeding to perform at its best. It has twisty leaves which are mostly white or creamy green, with dark green edging. Though it can be happy in a container, it should not be restricted to ones that are overly small. The flowers, which appear in July, are pale lavender hue. 6) H. ‘Forbidden Fruit’ COMMON NAME(S): plantain lily ‘Forbidden Fruit’ HARDINESS RATING: H7 FOLIAGE COLOURS: green and yellow FLOWERS: purple SIZE: 0.5-1m in height, 0.5-1m spread Another hosta with variegated leaves, this option can potentially grow up to 1m tall and wide. It has broad leaves which are yellow to pale orange in the centres and dark green to blue around the outsides. The flowers are lavender in hue and borne on the upright stems above the foliage in the summer. 7) H. ‘Fragrant Bouquet’ COMMON NAME(S): plantain lily ‘Fragrant Bouquet’ HARDINESS RATING: H7 FOLIAGE COLOURS: green and cream FLOWERS: white SIZE: 0.5-1m in height, 0.5-1m spread This clump-forming perennial grows to around 45cm tall. It has leaves which are broad, oval and slightly twisted; each one bright green with a creamy margin and deeply set veins. As the name of this cultivar suggests, the flowers are borne in loose clusters. They bloom in summer on upright stems that can reach almost 1m in height, are pale purple in colour and are fragrant too. 8) H. ‘Guacamole’ COMMON NAME(S): plantain lily ‘Guacamole’ HARDINESS RATING: H7 FOLIAGE COLOURS: yellow and green FLOWERS: purple and white SIZE: 0.5-1m in height, 0.5-1m spread A small to medium-sized hosta, this option has large golden yellow to light green leaves which are large, puckered and have somewhat darker edges. Above these mounds of leaves, fragrant white to lavender flowers are produced over the summer months. “I think ‘Guacamole’ is a great choice for a tall container near a doorway, as you can enjoy the flowers and their scent,” shares Dan Ori, a Horticultural Consultant. 9) H. ‘Gypsy Rose’ COMMON NAME(S): plantain lily ‘Gypsy Rose’ HARDINESS RATING: H7 FOLIAGE COLOURS: green, yellow and white FLOWERS: purple SIZE: 0.1-0.5m in height, 0.5-1m spread Growing to around 40cm tall, this hosta has broad, rounded, dark green leaves, each of which has a broad streak of pale yellow at the centre, with some thin flashes of white at the centre. Purple flowers are also produced on these plants on upright stems in summer. 10) H. ‘Hadspen Blue’ COMMON NAME(S): plantain lily ‘Hadspen Blue’ HARDINESS RATING: H7 FOLIAGE COLOURS: greeny-blue FLOWERS: purple SIZE: 0.1-0.5m in height, 0.5-1m spread The leaves on this impressive hosta have a distinctive silvery-blue sheen. They are thick and markedly textured, more or less heart-shaped in form. This is a small and slow-growing hosta which forms clumps around 25cm high. The bell-shaped purple flowers are definitely not the stars of the show for this foliage plant, but these bloom on erect stems in the summer. 11) H. ‘Niagara Falls’ COMMON NAME(S): plantain lily ‘Niagara Falls’ HARDINESS RATING: H7 FOLIAGE COLOURS: green FLOWERS: purple SIZE: 0.1-0.5m in height, 0.5-1m spread This hosta grows around 1m across and 0.5m in height. Its heart-shaped leaves are green and have deep ribs running down them. They also have distinctive wavy edges, creating the waterfall effect, and tips that turn downwards at the ends. Loose clusters of pale purple flowers are produced on leaning, leafy stems in the summer. Another H7 hardy cultivar. 12) H. ‘Night Before Christmas’ COMMON NAME(S): plantain lily ‘Night before Christmas’ HARDINESS RATING: H7 FOLIAGE COLOURS: green and white FLOWERS: purple SIZE: 0.1-0.5m in height, 0.5-1m spread Growing to around 45cm high, this hosta has ovate leaves which are tapered towards the ends. These leaves are deep green, with a narrow creamy streak down the centre of each one. The stems are white-streaked too. The flowers, pale purple, cannot live up to the foliage but are pretty nonetheless, held on the upright stems in summer. 13) H. ‘Patriot’ COMMON NAME(S): plantain lily ‘Patriot’ HARDINESS RATING: H7 FOLIAGE COLOURS: green and cream FLOWERS: blue and purple SIZE: 0.5-1m in height, 0.5-1m spread Clump-forming and perennial, this cultivar grows to around half a metre tall. The ovate leaves are puckered and ribbed, with irregular cream margins and mid-green centres. The foliage will remain through spring, summer and autumn, and in summer, the plants will also boast their spikes of funnel-shaped flowers, which are a lavender blue hue. 14) H. ‘Regal Splendor’ COMMON NAME(S): plantain lily ‘Regal Splendor’ HARDINESS RATING: H7 FOLIAGE COLOURS: green, silver, green and cream FLOWERS: purple and pink SIZE: 1-1.5m in height, 0.5-1m spread This hosta is large and dramatic, with deeply ridged deep blue-green leaves which have narrow margins around the edges of a creamy yellow hue. The edges become more creamy and lighter as the leaves mature. The bell-shaped flowers form above the leaves in the late summer and they are a pale lavender pink in colour. 15) H. ‘Sum And Substance’ COMMON NAME(S): plantain lily ‘Sum and Substance’ HARDINESS RATING: H7 FOLIAGE COLOURS: green and yellow FLOWERS: purple SIZE: 0.5-1m in height, 0.5-1m spread Heart-shaped leaves of a bright, vivid, yellowy-green colour set this hosta apart from many others. The large leaves stand out in partial shade. The foliage of this plant is definitely the main attraction, but the bell-shaped flowers also add interest, growing on stems 75cm long in the summertime. 16) H. ‘Summer Music’ COMMON NAME(S): plantain lily ‘Summer Music’ HARDINESS RATING: H7 FOLIAGE COLOURS: green, cream, yellow and white FLOWERS: purple SIZE: 0.1-0.5m in height, 0.5-1m spread Another hosta with leaves that stand out very well in lower light areas, ‘Summer Music’ has leaves that are light green on the sides with central markings that start out pale green and change to a purer white as the leaves mature. Some leaves also have streaking along the sides of this central area in pale green or gold. Lavender flowers bloom in loose clusters on upright stems in the summer. 17) H. ‘Victory’ COMMON NAME(S): plantain lily ‘Victory’ HARDINESS RATING: H7 FOLIAGE COLOURS: green, silver and green FLOWERS: purple SIZE: 1-1.5m in height, 1-1.5m spread The large heart-shaped leaves on this herbaceous perennial are a glossy greyish-green, with deeply incised veins and pale yellow variegation along the edges. The flowers are a very pale purple and these are produced on tall stems that can reach up to 1.5m in height. The plant can also spread to around 1.5m over time. 18) H. ‘War Paint’ COMMON NAME(S): plantain lily ‘War Paint’ HARDINESS RATING: H7 FOLIAGE COLOURS: cream and green FLOWERS: purple SIZE: 0.5-1m in height, 1-1.5m spread This hosta can grow to around 90cm tall, with a spread of 1-1.5m. Its heart-shaped leaves are rippled along the edges, with irregular variegation while the leaves are young. The centres of the young leaves can be cream to pale green and the margins are a deeper green, but this central area darkens as the leaves grow and by the middle of summer, the leaves are typically solid green. Lavender flowers are borne on upright stems in the summer. 19) H. ‘Wide Brim’ COMMON NAME(S): plantain lily ‘Wide Brim’ HARDINESS RATING: H7 FOLIAGE COLOURS: green and yellow FLOWERS: purple SIZE: 0.1-0.5m in height, 0.5-1m spread The leaves of this hosta are broadly heart-shaped and dark greeny-blue but with broad margins of creamy yellow around the outside of each leaf. Stems around 60cm tall bear funnel-shaped flowers with a lavender hue in the summer months. 20) H. ‘Yellow River’ COMMON NAME(S): plantain lily ‘Yellow River’ HARDINESS RATING: H7 FOLIAGE COLOURS: green, cream and yellow FLOWERS: purple SIZE: 0.5-1m in height, 0.5-1m spread This hosta has large green heart-shaped leaves enlivened by ridging and creamy yellow margins which are slightly ruffled along the sides. The bell-shaped flowers bloom in summer on thin, upright stems above the interesting foliage. Of course, I couldn’t possibly list all the great hostas that you might grow in just one article. However, all of the highly regarded hostas listed above could be great options for your garden. Other Notable Varieties H. ‘Devon Blue’ COMMON NAME(S): plantain lily ‘Devon Blue’ HARDINESS RATING: H7 FOLIAGE COLOURS: silver, blue, green and grey FLOWERS: purple SIZE: 0.1-0.5m in height, 0.5-1m spread H. ‘Invincible’ COMMON NAME(S): plantain lily ‘Invincible’ HARDINESS RATING: H7 FOLIAGE COLOURS: green FLOWERS: purple and white SIZE: 0.1-0.5m in height, 0.1-0.5m spread H. hypoleuca COMMON NAME(S): white-backed hosta HARDINESS RATING: H7 FOLIAGE COLOURS: green FLOWERS: purple SIZE: 0.5-1m in height, 1-1.5m spread H. ‘Paul’s Glory’ COMMON NAME(S): plantain lily ‘Paul’s Glory’ HARDINESS RATING: H7 FOLIAGE COLOURS: blue, cream, green, yellow FLOWERS: purple SIZE: 0.5-1m in height, 0.5-1m spread Hosta sieboldiana var. sieboldiana COMMON NAME(S): giant blue hosta HARDINESS RATING: H7 FOLIAGE COLOURS: green FLOWERS: white SIZE: 0.5-1m in height, 0.5-1m spread H. ‘Abba Dabba Do’ COMMON NAME(S): plantain lily ‘Abba Dabba Do’ HARDINESS RATING: H7 FOLIAGE COLOURS: green and gold FLOWERS: purple SIZE: 0.5-1m in height, 1-1.5m spread H. ‘Golden Sunburst’ COMMON NAME(S): plantain lily ‘Golden Sunburst’ HARDINESS RATING: H7 FOLIAGE COLOURS: green FLOWERS: white SIZE: 0.5-1m in height, 0.5-1m spread H. ‘Midwest Magic’ COMMON NAME(S): plantain lily ‘Midwest Magic’ HARDINESS RATING: H7 FOLIAGE COLOURS: green FLOWERS: purple SIZE: 0.1-0.5m in height, 0.5-1m spread H. ‘Antioch’ COMMON NAME(S): plantain lily ‘Antioch’ HARDINESS RATING: H7 FOLIAGE COLOURS: green, cream and white FLOWERS: purple SIZE: 0.1-0.5m in height, 0.5-1m spread H. fortunei var. aureomarginata COMMON NAME(S): gold-edged plantain lily HARDINESS RATING: H7 FOLIAGE COLOURS: green and yellow FLOWERS: purple SIZE: 0.5-1m in height, 0.5-1m spread H. ‘Helen Doriot’ COMMON NAME(S): plantain lily ‘Helen Doriot’ HARDINESS RATING: H7 FOLIAGE COLOURS: green FLOWERS: white SIZE: 0.5-1m in height, 1-1.5m spread
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Specialist Rose Growers Share 9 Common Growing Problems And Their Solutions
IN THIS GUIDE 1) Aphids 2) Black Spot 3) Dieback 4) Leaf-Rolling Sawfly 5) Powdery Mildew 6) Root Problems 7) Stem & Branch Problems 8) Problems With Leaves 9) Problems With Rose Flowers References Roses are among our favourite plants here in the British Isles and for good reason. They are great for many of our gardens, can be relatively low maintenance, they smell wonderful and also attract plenty of beneficial wildlife to our outside spaces. Most of the time, roses planted in the right places in our gardens can thrive with little work and with not that much attention from us. However, as with all plants, there are certain common problems that can arise when growing roses in your garden, no matter which of the many species and cultivars you grow. The most common problems encountered when growing roses in the UK are: Aphids – small insects that cover the plant, sucking sap from stems, leaves and flowers. Rose black spot – a fungal issue identifiable via dark spots on the leaves of the plant. Rose dieback – another fungal issue which can cause visible damage or decay. Leaf rolling sawfly – sawflies which excrete chemicals that cause leaves to curl up. Powdery mildew – white powdery growth on the surface of leaves, which can inhibit growth. Root problems – decay of the roots, commonly caused by waterlogged conditions. Stem and branch issues – bumps or masses on the stems or branches of roses are commonly caused by crown gall or scale insects. Leaf discolouration, curling or wilting – could be caused by any number of insects or fungal issues. Rose blindness – a failure to flower, often caused by the plant being grown in too shady an area. We dissect each of these issues in more detail below: 1) Aphids Aphids can weaken roses by feeding on their sap and can also lead to the formation of sooty mould which affects the appearance of the plants.1 While a few aphids on roses are not usually an issue at all, a serious infestation can potentially become a problem. The best way to deal with aphids in any organic garden is to keep their numbers in check by attracting plenty of creatures that eat aphids, like ladybirds and lacewing, to keep their population down. “An alternative solution is to spray with something to kill the aphids,” shares Dan Ori, a Horticultural Consultant. “A homemade solution like a weak mix of non-bio washing up liquid could be applied directly onto the aphids to suffocate them. “It is important to note that when you spray it can be indiscriminate and you may harm other wildlife or the environment in the process.” 2) Black Spot This is a serious fungal disease affecting rose leaves. When this problem arises, deep purple or black spots develop on the leaves of a rose plant and these will then often drop off earlier than they should. “If there is an attack of blackspot, it usually starts after the first flush of flowers, when the plant has been expending lots of energy producing blooms,” says Philip Harkness, an expert rose breeder and the Owner of Harkness Roses. Sadly, badly affected plants can shed almost all of their leaves. While we can delay the onset of this problem and reduce its spread somewhat by removing affected material quickly and pruning out affected stems and leaves, spores can still blow in from elsewhere, so it is difficult to eliminate this issue altogether. Older species rose types are not as badly affected and are therefore better choices for areas where this is a persistent problem. “Apart from variety selection and removal of infected material, you can thin out any dense growth to allow more airflow,” says Dan. “Ultimately, the only control I have ever found to work effectively is to spray a fungicide.” 3) Dieback Some degree of branch or stem dieback on roses is widespread and seen in most gardens. However, in some areas, it can become a much more damaging issue. Rose dieback can occur due to: Planting roses where other roses were grown before. Fungal problems. Root damage or decay. Physical damage to branches. Severe insect infestation. Frost damage to young shoots in early spring. Poor pruning. Dieback can then lead to further fungal issues and common diseases arising from it include grey mould and rose canker, which can find opportunities where existing damage is found. 4) Leaf-Rolling Sawfly This sawfly causes the leaves on roses to roll up tightly, which mimics the damage that can be done to roses by weedkillers. Female sawflies insert eggs into rose leaflets, secreting chemicals that cause the leaves to roll.2 After some time, larvae hatch from these eggs and feed from inside the rolled-up leaves. Typically, roses can withstand this and suffer no lasting damage due to these insects, so it is best to treat this pest as part of the natural biodiversity of your garden. 5) Powdery Mildew Among the many fungal issues to which roses can fall prey, powdery mildew, with its conspicuous white growth on foliage, stems and flowers is another of the most common. This problem can be unappealing and affect the visual beauty of your roses. When a rose succumbs repeatedly and heavily to this problem, the plant’s vigour can be reduced. Making sure that the environmental conditions are optimal for the roses that you are growing and ensuring good air circulation around your plants can help reduce the chances of a severe infection taking hold. Ensuring healthy soil, feeding to promote strong growth and managing humidity by spacing and pruning correctly are all also important in helping to reduce the chances of this problem occurring or becoming severe. 6) Root Problems If there is a decay of the roots of a rose, this can be due to an attack by several different diseases or simply a result of drainage issues that have led to waterlogging. Occasionally, hard frosts can cause root death on roses kept in containers. One disease that can affect both roses in containers and those in the ground is Phytophthora root rot. This is unfortunately quite a common problem. In the soil, roses are also unfortunately one of many plants susceptible to honey fungus. If a rose is newly planted in an area where there were roses before, it may fail to root out as it should. This is a problem called Replant Diseases, sometimes referred to as ‘rose sickness’.3 If this is the case, these plants will not establish well and will lack the thin and delicate feeder roots that they should have. It is best to avoid potential pathogens or pests and change out the topsoil in an area or, better yet, plant roses elsewhere where they have not previously been grown. Chris Styles from Style Roses elaborates on this problem: “If you continue to get disease issues with particular roses year after year, dig them up and dispose of them,” says Chris. “Then, replace with new ones and use Mycorrhizal fungi granules (Rootgrow) at the time of planting to prevent rose replant sickness.” 7) Stem & Branch Problems We have already discussed some of the many potential causes of stem and branch dieback of roses, which, as mentioned above, is fairly common on a smaller scale. “As with any living organism, roses may suffer an attack and fungi (blackspot, mildew and rust) are the most common adversaries,” says Philip. Dieback pathogens can worsen existing issues and exacerbate any problems. If you see a large knobbly mass at the base of the stem on a rose, this is likely to be a bacterial disease called crown gall. As a result of this problem, the roots can also be impacted. If the branches and stems on a rose feature small, brown bumps that look like limpets, you are looking at an infestation of scale insects. Brown scale is most common on roses and one called scurfy rose scale also affects the stems, leaving round, flat, whitish markings. 8) Problems With Leaves A whitish-grey powdery growth on the leaves of a rose is powdery mildew. If rose leaves are sticky, shiny and have a black growth, this is down to aphids, honeydew and sooty mould. Aside from these things, there are also other issues with leaves on roses that might arise. For example, if large larvae are eating the leaves, this could be a large rose sawfly. If leaves have neat semi-circular or oval holes, this could be leaf-cutter bees. If there are large yellow spots on the top of leaves and orange dots beneath, this is rose rust, which is a fungal infection. The orange pustules will be replaced by black ones in the late summer or autumn. If leaves are discoloured, small and thin, this could be due to a viral infection or, more commonly, a result of contamination with glyphosate (a weedkiller) the season prior. 9) Problems With Rose Flowers If most of the branches on a rose fail to flower, this is often the result of rose blindness. This is a poorly understood disorder that diverts the plant’s energy so that it fails to produce blooms. The cause is unknown, but weather conditions might be involved or it might be due to the plant being grown in too shady an area. Proper pruning, fertilising, mulching and ensuring roses are in a sunny and open position may help. References 1. Townsend, L. (n.d.). Aphids. Entomology at the University of Kentucky. Retrieved April 4, 2023, from https://entomology.ca.uky.edu/ef103 2. Rose leaf-rolling sawfly. (n.d.). Royal Horticultural Society. Retrieved April 4, 2023, from https://www.rhs.org.uk/biodiversity/rose-leaf-rolling-sawfly 3. Replant Disease. (2020, January 1). Science Direct; Elsevier BV. https://doi.org/10.1016/b978-0-12-818732-6.00023-x
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"I Use A Net To Catch The Seeds" - Euphorbia Propagation Advice From Darren Evans
IN THIS GUIDE 1) Growing Euphorbias From Seed 2) Propagating From Softwood Cuttings 3) Dividing Euphorbias References Euphorbias are varied plants that like a wide range of conditions and differ greatly in their growth habit and appearance. Some are great for growing outdoors in gardens in the UK, while others are prized as houseplants or for greenhouse growing. Euphorbias are propagated in a number of different ways. They can be: Grown from seed. Propagated by means of softwood cuttings. Propagated by division. Whichever method you are looking at for the particular type of euphorbia that you want to grow, the job is typically one to undertake in the spring. Difficulty Easy to medium Equipment Required Euphorbia seeds (sowing), suitable growing medium, gardening gloves, pots, garden fork (dividing) When To Propagate Spring 1) Growing Euphorbias From Seed Species types of Euphorbia can be grown from seed, as Darren Evans from Pugh’s Cacti explains: “Euphorbias have male and female plants and, once pollinated, produce a seed that explodes to scatter their seeds,” he says. “In my greenhouse, I use a net to catch the seeds, tying the net around the plant until the seeds appear.” However, it is important to remember that cultivars will not come true to seed. In other words, the baby plants you grow will not necessarily resemble the parent plant and can differ in their growth habit or colour. This is typically the method used to grow annual Euphorbias like E. marginata and some other species. When To Sow The seeds from many Euphorbias can be collected when the seed capsules turn brown. These seeds can then be sown in autumn or in spring. Sowing Euphorbia Seeds Collect or source your euphorbia seeds. Prepare a seed tray and your growing medium. Soak your euphorbia seeds for a few hours before sowing to improve results. Sow seeds on the surface of a seed-starting growing medium and lightly cover them with more of the growing medium. Be patient as germination can take several months, especially in cooler conditions. Wearing gloves, pot on as needed. Often, plants will then be ready to plant out in a couple of years. 2) Propagating From Softwood Cuttings Another option with some Euphorbias is to propagate an existing plant by means of softwood cuttings. Shrub-like Euphorbias, including those with biennial stems that grow one year before flowering the next, can be propagated by means of softwood cuttings. Some Euphorbias that are suited to this method of propagation include E. characias and related plants E. mellifera and E. myrsinites. When To Take Softwood Cuttings Softwood cuttings from Euphorbias are best taken in the early spring. You should select the short shoots that emerge at the base for this purpose. Growing Euphorbia From Softwood Cuttings Select young, pliable green shoots from the base of the plant in early spring. Remove 5-10cm of the shoot, cutting the young shoots from the plant just above the ground, as close to the base as possible. Pinch out the tip of the softwood cutting with snips. Dip the base into a rooting hormone for the best chances of successful rooting. Pot up cuttings into containers filled with cuttings compost, watering well but making sure excess water can drain away freely. Grow on in a warm location, out of direct sunlight until the roots form well. After 2-4 weeks, cuttings should have rooted and be ready to harden off and pot on. 3) Dividing Euphorbias A final option suitable for the propagation of certain Euphorbias is to lift and divide your plants to obtain more of the same for your garden. This is by far the easiest way to propagate Euphorbia and it is suited to a large number of these plants. The euphorbias that are suited to propagating in this way are those that are herbaceous and clump-forming. When To Divide The best time to divide most Euphorbia that can be propagated in this way is in the spring, just as the plants come into growth in the early spring, or just after flowering in late spring for the earliest flowering types. How To Divide Euphorbia Lift a mature clump-forming herbaceous Euphorbia from the soil with a garden fork. Give the clump a gentle shake to remove clods of soil, so the roots can be seen clearly. Ease the plant apart to create several sections of root with a little top growth. These sections or divisions can be potted up or planted elsewhere in your garden. It is important to remember that different methods of propagation are suited to different types of Euphorbia, so it is important to choose a propagation method that is suited to the specific euphorbia that you have chosen to grow. This is a genus of over 2,000 species of plants – each of which has its own specific growing requirements.1 References 1. Euphorbia L. (n.d.). Kew Royal Botanic Gardens. Retrieved April 6, 2023, from https://powo.science.kew.org/taxon/urn:lsid:ipni.org:names:327729-2#children
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Prune Euphorbia Soon After Flowers Fade In Early Autumn, Argue These Experts
IN THIS GUIDE Do You Need To Prune Euphorbia? Prune Once Flowers Fade Pruning Evergreen Euphorbias Pruning Euphorbias With Biennial Stems Pruning Herbaceous Perennial Types Euphorbias are varied plants within the same genus that can require rather different growing conditions and care. When thinking about any element of euphorbia care, it is important to consider which specific type and variety you are growing. Understanding the specific environmental preferences and needs of your specific euphorbia can be important when it comes to placement, watering and more. Pruning is another key area where there are no general rules and we need to look more specifically in order to determine what to do. Difficulty Medium Equipment Required Secateurs, pruning shears or gardening scissors, gardening gloves When To Prune Summer or autumn Do You Need To Prune Euphorbia? Whether or not you need to prune Euphorbias very much depends on which type and variety you are growing. Some euphorbias do not need to be cut back or pruned at all, whilst others will perform best if pruned or cut back correctly. Euphorbia is a large genus including some plants which are shrub-like with a permanent framework of branches; some which are herbaceous plants. With such a varied group of plants, it is certainly important to distinguish between the different types so that you do not follow the wrong pruning guidelines. Within this one guide, it would be difficult to cover the hundreds of euphorbias that might be grown individually. Fortunately, many of the Euphorbia commonly grown in British gardens can be divided into three different groups for their pruning requirements. Prune Once Flowers Fade Timings will also very much depend on which euphorbia you are growing. However, with many Euphorbias, the time for pruning is either once the flowers fade or soon thereafter. With some types, the processes of pruning and deadheading are pretty much one and the same. So, while the details vary somewhat, the pruning of Euphorbias generally takes place in the late summer or autumn months. Pruning Evergreen Euphorbias Certain evergreen Euphorbias typically just need to be trimmed back immediately after flowering. This type of pruning pertains to: E. amygdaloides E. ‘Blackbird’ E. mellifera E. x pasteurii E. ‘Redwing’ Pruning in the case of these Euphorbias is simply deadheading and, other than removing the spent flowers and the upper portions of the flowering stems, no further cutting back or pruning is required. To cut back these Euphorbias, wait until the bracts surrounding the flowers turn completely brown, then remove the tops of the flowering stems, cutting back to the first ring of leaves below. Pruning Euphorbias With Biennial Stems Some types of Euphorbia produce biennial stems. In other words, they have two different types of shoots: those that grew the previous season on which flowers will form and those that grew during the present growing season. These types include: E. characias E. x martini E. myrsinites E. rigida The idea is that you should cut down the growth of the previous season, on which the flowers form. Cut these back to the ground in the late summer or autumn but leave the present season’s growth in place, as this will flower next year. Pruning Herbaceous Perennial Types When it comes to the herbaceous perennial Euphorbias, flowers are deadheaded once they fade. The euphorbias include: E. cyparissias E. epithymoides E. griffithii E. palustris E. sikkimensis E. villosa E. wallichii The whole of the plant is then cut to the ground later. You can cut back the entire plant to ground level before the first frosts or let the dead stems stand over the winter months to benefit wildlife, before cutting back early in the spring before new growth begins to emerge. “When pruning Euphorbia, long sleeve tops, gloves and washing your hands afterwards are recommended as the sap is phototoxic (activated by sunlight),” shares Master Horticulturist Dan Ori. These simple tips above should help you make sure that you prune, cut back or deadhead your Euphorbias correctly and do not do any harm to your plants.
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Highlighting 14 Excellent Euphorbia Varieties From This Diverse Group Of Plants
IN THIS GUIDE 1) E. amygdaloides var. robbiae 2) E. characias 3) E. cornigera 4) E. griffithii 5) E. hypericifolia 6) E. ingens 7) E. lathyris 8) E. mellifera 9) E. milii 10) E. myrsinites 11) E. oblongata 12) E. palustris 13) E. schillingii 14) E. sikkimensis Euphorbias are generally divided into those that are suitable for outdoor cultivation in the UK and those that are commonly grown as houseplants or in greenhouses in our climate. These are very varied plants, and though they share a genus, they can differ greatly in their appearance, growth habits and needs. One of the first things that you will have to decide when choosing a Euphorbia to grow is where you will be growing it. E. milii Even among Euphorbias that can be grown outside, there are many differences in the environmental conditions that different species and cultivars within this genus prefer. Some do best in full sun and free-draining conditions, while others will do best in consistently moist soil positioned in partial shade. Another important thing to think about is the size to which a particular species and cultivar of Euphorbia will grow, as they can differ greatly in this respect too. Some are larger herbaceous perennials or shrubs, whilst some are low-growing ground cover plants. E. obesa “A great Euphorbia to try is Euphorbia obesa,” says Darren Evans from Pugh’s Cacti. “It grows slowly and produces a dome shape that flowers along its ribs. E. eritrea “Euphorbia eritrea is another variety to try. It grows fast and can reach 15 feet in height, as it does in our nursery.” Linked with the size of a Euphorbia are its growth habits and the general details of its appearance. In these respects too Euphorbia can be an incredibly diverse group. E. epithymoides With all that said, here are some of my favourite varied euphorbias that might be considered by gardeners in the UK. 1) E. amygdaloides var. robbiae COMMON NAME(S): Mrs Robb’s bonnet HARDINESS RATING: H6 FOLIAGE: evergreen FLOWERING SEASON(S): spring / summer SUNLIGHT: any SOIL REQUIREMENTS: loam, sand, clay; any pH SIZE: 0.1-0.5m in height, 1-1.5m spread Also known as Mrs Robb’s Bonnet, this Euphorbia is a perennial evergreen that grows to around 50cm tall. It forms rosettes of deep green leaves and bears large, rounded sprays of yellowy-green flowers in the spring and summer. “We always use plants like E. amygdaloides var. robbiae that are great for filling in spots under trees,” shares Garden Designer Tom Simpson. This is a good choice for areas of dry shade, though it can also grow in partial shade or full sun. It will do best in moist but well-drained or well-drained soil. 2) E. characias COMMON NAME(S): Mediterranean spurge HARDINESS RATING: H4 FOLIAGE: evergreen FLOWERING SEASON(S): winter / spring SUNLIGHT: full sun SOIL REQUIREMENTS: loam, sand, clay; any pH SIZE: 1-1.5m in height, 1-1.5m spread Mediterranean spurge is a great plant for pollinators. It is a perennial that is evergreen and grows to around 1.5m tall. It has biennial stems, which are leafy in their first year and flowers in their second, becoming bare over the lower part of the stem. The flowers are prolific, borne in the spring in large cylindrical heads made up of petal-like bracts around tiny bright yellowy-green flowers. This is a short-lived perennial that often self-seeds when placed in the right location. Grow in well-drained soil in full sun in a sheltered spot. 3) E. cornigera COMMON NAME(S): horned spurge HARDINESS RATING: H5 FOLIAGE: deciduous FLOWERING SEASON(S): summer SUNLIGHT: full sun / part shade SOIL REQUIREMENTS: loam, sand, clay; any pH SIZE: 0.5-1m in height, 0.5-1m spread Horned spurge has an RHS Award of Garden Merit and is another good choice for a pollinator-friendly garden. This is a spreading perennial which grows around 75cm tall. It has slightly reddish stems with dark green leaves and bears bright yellow flowers in the summer. This Euphorbia is best grown in full sun or part shade, in moist but well-drained soil. 4) E. griffithii COMMON NAME(S): Griffith’s spurge HARDINESS RATING: H7 FOLIAGE: deciduous FLOWERING SEASON(S): summer SUNLIGHT: part shade SOIL REQUIREMENTS: clay or loam; any pH SIZE: 0.5-1m in height, 0.5-1m spread Griffith’s spurge is a vigorous perennial with a spreading habit which can have a height and spread of up to 1m or so. It has lanceolate leaves which turn red and yellow in the autumn months and bears clusters of red, orange or yellow flowers at the beginning of summer. This is a Euphorbia that does best in part shade in moist yet free-draining soil. It will tend to do best in clay or loam soil, with an east or west-facing aspect. It is H7 hardy and is among the hardiest plants to grow, coping even in the coldest regions in extreme winter temperatures. “I find E. griffithii one of the best garden Euphorbias due to its hardiness and autumn colour,” shares Master Horticulturist Dan Ori. “I recommend planting it in a border with other plants that give red and yellow autumn colour like Acers and also try mixing in dark green-leaved evergreens with plants like Aucuba japonica ‘Rozannie’.” 5) E. hypericifolia HARDINESS RATING: H2 FOLIAGE: evergreen FLOWERING SEASON(S): spring / summer / autumn SUNLIGHT: full sun / part shade SOIL REQUIREMENTS: sand, loam, clay; any pH SIZE: 0.1-0.5m in height, 0.1-0.5m spread This is a tender Euphorbia that is best grown undercover indoors or in a greenhouse. It can also be placed outdoors in a mild, sheltered and sunny position with light, free-draining conditions. It is a good choice for hanging baskets or a container garden. This is a small evergreen perennial, with tiny dark green leaves and tiny white flowers which are borne from spring to autumn. However, this plant is only H2 hardy and won’t survive outdoors year-round. 6) E. ingens COMMON NAME(S): candelabra tree HARDINESS RATING: H2 FOLIAGE: evergreen FLOWERING SEASON(S): autumn / winter SUNLIGHT: full sun SOIL REQUIREMENTS: sand or clay; any pH SIZE: 12m in height, 8m spread Though it can grow to around 15m in height when fully grown, these cacti-like succulent plants are commonly much smaller and are commonly grown in containers. Ridged and with spines along their broad succulent stems, they can, when mature, produce greenish-yellow flowers followed by reddish or purple fruits. Requiring a free-draining and sheltered position in full sun, this Euphorbia is H2 hardy. It is usually grown as a houseplant indoors. “My E. ingens takes over a significant part of my greenhouse as the spines make it too hazardous for the house,” shares Dan. “It handles low temperatures well but does not like cold and damp conditions.” 7) E. lathyris COMMON NAME(S): caper spurge HARDINESS RATING: H5 FOLIAGE: evergreen FLOWERING SEASON(S): spring / summer SUNLIGHT: full sun / part shade SOIL REQUIREMENTS: chalk, sand, clay; any pH SIZE: 1-1.5m in height, 0.1-0.5m spread Also sometimes referred to as E. crucifolia and commonly known as caper spurge; this is an annual or biennial Euphorbia species. It will typically reach around 1.2m in height. Its leaves are around 15cm long and they extend directly sideways out of unbranched stems. In late spring and early summer, these plants have small yellow-green blooms that are followed by triple seed heads that turn brown as they mature. This Euphorbia likes moist but well-drained or well-drained soil in full sun or partial shade. 8) E. mellifera COMMON NAME(S): honey spurge HARDINESS RATING: H3 FOLIAGE: semi-evergreen FLOWERING SEASON(S): spring SUNLIGHT: full sun / part shade SOIL REQUIREMENTS: loam, sand, clay; any pH SIZE: 1.5-2m in height, 2-2.5m spread E. mellifera is another more tender Euphorbia that can be grown outdoors in some locations in summer but usually requires an indoors or undercover, frost-free spot in winter. It is a domed shrub with bright green lance-like leaves with paler veins down their centres and brownish flower heads which are borne in the late spring. This option requires well-drained soil in a sheltered location in full sun. It is H3 hardy so may be grown outdoors year-round only in the mildest, coastal locations in the south of the British Isles. 9) E. milii COMMON NAME(S): crown of thorns HARDINESS RATING: H1B FOLIAGE: evergreen FLOWERING SEASON(S): summer SUNLIGHT: full sun SOIL REQUIREMENTS: loam, sand, clay; any pH SIZE: 0.5-1m in height, 0.1-0.5m spread This Euphorbia, often also referred to as Crown of thorns, Christ plant, or Christ thorn, is a large evergreen plant with leathery oval leaves and clusters of small yellow flowers with vibrant bright red bracts. It requires well-drained conditions in full sun and is most commonly grown indoors or in a greenhouse year-round, though it may also be placed out into a sheltered position in a garden in summer. The hardiness rating for this Euphorbia is H1B. 10) E. myrsinites COMMON NAME(S): broad-leaved glaucous spurge HARDINESS RATING: H5 FOLIAGE: evergreen FLOWERING SEASON(S): spring SUNLIGHT: full sun SOIL REQUIREMENTS: all soil types; any pH SIZE: 0-0.1m in height, 0.1-0.5m spread Also known as broad-leafed glaucous spurge, this Euphorbia is an evergreen perennial which has trailing leafy stems with bright green leaves and, in spring, yellow-green flower clusters that are 10cm across. This ground cover plant grows only around 10cm tall but can spread over 40-50cm wide. Grow this plant in full sun in well-drained soil. It can cope with a sheltered or exposed location and is H5 hardy. 11) E. oblongata COMMON NAME(S): Balkan spurge HARDINESS RATING: H5 FOLIAGE: deciduous FLOWERING SEASON(S): spring / summer / autumn SUNLIGHT: part shade SOIL REQUIREMENTS: chalk or sand; any pH SIZE: 0.5-1m in height, 0.1-0.5m spread Balkan spurge is a clump-forming herbaceous plant with dark green stems, which turn red in autumn, and flat heads of yellow flowers that are 15cm wide and bloom over a long period between spring and autumn. This Euphorbia is best placed in a dappled shade somewhere it will receive sun for part of the day. Though it is perennial, it is most commonly grown as an annual and will readily self-seed in moist but well-drained, humus-rich soil where it is happy. So, you might see this plant popping up in your garden year after year. 12) E. palustris COMMON NAME(S): marsh spurge HARDINESS RATING: H7 FOLIAGE: deciduous FLOWERING SEASON(S): spring SUNLIGHT: full sun SOIL REQUIREMENTS: clay or loam; any pH SIZE: 0.5-1m in height, 0.5-1m spread E. palustris, also known as marsh spurge, is a herbaceous perennial which will grow up to around 90cm tall. It has vibrant mid-green leaves which often turn yellow or orange in autumn and bears terminal clusters of greenish-yellow blooms in the late spring. As the name suggests, this is an unusual Euphorbia in that it will do best not in free-draining conditions like so many of this genus, but instead will thrive in permanently moist soil. It will thrive in clay or loam in full sun and is H7 hardy. 13) E. schillingii COMMON NAME(S): Schilling spurge HARDINESS RATING: H5 FOLIAGE: deciduous FLOWERING SEASON(S): summer / autumn SUNLIGHT: part shade SOIL REQUIREMENTS: chalk or sand; any pH SIZE: 0.5-1m in height, 0.1-0.5m spread This is a herbaceous perennial with erect stems that hold green leaves with white veins down their middles and broad clusters of vivid yellow flowers in the summer and into autumn. These Euphorbias grow best in partial shade in moist but well-drained soil that is rich in organic matter. 14) E. sikkimensis COMMON NAME(S): Sikkim spurge HARDINESS RATING: H5 FOLIAGE: deciduous FLOWERING SEASON(S): summer SUNLIGHT: full sun / part shade SOIL REQUIREMENTS: all soil types; any pH SIZE: 1-1.5m in height, 0.5-1m spread Sikkim spurge is an upright herbaceous perennial which has narrow leaves on stems that are a pinkish colour when young. The flowers, borne in loose heads in late summer, are bright yellow in hue. It needs moist but well-drained soil and is H5 hardy. There are, of course, many more species besides those listed above and there are also many cultivars of different species to contend with when making your choice. The above just serves to show how much variety there is in this genus, how many Euphorbias there are to choose from and just how different they can be.
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