Growing
Cut Back Rudbeckia In Early Spring And Deadhead Throughout Summer Say Experts
IN THIS GUIDE When To Prune 1) Clean Your Tools 2) Cut Back During Early Spring 3) Deadhead Throughout The Blooming Season Also known as black-eyed or brown-eyed Susans, Rudbeckias are cheerful plants with a lengthy blooming season and decent resilience to the British climate. Having said that, they will benefit from regular pruning in order to extend their blossoms for as long as possible – as well as to keep them from propagating all over the place. Although not strictly necessary, pruning will certainly enhance the aesthetic appeal and practical qualities of your plant, while cutting it back will promote new growth the next year. To do so, follow these steps: Clean and/or sharpen your cutting tools Cut back well during early spring Deadhead finished flowers throughout the blooming season If you’d like more of a detailed guide on any of those specific steps, just keep reading! Difficulty Easy Equipment Required Gardening gloves, pruning shears, cloth, isopropyl alcohol, mulch When To Prune Spring and summer When To Prune You can cut back your rudbeckia plants any time after they have finished blooming, though waiting until springtime is preferable. That’s because the spent flowers will provide vital nutrition in the shape of seeds for birds throughout autumn and winter, while fallen growth will insulate their roots over the colder months. In June, July and August, it is advisable to keep your pruning shears at the ready and deadhead any spent blossoms as soon as they appear. This will prevent seed production, which propagates the plant and diverts energy away from blossoming. “Rudbeckias are popular in naturalistic plantings because of their associability with grasses and other perennials,” shares Colin Skelly, a Horticultural Consultant. “This style of planting doesn’t require deadheading, as the spent blooms are part of the aesthetic and allow self-sowing. “If you are deadheading, remember that the more you remove, the less seed there will be for the birds.” 1) Clean Your Tools One step that is often overlooked in plant care of all types is maintaining your tools. Blunt shears can damage a plant’s stems and stunt its growth, while dirty blades can spread diseases. As such, be sure to keep the blades of your pruning shears as sharp as possible, replacing them every few years if necessary. Clean them before use and also afterwards, by soaking a clean rag in isopropyl alcohol, making sure to wipe the blades firmly to remove all impurities. Wear gardening gloves throughout this process. 2) Cut Back During Early Spring As mentioned above, you can cut back your rudbeckia plant earlier than spring, though if you do remove fallen growth, be sure to replace it with 2-3 inches of mulch to insulate the roots. Leaving the spent blooms in place is a good idea to feed your local bird population. When the time comes, cut the entire plant back to just above the soil level, making sure to cut at a 45° angle to prevent moisture build-up from rainwater. Rake away any fallen growth and replace it with a fresh layer of mulch. 3) Deadhead Throughout The Blooming Season If you want to maintain beautiful blooms for as long as possible, you need to make sure that your rudbeckia does not become distracted by seed production during the summer months. That means keeping an eye out for spent blossoms and tackling them as soon as they appear. When deadheading, you can prune stems with just a single spent blossom all the way back to where they join the main stem. For those with multiple blossoms (not all of which are spent), simply remove the offending flowerhead. Repeat as necessary.
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Collect Seeds From Spent Rudbeckia Flowerheads And Sow Indoors For Next Season
IN THIS GUIDE When To Sow Rudbeckia 1) Sow The Seeds 2) Separate Out Into Pots 3) Harden Off 4) Transplant Outdoors 5) Rudbeckia Aftercare With their large, daisy-like flowerheads, bright colours and extended flowering season, it’s no surprise that rudbeckias are popular across the UK. The fact that they’re fairly hardy, depending on the exact species, is another bonus in a country where the climate doesn’t always play nice. You might wish to create some insurance, however, by collecting seeds from spent flowerheads and sowing them indoors for the following season – or simply start a new collection by buying store seeds. Either way, you should follow the same process, outlined below: Sow the seeds in a seed tray with a suitable growing medium. Separate your seedlings out into individual pots. Harden off your rudbeckia in a colder environment. Transplant outdoors from May onwards. Care for your plants well to encourage autumn flowering. We understand that those steps might seem a little daunting to those with little experience in the horticultural world, which is why we’ve covered them in greater detail below. Difficulty Easy Equipment Required Seed tray, individual pots, potting soil, trowel When To Sow February-April When To Plant Out May-September When To Sow Rudbeckia While it is theoretically possible to directly sow rudbeckia seeds into your garden, the inclemency of the British climate makes it inadvisable. Instead, sow them in a seed tray inside your greenhouse or home to allow for easy germination, before separating them into individual pots and finally transplanting them outside. Sow the seeds initially in springtime, separating them out after 2-3 weeks. Do not transplant outdoors until all danger of frost has passed. 1) Sow The Seeds Prepare the seeds by placing them inside a damp cloth or paper towel for a few hours to fully hydrate them prior to sowing. You can also submerge them in a glass of water, but take care to ensure they do not drown. “Seeds might not look alive, but they are slowly respiring,” shares Master Horticulturist Colin Skelly. “Whilst submerging them in water might allow them to imbibe water to start the germination process, this should only be brief so that they can continue to breathe.” Then, using a good quality compost or potting soil that’s free from peat, sow your seeds in a seed tray at a minimal depth, since light is necessary for the germination process. Keep them moist and warm. 2) Separate Out Into Pots Once the seedlings have produced growth and are large enough to handle, it’s time to separate them into individual pots so that they can fully establish themselves. Take care when separating them to ensure their roots do not become damaged. Use pots with a diameter of between 7.5-10cm and plant the seedlings so that their shoots are level with the top of the pot. Water thoroughly and keep in a warm, dry place initially. 3) Harden Off After a couple of days of getting used to their new environment, it’s time to begin preparing your rudbeckia for the colder temperatures they will experience outdoors. You can do this by removing them to a colder room or opening the window for several hours a day. The process should be a gradual one to avoid giving the rudbeckia too great a shock to the system, which could result in early death. Overall, expect the hardening process to take around 2 weeks, though longer is fine if need be. 4) Transplant Outdoors Once the final frost of the year has passed and your seedling has begun to produce healthy foliage, it’s time to move them to their final position outdoors. Choose a fertile, well-draining spot which enjoys lots of organic matter and good sunshine. Plant your rudbeckias at least 30cm apart, but arrange them in drifts or alongside complementary flowers such as asters, echinacea or a variety of grasses for an aesthetically pleasing effect. 5) Rudbeckia Aftercare Once your rudbeckia plant has become fully established outdoors, it doesn’t require pinching and can fend for itself for the most part. However, you should take care to keep it hydrated during particularly dry spells, always watering the soil rather than the foliage and flowers. Apply liquid plant food every 2 weeks. Deadhead throughout the blooming season to prolong it and prevent unwanted propagation. Leave the final round of spent flowers on the plant in autumn to provide food for birds throughout the winter, then cut back in spring. Remove all fallen foliage and replace it with 2-3 inches of fresh mulch.
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Boost Your Rudbeckia Flowers By Dividing Their Ever-Spreading Root System
IN THIS GUIDE When To Divide 1) Prepare The Plant 2) Remove Your Plant From The Ground 3) Divide Into Sections 4) Transplant Your Divided Plants Rudbeckias are cheerful daisy-like plants that add charm and joy to any garden. They have an ever-spreading root system that forms clumps of thin roots. Over time the roots can become tangled and matted which will reduce flowering - dividing your rudbeckias every few years will prevent this. It can also give you new little plants to put in your garden or share with family and friends. Here’s how to do it: Prepare the plant with some watering and loosening of the soil. Remove the plant from the ground with a shovel or spade. Divide the plant at the roots to create several new sections. Transplant the divided plants into your preferred locations. Difficulty Easy Equipment Required Gloves, shovel or similar tool When To Divide Early spring When To Divide The best time to divide your rudbeckias is in early spring when you start to see new growth. We also recommend dividing your rudbeckias on a cloudy day to prevent your plants from drying out. 1) Prepare The Plant You will want to give your plants a generous glug of water the day before you plan to divide them. You should also prepare the spot where you wish to plant your new divisions. Loosen the soil and remove any weeds, stones and leftover plant material. Trim back the foliage of your rudbeckia to make division easier. 2) Remove Your Plant From The Ground Using a sharp shovel or similar, dig into the ground about 15cm from the leaf edges around the circumference of your plant. Gently remove the plant from the ground in one clump if possible. If it’s particularly overgrown, cut it apart with secateurs and remove the plant section by section. 3) Divide Into Sections Shake the rootball to remove as much soil as possible, or use a hose to gently spray water over the roots. Now you can separate the plant into sections. Make sure each one has 3-5 young healthy-looking shoots. Pull the sections apart either with your hands, or cut them with a sterilised blade. “A great tool for this sort of task is a hori hori, a Japanese knife-like tool that is perfect for slicing or fine weeding,” shares Master Horticulturist Colin Skelly. “They are increasingly popular due to their versatility and are becoming widely available in the UK.” 4) Transplant Your Divided Plants Once you have separated your rudbeckia, you should plant them into their new home immediately to prevent the roots from drying out. Dig a hole and place the rudbeckia at a similar depth to the depth you removed it from. Cover with soil and pat the surface of the soil into place, then water your plants thoroughly.
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10 Rudbeckia Varieties Including Compact, Space-Filling And Colourful Options
IN THIS GUIDE 1) R. hirta ‘Indian Summer’ 2) R. fulgida ‘Little Goldstar’ 3) R. hirta ‘Cherokee Sunset’ 4) R. hirta ‘Toto’ 5) R. hirta ‘Irish Eyes’ 6) R. hirta ‘Prairie Sun’ 7) R. hirta ‘Cherry Brandy’ 8) R. laciniata ‘Herbstsonne’ 9) R. fulgida var. sullivantii ‘Goldsturm’ 10) R. ‘Aries’ A favourite throughout the British gardening scene, rudbeckias offer a plethora of advantages to horticulturalists both amateur and commercial. They’re easy to cultivate, produce infectiously cheerful flowerheads and their blooming season extends well into autumn. What’s more, they’re also available in a range of different styles and sizes, with cultivars reaching between 0.5-2m in height and spanning a spectrum of different shades of yellow. R. ‘Golden Glow’ There are a number of different rudbeckia varieties too, including R. hirta, R. fulgida and R. laciniata. When selecting a species for your outdoor display, it’s important to consider the space available to you, the other plants already in situ and the overall effect you’re trying to create. Here’s a list of some of our favourites to give you some inspiration. All varieties in this list can be grown in full sun or part shade and in an exposed or sheltered location. 1) R. hirta ‘Indian Summer’ COMMON NAME(S): black-eyed Susan ‘Indian Summer’ HARDINESS RATING: H3 FLOWERS: Yellow and purple FLOWERING SEASON(S): Summer / Autumn SOIL PREFERENCE: Clay or loam; Any soil pH SIZE: 0.5-1m in height, 0.1-0.5m spread Perhaps the classic example that most people think of when they hear the word rudbeckia, ‘Indian Summer’ boasts bright yellow petals clustered around a dark brown stigma, typical of the R. hirta variety from which it hails. The plant is capable of growing up to 90cm in height and will self-seed freely if allowed to do so unchecked, making for effortless propagation. However, you should be careful to thin out seedlings to allow adequate space between them so as to improve air circulation and prevent the development of mildew. 2) R. fulgida ‘Little Goldstar’ COMMON NAME(S): black-eyed Susan ‘Little Goldstar’ HARDINESS RATING: H6 FLOWERS: Yellow, gold and brown FLOWERING SEASON(S): Summer / Autumn SOIL PREFERENCE: Clay, sand, loam; Any soil pH SIZE: 0.1-0.5m in height, 0.1-0.5m spread Something akin to a miniature ‘Indian Summer’, ‘Little Goldstar’ reaches just 50cm in height, making it one of the most compact rudbeckia varieties available. “Rudbeckia ‘Little Goldstar’ is a great compact option where you don’t have the space to create the archetypal herbaceous border with short, mid and tall plants running front to back (although it could play the role of front of border very well),” shares Colin Skelly, a Master Horticulturist. That means it’s a perfect choice for gardens where space is at a premium and it’ll do a great job in filling space in beds and borders. With slightly thinner petals and a more purplish hue to its centre than its larger counterpart, ‘Little Goldstar’ looks especially impressive when planted in drifts. Due to its smaller dimensions, it can also perform well in baskets, pots and other containers. 3) R. hirta ‘Cherokee Sunset’ COMMON NAME(S): black-eyed Susan ‘Cherokee Sunset’ HARDINESS RATING: H3 FLOWERS: Yellow, orange and gold FLOWERING SEASON(S): Summer / Autumn SOIL PREFERENCE: Clay or loam; Any soil pH SIZE: 0.5-1m in height, 0.1-0.5m spread One of the showstoppers of the rudbeckia world, ‘Cherokee Sunset’ boasts flowers in a variety of different colours, from burnished toffee to burnt copper to deep mahogany. Capable of reaching a height of up to 75cm, it’s a medium-sized rudbeckia which will bring in bees, butterflies and other pollinators by the bucketload. It can also come in single or double-flowering styles, making it an excellent choice as a cut flower. Indeed, there are those who say its ruffled flowerheads make it more reminiscent of a member of the dahlia family than their humbler coneflower counterparts. 4) R. hirta ‘Toto’ COMMON NAME(S): black-eyed Susan ‘Toto’ HARDINESS RATING: H3 FLOWERS: Yellow and purple FLOWERING SEASON(S): Summer / Autumn SOIL PREFERENCE: Clay or loam; Any soil pH SIZE: 0.1-0.5m in height, 0.1-0.5m spread At a maximum height of around 40cm, ‘Toto’ is one of the most diminutive rudbeckia species on offer. However, its 8cm-diameter flowerheads are somewhat oversized in proportion to its body and when planted in drifts, provide a delightful bobbing carpet of yellow and brown blooms. That’s because the flowers blossom so profusely during the summertime that they virtually obscure the lush green foliage below. Like other rudbeckias, you can encourage them to bloom for even longer by deadheading regularly. 5) R. hirta ‘Irish Eyes’ COMMON NAME(S): black-eyed Susan ‘Irish Eyes’ HARDINESS RATING: H3 FLOWERS: Yellow, gold and green FLOWERING SEASON(S): Summer / Autumn SOIL PREFERENCE: Clay or loam; Any soil pH SIZE: 0.5-1m in height, 0.1-0.5m spread Somewhat unusually for rudbeckias, ‘Irish Eyes’ is a black-eyed Susan without a black eye. Instead, it boasts a light green stigma at the centre of its flowerhead, which complements the buttery yellow petals surrounding it and serves as an unmissable beacon for any passing pollinators. It can reach up to 1m in height and will look best when planted alongside other plants that accentuate its finer features. For example, you could highlight the unusual green centres by planting them alongside ferns and foliage, or else next to green flowering plants. 6) R. hirta ‘Prairie Sun’ COMMON NAME(S): black-eyed Susan ‘Prairie Sun’ HARDINESS RATING: H3 FLOWERS: Yellow, gold and green FLOWERING SEASON(S): Summer SOIL PREFERENCE: Clay or loam; Any soil pH SIZE: 0.5-1m in height, 0.1-0.5m spread Like ‘Irish Eyes’, ‘Prairie Sun’ also forgoes the black centre of its flowerhead in favour of a light green alternative, although its stigma is more domed and less conical in structure. Nonetheless, it’s every bit as attractive to bees and birds, meaning it’s a great option for boosting biodiversity in your area. The other way in which ‘Prairie Sun’ differs from ‘Irish Eyes’ is the gorgeous variety of yellow in its petals. Starting out as a deep honey colour, they fade to a light lemon at the tips, making them a great addition to a cut display. 7) R. hirta ‘Cherry Brandy’ COMMON NAME(S): black-eyed Susan ‘Cherry Brandy’ HARDINESS RATING: H3 FLOWERS: Red and brown FLOWERING SEASON(S): Summer SOIL PREFERENCE: Clay or loam; Any soil pH SIZE: 0.5-1m in height, 0.1-0.5m spread If you grow tired of all the yellow blooms on your rudbeckia selection, it might be time to opt for something completely different in the shape of ‘Cherry Brandy’. As the name suggests, this exquisite specimen boasts flowerheads that are a mixture of burgundy and chocolate, making for an eye-catching end result. The dark tones of their blossoms look particularly attractive when paired with more traditional rudbeckia varieties, or even against the yellow-greenish tones of the two cultivars mentioned above. Grows to just 60cm in height. 8) R. laciniata ‘Herbstsonne’ COMMON NAME(S): coneflower ‘Herbstsonne’ HARDINESS RATING: H6 FLOWERS: Yellow FLOWERING SEASON(S): Summer / Autumn SOIL PREFERENCE: Clay, chalk, loam; Any soil pH SIZE: 1.5-2.5m in height, 0.5-1m spread This monster of a rudbeckia can reach up to 2m in height, meaning it’s a perfect choice for the back of a border or to spruce up a fence, wall or other border perimeters. The sturdy stems bear their flowerheads aloft, which are characterised by drooping yellow petals around a green stigma darkening to brown as it matures. ‘Herbstsonne’ is a late bloomer even among a genus that’s famed for its extended blooming season, meaning you can expect to see blossoms even into October. What’s more, its healthy mid-level foliage remains robust as long as the flowers do, meaning it’s still a sight to behold after all around it has faded. 9) R. fulgida var. sullivantii ‘Goldsturm’ COMMON NAME(S): coneflower ‘Goldsturm’ HARDINESS RATING: H6 FLOWERS: Yellow and brown FLOWERING SEASON(S): Summer / Autumn SOIL PREFERENCE: Clay, chalk, loam; Any soil pH SIZE: 0.5-1m in height, 0.1-0.5m spread Like ‘Indian Summer’ mentioned above, ‘Goldsturm’ is another of the rudbeckia varieties which inevitably spring to mind when hearing the name. However, it’s smaller than its relative, reaching just 60cm in height, while its petals are more elongated and separated, too. With these sword-like appendages shooting out from a bulbous brown centre, it’s a cultivar of the R. fulgida variety that has proven hugely popular around the country. 10) R. ‘Aries’ COMMON NAME(S): coneflower ‘Aries’ HARDINESS RATING: H3 FLOWERS: Yellow, brown and orange FLOWERING SEASON(S): Summer / Autumn SOIL PREFERENCE: Clay, sand, loam; Any soil pH SIZE: 0.5-1m in height, 0.1-0.5m spread ‘Aries’ cultivars boast semi-double blooms that are instantly recognisable by the reddish-brown staining around the central stigma, fading into a bright yellow at the outer tips of the petals. The yellow-tipped anthers on its dark brown stamen only complete the effect, making for one attractive rudbeckia. With a maximum height of 75cm, it’s a versatile option that will do just as well in a mixed border as it will in its own container. Especially popular among birds and bees.
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Rudbeckia Are Generally Problem Free - But There Are A Few Issues To Look Out For
IN THIS GUIDE 1) Rudbeckia Leaf Spot 2) Mildews 3) Pests Rudbeckias are well-loved by gardeners around the globe and have become a staple in the British country garden. Not only do gardeners love them but they are also beloved by helpful pollinators like butterflies and bees and are a source of food and shelter to many animals. Rudbeckias are particularly popular because they are so easy to grow and take care of. “Rudbeckias are the proverbial ‘bullet proof’ garden plant,” shares Horticultural Consultant Colin Skelly. “The only problem I have ever had with Rudbeckia is slugs and snails on young plants. Once established, they look after themselves and only need dividing every few years.” Like any plant though, there are a few problems you may run into. The most common issues gardeners experience when growing rudbeckia include: Rudbeckia leaf spot Mildews Pests See guidelines for dealing with each of these common problems below. 1) Rudbeckia Leaf Spot Rudbeckia can suffer from both bacterial and fungal leaf spot diseases. Bacterial Leaf Spot Bacterial leaf spot disease will usually present itself as red-brown or brown spots on the leaves which will sometimes have yellow borders around them. This type of disease can also cause the leaves to become malformed. Fungal Leaf Spot With fungal leaf spot diseases, you will often find tiny dark spots. You will see this disease start at the base of the plant and gradually work its way upwards. Preventing And Dealing With Leaf Spot As with any problem, ideally, we want to prevent it from happening in the first place. You can avoid leaf spot diseases by watering the plants at the base over the soil rather than watering them overhead. If you find you have a leaf spot disease in your rudbeckias, we advise removing and destroying the affected areas or the whole plant if the disease is widespread. Be sure to sterilise any equipment you use before and after to avoid the further spread of the disease. 2) Mildews Powdery and downy mildew are both common problems with Rudbeckias. Powdery Mildew Powdery mildew usually becomes a problem in summer. If you spot powdery white growth on the upper side of the leaves then powdery mildew is probably the culprit. Left untreated the leaves will become yellow and eventually drop off. If you notice powdery mildew on your plant you should remove and destroy the affected areas. Downy Mildew If you notice greyish-white, velvet-like growth on the underside of your leaves then you are probably dealing with downy mildew. You may also notice dark spots on the upper areas of the plant. Downy mildew can cause leaf drop and eventually kill the plant entirely. To prevent downy mildew do not use overhead watering but rather water directly over the soil at the base of the plant. 3) Pests Rudbeckias are usually untroubled by pests, however, aphids are quite partial to them. To get rid of aphids you could start by setting natural enemies on them that eat aphids. These can be bought at gardening centres or you can try and encourage them into your garden by planting their favourite plants. If this doesn’t work we advise using a low-strength insecticidal soap and apply liberally to the plant. As you can see rudbeckias are generally low-maintenance, making them perfect for novice gardeners!
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Crocosmia In Pots Will Require More Attention, But They Make Magnificent Displays
IN THIS GUIDE Choosing A Container Choosing A Compost Potting Up Container Care Crocosmia is an attractive flowering plant from South Africa which can enhance and brighten up your garden during the latter part of the growing season. Luckily, crocosmia can also be a great choice for container growing. You can grow any crocosmia variety in a pot, however, it is important to note that some are larger than others. So, if you are planting mixed displays, make sure that you choose a smaller cultivar to grow. Some crocosmias are very vigorous and can spread dramatically, and a more invasive type is often best grown in a container in order to prevent its spread. Crocosmias can look great in dedicated containers or in mixed container displays along with other late-bloomers like rudbeckia, penstemons, salvias, and ornamental grasses. Choosing A Container For a long-lasting display, it is best to choose a container of at least around 30-40cm across, so that you can plant several crocosmia corms or plants together. Crocosmia looks best when planted in larger clumps or drifts in a garden. Make sure that you choose a container which has adequate drainage at the base, and yet which will not lose moisture too quickly. Crocosmia needs a moist yet free-draining position, ideally in full sun, though these plants can also cope with some light shade. Choosing A Compost Crocosmia should do well in any peat-free, multipurpose potting compost, or a homemade blend. Just make sure that the compost or potting mix is moist yet free-draining, and that it contains plenty of organic matter for moisture retention and for fertility. A soil or loam-based compost is generally best for perennial plantings. Potting Up Compact crocosmia varieties can be potted up from containers in which they came as potted plants, or planted as dormant corms in spring. If you have purchased a potted plant, this can be potted up at any time of the year. It is best, however, to pot up when the conditions are not too hot and dry, as heat and drought can increase the chances of transplantation stress. “Crocosmia can make good container plants but ensure that you select shorter varieties and allow plenty of space for them to multiply,” says Mark Wash, Owner of Trecanna Nursery. The best time to pot up crocosmias and other perennials is in early spring, so they stand the best chance of becoming well-established before the flowering period and the following winter. How Many Can You Plant Per Pot? If planting corms, these should be planted at a depth of around 3 times their height, space in small groups, 10-20cm apart to ensure a fast maturing and attractive display. If planting potted plants, how many you can plant per pot will depend on the size of the specimen you have chosen, and the variety. Make sure that you understand the eventual height and spread which is to be expected for the cultivar you have chosen, and give it room to grow. Remember that these are plants which will spread out, forming larger clumps each year. Crocosmia can later be divided so you can fit them in fairly snugly into the pot you have chosen, as long as there is some growing medium around each one for the plants to grow into. Remember, this plant looks wonderful in mixed container displays. “I like to grow Crocosmia alongside Dahlias in large pots as I find that the foliage and flower stem compliment each other,” says Colin Skelly, a Master Horticulturist. “Crocosmia × crocosmiiflora becomes too vigorous a spreader and has become a problematic garden escapee into surrounding landscapes. “However, most cultivars are far less likely to present overly vigorous spreading. Growing is a great way to make sure.” When choosing other plants to place alongside them, look at the size of the root system of each of those plants and take care not to overcrowd the space. Container Care “When growing in containers, crocosmia will require more attention to watering and will need to be divided more often, maybe every two years,” explains Mark. Water crocosmias that are growing in pots well throughout the growing season and check regularly to make sure that the growing medium does not dry out. Feed with a potash-rich feed every couple of months through the growing season. Replenish an organic mulch over the top of the container each spring for moisture retention and fertility. Cut down dead foliage to the base in early spring. Though usually hardy, make sure crocosmias in pots are not placed in an overly cold or exposed location for the winter months. Consider insulating the pots to protect the corms in particularly cold areas. Lift and divide congested clumps every 3-5 years to keep the display flowering well.
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Most Crocosmia Corms Should Survive Winter - Follow These Steps To Be Sure
IN THIS GUIDE What Happens To Crocosmia In Winter? 1) Cut Back Dead Foliage 2) Mulch Your Corms 3) Insulate Potted Crocosmia Crocosmias are hardy plants which can generally cope well with UK winter conditions. As herbaceous perennials, their foliage will die back over the winter months before the plants burst into new growth in the spring. Crocosmias vary slightly in hardiness depending on the variety that you have chosen to grow. Some are H5 hardy, which means that the corms will survive the winter across the UK, even during extreme winters. Some are H4, and while they will usually be hardy, damage may occur to the corms during extreme conditions or in the coldest parts of the British Isles. To care for crocosmia in winter: Wait for foliage to die back naturally at the end of autumn or early winter and then cut back foliage any time after die back, ideally in early spring. Mulch crocosmias in the ground with an insulating layer of compost or other organic material. Consider insulating pots to protect corms in containers in colder locations. Read on to learn a little more about the above, and to make sure that your crocosmia corms make it through the winter months unscathed: What Happens To Crocosmia In Winter? As colder weather arrives, and winter approaches, the foliage which, after flowering, has continued to photosynthesise and collect energy which is stored in the corms below the ground over the winter, will begin to die back naturally. The green leaves will turn brown and begin to dry up and the energy gathered by the leaves will be stored in the corms, which will remain dormant over the winter months. Winter care is all about making sure that the corms are safe, and won’t be damaged, as damaged corms may result in poor growth and flowering the following year. Here are the steps you need to follow to overwinter your crocosmia successfully. 1) Cut Back Dead Foliage Any time after the leaves have died back naturally, you can cut back the dead foliage to the ground. As long as the leaves are brown, cutting back should not cause any problems, but make sure that you do not cut back green foliage, as cutting back too early can cause issues with flowering and growth next year. However, while you can cut back in winter, it is usually best to leave the dead foliage in place over the coldest months. For one thing, the dead foliage makes a great habitat, providing shelter for garden wildlife during the coldest part of the year. For another, the dead foliage will also help a little in providing protection to the corms below the ground. However, if you prefer to keep things neat and tidy in your winter garden, or if there has been a problem with disease, you can cut back and remove the material as soon as winter arrives. “I suggest that you cut crocosmia back late in the year, leaving around 30cm which will protect young growth in early spring,” recommends Mark Wash from Trecanna Nursery. Remember, crocosmia cuttings can be added to your composting system, as long there is no disease. If there is an issue, you should dispose of the material so that the problem does not spread. 2) Mulch Your Corms Even though crocosmias are hardy plants, it can be a good idea to add an insurance policy and make sure the corms in the ground remain safe from winter cold by replenishing the mulch above the corms before winter arrives, as Master Horticulturist Colin Skelly: “Crocosmia will struggle to thrive in very dry or very wet soils. “If these are an issue, then an annual mulch will also help to alleviate these soil conditions as well as provide winter insulation.” A thick layer of homemade compost or other organic material will help keep the corms protected if it is very cold. “A good bark mulch will protect the corms over winter and help cap-in moisture in the soil for next year,” says Mark. 3) Insulate Potted Crocosmia If you are growing crocosmia in containers, it is a good idea to think about insulating pots – especially if you live in a colder area. Corms in pots are more exposed to winter cold than those growing in the ground. You can wrap fleece, bubble wrap or other materials around the pot as an insulating layer. You might also move container-grown plants to a less exposed location in colder regions. You should also make sure that waterlogging does not become an issue. Ensure that drainage holes are draining freely and during wet spells over winter, consider raising pots up off the ground. As you can see from the above, crocosmias are easy to care for and won’t require much work, during the winter. They are just as easy to care for in winter as they are during other seasons of the year.
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15 Knockout Crocosmia Varieties With Advice From An Experienced Grower
IN THIS GUIDE 1) C. × crocosmiiflora ‘Babylon’ 2) C. × crocosmiiflora ‘Citronella’ 3) C. × crocosmiiflora ‘Coleton Fishacre’ 4) C. × crocosmiiflora ‘Emily McKenzie’ 5) C. × crocosmiiflora ‘George Davidson’ 6) C. × crocosmiiflora ‘Harvest Sun’ 7) C. ‘Hellfire’ 8) C. × crocosmiiflora ‘Honey Angels’ 9) C. ‘Lucifer’ 10) C. masoniorum 11) C. ‘Paul’s Best Yellow’ 12) C. × crocosmiiflora ‘Saracen’ 13) C. ‘Severn Sunrise’ 14) C. ‘Spitfire’ 15) C. × crocosmiiflora ‘Star of the East’ References Crocosmias are beautiful flowering perennials that come in a range of different sizes and lots of warm, fiery hues. When choosing a crocosmia to grow, it is important to note that some spread far more widely and quickly than others. C. × crocosmiiflora can actually become invasive, both in the garden and in the surrounding countryside.1 Some are shorter and more compact, others far taller. It is important to choose the right variety for your needs and also to prevent the spread of more invasive types into the surrounding environment, where they can become a problem for local plant life. It is also important to consider the hues of the flowers, and how the particular cultivar will long alongside the other plants you are growing in your garden. Mark Wash, the owner of Trecanna Nursery, shared his thoughts on the varieties of crocosmia: “What a difficult question to answer!” Mark said after being asked to choose a favourite. “If it’s an orange flower you’re after, I’d go for ‘Columbus’ with its purple buds followed by apricot flowers. C. x crocosmiiflora ‘Columbus’ “For yellow flowers ‘Lemon Spray’ is a beautiful primrose-yellow and for red, maybe our own ‘Tamar Double Red’, which was recently awarded an RHS Award of Garden Merit. “All three of these varieties are really beautiful plants, producing a reliable display year after year.” With Mark’s choices in mind, I’ve put together my own list of 15 varieties. Here are some of the best and most interesting crocosmias to consider growing in your garden. All of the varieties in this list can be grown in any moist but well-drained soil with any pH, and can be positioned in either full sun or partial shade, in an exposed or sheltered location. 1) C. × crocosmiiflora ‘Babylon’ COMMON NAME(S): montbretia ‘Babylon’ HARDINESS RATING: H4 FLOWERS: Red and yellow FLOWERING SEASON(S): Summer SIZE: 0.5-1m in height, 0.1-0.5m spread This crocosmia grows to an eventual height of around 1m, with a spread of 0.1-0.5m. It has large, orangey-red flowers, with a golden yellow inside, surrounded by a dark ring. This option is H4 hardy and is a recipient of the RHS AGM. 2) C. × crocosmiiflora ‘Citronella’ COMMON NAME(S): Crocosmia citronella HARDINESS RATING: H5 FLOWERS: Yellow FLOWERING SEASON(S): Summer / Autumn SIZE: 0.5-1m in height, 0.1-0.5m spread This fresh and zesty choice has upright light green leaves and small soft yellow flowers. It has an eventual maximum height and spread of around 60cm. The lively yellow flowers look great alongside more orange or red crocosmia and also with other late summer or autumn flowers, like Rudbeckia ‘Herbstsonne’, or Canna ‘Semaphore’. 3) C. × crocosmiiflora ‘Coleton Fishacre’ COMMON NAME(S): montbretia ‘Coleton Fishacre’ HARDINESS RATING: H5 FLOWERS: Yellow FLOWERING SEASON(S): Summer SIZE: 0.5-1m in height, 0.1-0.5m spread This is another yellow flowering crocosmia, but this one has flowers with a richer, more golden yellow hue. The plants grow to around 60cm tall, with a spread of 0.1-0.5m. This option is H5 hardy and is a good choice for a partially shaded spot. 4) C. × crocosmiiflora ‘Emily McKenzie’ COMMON NAME(S): montbretia ‘Emily McKenzie’ HARDINESS RATING: H4 FLOWERS: Red and orange FLOWERING SEASON(S): Summer SIZE: 0.5-1m in height, 0.1-0.5m spread A great choice for container growing or small spaces, this is one of the more compact crocosmia. It grows to around 60cm in height but will spread to only around 8cm, forming small, dense clumps. The blooms are bright orange, with a mahogany hue in the throat. Try growing this alongside Achillea ‘Terracotta’, or Echinacea ‘Irresistible’ for beautiful late summer and early autumn displays. 5) C. × crocosmiiflora ‘George Davidson’ COMMON NAME(S): montbretia ‘George Davison’ HARDINESS RATING: H5 FLOWERS: Yellow FLOWERING SEASON(S): Summer SIZE: 0.5-1m in height, 0.1-0.5m spread This is another yellow crocosmia which has golden yellow flowers, like those of freesias, which bloom well into autumn. This grows to around 60cm in height and spread, holding its own alongside other dramatic flowering plants like kniphofia (Red Hot Pokers) or ornamental grasses. 6) C. × crocosmiiflora ‘Harvest Sun’ COMMON NAME(S): montbretia ‘harvest sun’ HARDINESS RATING: H5 FLOWERS: Red and yellow FLOWERING SEASON(S): Summer SIZE: 0.5-1m in height, 0.1-0.5m spread This is a fairly new crocosmia hybrid, which has upright form, fresh green foliage, and large red-orange flowers that are great for a tropical planting scheme with exotic-looking dahlias. It grows around 90cm tall with a spread of around 45cm. 7) C. ‘Hellfire’ COMMON NAME(S): montbretia ‘Hellfire’ HARDINESS RATING: H5 FLOWERS: Red FLOWERING SEASON(S): Summer SIZE: 1-1.5m in height, 0.1-0.5m spread This is another taller crocosmia, with bright red flowers on arching stems which can reach a height of around 1m, or even a little more. The plant has a spread of around 0.1-0.5m. It is H5 hardy and can be grown in full sun or partial shade. The petals of these flowers open up more than those on many other cultivars and are large and dramatic. A recipient of the RHS Award of Garden Merit. 8) C. × crocosmiiflora ‘Honey Angels’ COMMON NAME(S): montbretia ‘Honey Angels’ HARDINESS RATING: H5 FLOWERS: Yellow FLOWERING SEASON(S): Summer SIZE: 0.5-1m in height, 0.1-0.5m spread This RHS recipient is a charming and somewhat more delicate variety – it has creamy yellow flowers. It grows to a height of around 75cm and has a spread of 0.1 to 0.5m and is H5 hardy. This cultivar looks great in gentle prairie planting schemes alongside grasses and other late-flowering perennials, like salvias. 9) C. ‘Lucifer’ COMMON NAME(S): montbretia ‘Lucifer’ HARDINESS RATING: H5 FLOWERS: Red and orange FLOWERING SEASON(S): Summer SIZE: 1-1.5m in height, 0.1-0.5m spread A famed crocosmia cultivar, ‘Lucifer’ is a UK garden favourite with vibrant red flowers. It grows up to 1.2m in height with an eventual spread of less than 0.5m. This is one of the earlier crocomia to flower, doing so from around July, and it is great for the back of a border. “C. ‘Lucifer’ might be an older cultivar, but it is tried and tested and, to my mind, not bettered, particularly for early flowering,” shares Master Horticulturist Colin Skelly. “The length and arch of its flowering stems makes it a real eye-catcher.” It is well known for its vigour and resilience. 10) C. masoniorum COMMON NAME(S): giant montbretia HARDINESS RATING: H4 FLOWERS: Red and orange FLOWERING SEASON(S): Summer SIZE: 1-1.5m in height, 0.1-0.5m spread Also known as giant crocosmia, this is another great taller plant for the back of a border. It has bright orange-red, upward-facing flowers, born on stems which can reach around 1.2m in height. It has a spread of 0.1-0.5m and is H4 hardy. This plant has received the RHS Award of Garden Merit. “I really like C. masoniorum for its height and drama in late summer, although I find that it needs dividing every three years or so to keep it where I want it!” adds Colin. 11) C. ‘Paul’s Best Yellow’ COMMON NAME(S): montbretia ‘Paul’s Best Yellow’ HARDINESS RATING: H4 FLOWERS: Yellow FLOWERING SEASON(S): Summer / Autumn SIZE: 1-1.5m in height, 0.5-1m spread The beautiful bright golden yellow flowers of this cultivar are borne on stems that can tower to 1.5m, with a spread of up to 1m or so. The tall flowering stems can make this a great choice for larger gardens and the flowers are great for cutting for household displays. 12) C. × crocosmiiflora ‘Saracen’ COMMON NAME(S): montbretia ‘Saracen’ HARDINESS RATING: H4 FLOWERS: Red, orange and yellow FLOWERING SEASON(S): Summer SIZE: 0.5-1m in height, 0.1-0.5m spread The thin strap leaves of this cultivar are a mid-green tone, flushed with a bronze hue. The flowers are bright reddish-orange, with yellowish throats. They are borne in mid to late summer on stems which grow to around 75cm high. It is H4 hardy and spreads to 0.1-0.5m. 13) C. ‘Severn Sunrise’ COMMON NAME(S): montbretia ‘Severn Sunrise’ HARDINESS RATING: H5 FLOWERS: Orange and pink FLOWERING SEASON(S): Summer SIZE: 0.5-1m in height, 0.1-0.5m spread The beautiful flowers on this plant start out a vibrant orange and fade to a pinker hue, giving the effect of a sunrise with their warm colouration. They can bring a tropical and exotic flair to your garden and look great alongside vibrant daylilies, dahlias and gazanias. This cultivar has a height of 0.5-1m and a spread of 0.1-0.5m. It is H5 hardy and best in partial shade. 14) C. ‘Spitfire’ COMMON NAME(S): montbretia ‘Spitfire’ HARDINESS RATING: H4 FLOWERS: Red and orange FLOWERING SEASON(S): Summer SIZE: 0.5-1m in height, 0.1-0.5m spread Reaching 0.6-1m in height and bearing vibrant reddish-orange flowers in the later half of summer, this cultivar is a fairly compact crocosmia with a well-behaved dwarfing growth habit, which is easy to keep in check in your garden. This, along with the better-known ‘Lucifer’, was introduced in 1966 and has been gracing UK gardens for many years.2 15) C. × crocosmiiflora ‘Star of the East’ COMMON NAME(S): montbretia ‘Star of the East’ HARDINESS RATING: H4 FLOWERS: Orange FLOWERING SEASON(S): Summer / Autumn SIZE: 0.5-1m in height, 0.1-0.5m spread This cultivar has light orange flowers with paler yellow centres, which can grow to around 10cm across. These are born on stems around 0.5-1m high in late summer. This is a H4 hardy cultivar which can grow well in full sun or partial shade. While the options on this list are amongst the most highly regarded crocosmia that you can grow here in the UK, there are, of course, plenty of other options to consider. By looking at size, growth habit, colour and size, you can choose an option which might work best in your own particular garden. References 1. Crocosmia x crocosmiiflora (montbretia). (2022, January 7). CABI Compendium. https://doi.org/10.1079/cabicompendium.55282 2. Plant Stories. (2020, August 15). Essex Gardens Trust. Retrieved March 14, 2023, from https://www.essexgardenstrust.org.uk/plant-stories
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Tree Peonies Look Phenomenal At The Rear Of A Border: This Is How You Can Grow Them
IN THIS GUIDE Overview Tree Peony Vs Peony – What’s The Difference? Common Varieties How To Grow Tree Peonies Tree Peony Care References Tree peonies are not actually trees at all; they are shrubs, with pleasing foliage and dramatic blooms. These plants look lovely at the back of a border, but is this plant the right choice for you? And if so, how can it be grown successfully? Overview Botanical Name Paeonia ssp. Common Name(s) Tree peonies Plant Type Perennial Shrub Native Area China Hardiness Rating H6 Foliage Deciduous Flowers White, pink, red, peach, yellow blooms When To Plant September-October When To Prune February Tree peonies are members of the Paeonia genus which have woody stems and a shrubby form. The tree peonies grown in gardens are often hybrids, derived after long cultivation and through cross-breeding from wild Chinese species in the Moutan group of Paeonia.1 Tree peonies are prized for their attractive leaves and especially for their large, bowl-shaped blooms. Tree Peony Vs Peony – What’s The Difference? The difference between tree peonies and other peonies is that these are shrubs, with woody stems, rather than herbaceous perennials. They will lose their leaves in winter, but unlike other peonies, will not die back to the ground. Common Varieties When choosing a tree peony, one of the most important considerations for most gardeners will be the colour and form of the flowers. There are single, semi-double and double-blooming cultivars available which come in a huge range of different colours and shades. Some great varieties to consider include: P. delayavi var. ludlowii P. ‘Duchess of Kent’ P. ‘Duchess of Marlborough’ P. x lemoinei ‘High Noon’ P. x lemoinei ‘Souvenir de Maxime Cornu’ P. ‘Reine Elizabeth’ P. ‘Rockii’ P. ‘Shimane Sedai’ P. ‘Shimanishiki’ P. ‘Showanohokori’ P. x suffruticosa ‘Renkaku’ P. rockii How To Grow Tree Peonies Gardeners will not typically grow tree peonies from seed. Most of the tree peonies offered for sale are grafted onto herbaceous peony rootstock. You should be able to see the raised graft scar when you purchase your plant. However, should you wish to grow these plants from seed, you can do so both with species like Paeonia delavayi and with hybrids. Note, however, that hybrids grown from seed will not breed true, so may not grow up to resemble the parent plant, and they are often inferior. However, you might still see some interesting results. Growing From Seed To grow from seed: Collect seed when pods split open in late summer or autumn. Collect the black seed, which is viable. Soon after collecting the seeds, sow them 2.5cm deep in containers of seed compost. Cover the compost with a layer of grit and place them in a cold frame, or sheltered spot outside (at the base of a wall, for example). Make sure the medium does not dry out in summer and rodents cannot eat the seeds. Peony seeds are doubly dormant – roots emerge after the first winter, but stems and leaves only after the second winter. You will have to be patient as seedlings will take up to 5 years to reach flowering size. When To Plant Tree peonies should be planted in the autumn months, however, you can also plant them in winter or the early spring. Just make sure to avoid planting any later than early spring as the plants may fail to establish when the weather is too warm and dry. Where To Plant Tree peonies require a sunny position or one with light shade. It is important to avoid frost pockets since, though hardy, their developing buds can be damaged by late frosts. You should also site a tree peony in a sheltered spot where it will not be damaged by strong winds. “Walled gardens are ideal for tree peonies but any area of a garden that is protected by structures or trees and shrubs and are south-facing should work well,” says Colin Skelly, a Horticultural Consultant. “Work in plenty of organic matter to heavy clays or sandy soils to improve drainage and moisture holding respectively.” Choose a position where there is neutral, free-draining yet humus-rich soil for best results. Avoid planting in soil with heavy clay that becomes waterlogged unless and until it has been amended with plenty of organic matter like homemade compost or well-rotted manure. Graft Union It is important when planting a tree peony that you have purchased to look for the graft union. You should see this as a slight bulge close to the base of the stem. In this case, the graft union should be below the soil surface. Ideally, aim to make sure that the graft union is around 15cm below ground level. This helps the grafted plant to develop roots of its own. Water the tree peony in well, then mulch around your new shrub with some organic material to conserve moisture and provide slow-release fertility. Just make sure that the mulch is not piled up around the stem as this can cause it to rot. Tree Peony Care Light Tree peonies are happy in a sunny spot as long as the soil conditions are right, and can also thrive in light shade. Temperature & Humidity These plants are H6 hardy in the UK and are able to withstand even harsh winter conditions. However, as mentioned above, they may be damaged by strong winds or late frosts. Watering Tree peonies should be watered regularly during dry spells during their first summer, but once established, their deep roots mean that they will not have high watering needs and routine watering will not be required. Deadheading Dead flowers can be removed after flowering if you do not wish to collect seed. Feeding In reasonably nutrient-rich soils, applying a good quality organic mulch and replenishing this each year in spring should be sufficient enough to meet this plant’s nutrient needs. If growth seems poor, you can also add a balanced organic fertiliser in spring. Overwintering These plants are fully hardy and will not need winter protection. They will lose their foliage, but their woody structure of branches will remain in place until the following year. Container Growing Tree peonies are relatively large and deep-rooted plants once mature, and so are not necessarily the best choice for long-term container cultivation. If you are looking for peonies to grow in pots then herbaceous types are likely to be better options. Pruning Very light maintenance pruning only is required. Remove any dead shoots in winter, cutting back to a healthy bud. Occasionally, you may wish to prune to remove flowering shoots in summer, or in the autumn after seeds (if you wish to collect them) have matured, but this is not usually required. References 1. Zhou, S., Zou, X., Zhou, Z., Liu, J., Xu, C., Yu, J., Wang, Q., Zhang, D., Wang, X., Ge, S., Sang, T., Pan, K., & Hong, D. (2014). Multiple species of wild tree peonies gave rise to the ‘king of flowers’, Paeonia suffruticosa Andrews. The Royal Society Proceeding B: Biological Sciences, 281(1797), 20141687. https://doi.org/10.1098/rspb.2014.1687
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