Growing
Cannas Work Well In Pots - You Can Move Indoors To Protect The Rhizome In Cold Periods
IN THIS GUIDE Can You Grow Canna Lily In Pots? Choosing Growing Pots Potting Compost For Canna Planting Canna In Pots Potted Canna Care Cannas display a profusion of fan-shaped leaves that are usually in rich tones of green but many varieties feature dramatic foliage in red and bronze shades – with some even flaunting variegated striped leaves. They are irregularly shaped and have wavy, ruffled petals. For the most part, they are seen in warm, vibrant tones but elegant whites and soft yellows are also available. These plants usually grow to 1-1.5m in height but can be taller if the right conditions are provided. Can You Grow Canna Lily In Pots? Yes you can! In fact, if you are located in a region with a hardiness of H4 (most of the UK) or colder, then it will probably be to your advantage to do so. That’s because canna rhizomes must be overwintered indoors in cold parts of the country, and a pot can simply be moved as-is indoors. Here is a canna I grew from seed and placed on the windowsill of my bedroom at home: Living in Leeds, I found it highly advantageous to be able to move this to suitable climes during summer and then winter, though it needed regular watering – especially in such a small pot. It has flourished in a north-facing windowsill of my home in the colder months of the year – and grew much faster when placed outside in the summer months. I will transplant this into a much larger pot next year and expect it to flower for the first time. Choosing Growing Pots Cannas require large containers as they are big plants – they grow to at least 1m and 2m tall varieties are not uncommon. Though small pots are perfectly suitable for the relatively unusual dwarf cannas, you will need 30-40L pots for full-size canna varieties. Besides size, the container has to be sturdy enough to accommodate the necessary amount of soil and the size and weight of the plant. It must also be strong, so sturdy plastic or ceramic pots are better choices. Whichever type of container you choose, it must have drainage holes of sufficient size and number because very good drainage is required. Potting Compost For Canna Cannas require well-draining, loose soil that is rich and fertile with little clay and that retains moisture. A mixed loam amended with grit, perlite, or both, and with ample organic compost or even some well-rotted manure, will be perfect for these plants. Although these plants tolerate many kinds of soils, blooming will be affected in less fertile soils. Further amending the soil with vermiculite or laying a thin layer of mulch on the surface will retain moisture, which is especially important for outdoor potted Cannas in the summertime. A slightly acidic soil pH is ideal, but not essential. Planting Canna In Pots Canna rhizomes should be planted when the soil temperature is 10°C or higher. Late spring to early summer will work fine in most regions of the UK. As a rule of thumb, rhizomes should be planted about twice as deep as the rhizome is wide, which usually means a depth of 6-10cm. They should be planted horizontally with the eyes upward. If the rhizome has any roots, you know which is the downward side. Cannas are sun-lovers by nature, so full sun is just about mandatory for these plants. Initially, water sparingly just so that the soil becomes moist. Continue doing so until the rhizome sends up stalks and leaves, increasing the amount of water thereafter. As the plant matures, water it generously so that the soil stays moist throughout. How Many Cannas Per Pot? You should plant Cannas one to an appropriately-sized container. They are big plants and also grow very quickly, so they need room to develop their root system. However, you could plant several cannas in a large planter, but they will need to be spaced according to their respective heights and spreads. Most Canna varieties should be spaced by 40-50cm. Potted Canna Care These tropical plants prefer moist soil and soil in containers dries out quicker than that of a bed, so special attention should be paid to watering, especially in hot weather. The soil should not be allowed to dry out and stay dry as moist soil is preferred. Fertilise these plants with a granular controlled-release fertiliser in mid-spring or with a ready-to-pour liquid fertiliser once a month before and during the flowering season. Choose a high-potassium formulation. Canna rhizomes multiply and periodic division is even more important for container-grown plants than those growing in the ground. If rhizomes are allowed to keep multiplying, they will choke one another and compete for the limited nutrients in container soil, and, as a result, plant health and blooming will adversely be affected. In most regions of the UK, cannas need winter protection. If grown in a container, they can be moved indoors into a warmer location over the winter months.
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As A Basic Rule, Sow Violas Indoors Around 10-12 Weeks Before Spring Planting
IN THIS GUIDE When To Sow Violas 1) Sowing Seeds Indoors 2) Sowing Seeds Directly Violas are a varied genus of plants that includes pansies, which are hybrids bred and derived from the Viola species. When we talk about violas in the UK, we are usually referring to the smaller-flowered and typically perennial flowering plants from which pansies were derived, not pansies themselves. Most commonly, we are talking about Viola tricolor or Viola odorata. Both of these can be grown from seed, though the latter can be more challenging and take longer to germinate. When sowing viola seeds, there are two main options: Sow indoors 10-12 weeks before spring planting. Sow directly in early spring or autumn. Difficulty Medium Equipment Required Seeds, seed tray or pots, compost, propagator When To Sow Late winter or early spring When To Plant Out April-May When To Sow Violas Viola seeds can typically be sown indoors around 10-12 weeks before they are planted out into your garden in spring, after the last frost date in your area. There is also the option of directly sowing viola seeds in your garden, which you can do either in the early spring or in the autumn. The natural stratification process can help some violas to germinate more successfully. 1) Sowing Seeds Indoors Start preparing for indoors sowing around 10-12 weeks before the last frost date in your area. Prepare a seed tray or a container by filling it with a seed-starting growing medium. Sow the viola seeds on the surface of the growing medium then cover them lightly with a little more of the growing medium. Make sure the seeds are covered as they require dark conditions for germination. With most species, you can expect germination to take place within 2-3 weeks. Ensure the soil remains moist during the germination process but that waterlogging does not occur. A heat mat or heated propagator can aid the germination process. You should then prick out and pot on seedlings as required. You may need to use grow lights when starting indoors to make sure that the seedlings don’t become weak and leggy due to the lack of light for early sowings. By spring, when the time comes to harden them off and plant them out, they should be close to the size at which they will flower. 2) Sowing Seeds Directly You can also directly sow viola seeds in containers or growing areas outdoors in the autumn or the early spring. When sown in autumn, the seeds will undergo natural stratification over the winter and will then often germinate more successfully come spring. “When sowing directly outside, make sure to accurately mark where you have sown them,” says Master Horticulturist Colin Skelly. “Keeping the area seed-free will be critical to good germination.”
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Viola: Following These Care Guidelines Will Prolong Their Long Flowering Season
IN THIS GUIDE Overview Varieties Where To Plant Growing Requirements Planting Viola Ongoing Plant Care All too often pigeonholed, violas are among the most versatile flowering plants, they are easy to grow and have long flowering seasons. These colourful little blooms are possibly the cutest and cheeriest yet gentlest and most laid-back flowers you can grow just about anywhere in your garden, be it in a bed of their own, around a tree, or in a little corner. In this guide, we will tell you everything you need to know about growing and caring for violas growing in your home and garden. Overview Botanical Name Viola spp. Common Name(s) Viola / Violet / Pansy Plant Type Annual or Perennial Native Area North America and Europe Hardiness Rating H7 (depends on variety) Foliage Evergreen Flowers Small flowers of lots of different colours When To Plant May-August When To Prune May-July Viola tricolor is a herbaceous plant that has rhizomatous roots and grows to 15-25cm in height. It bears a small flower of about 2.5cm that has five petals. It is coloured purple, yellow, and white with dark streaks. These plants are annuals, biennials or short-lived perennials in the wild. Many of their numerous cultivars are evergreens in temperate climates but are all too often seen and treated as annuals. Viola flowers are relatively gentle, laid-back charmers that have been overshadowed over the past several decades by their bigger and bolder siblings – pansies. Varieties Here are some of the most common viola varieties that are grown in the UK. ‘Rose Shades’ All of the following varieties are hardy to H5 or H6. V. ‘Carousel’ V. ‘Bridie’ V. ‘Clementina’ V. Vibrante Series V. Sorbet Series V. ‘Yellow Blue Jump Up’ V. ‘Magnifico’ V. ‘Rose Shades’ V. ‘Bambini Mixed’ V. ‘Penny Peach Jump Up’ V. × williamsiana ‘Floral Power’ ‘Sorbet’ Where To Plant Though Violas are commonly used for borders and edging, a good mix of violas can fill a bed on their own. Violas are also great plants to intersperse amidst taller ones that bear bell-shaped or trumpet-shaped flowers such as daffodils, amaryllis, daylilies, and bluebells. In view of violas’ profiles and habits, they are very well suited for rockeries. Of course, they make the very best potted plants to put on the porch or the patio, or in a window box. Finally, violas have a secret strength: they make delightful indoor plants! Choose the right variety and you can keep a small pot or container of violas on a tabletop or the kitchen window where they will get morning sun. “I also grow violas in the vegetable garden and in the greenhouse as food for the stomach as well as the soul,” shares Horticultural Consultant Colin Skelly. “Violas are increasingly popular as a colourful and edible garnish for salads and regular harvesting keeps them flowering for longer.” Growing Requirements Soil Any type of loamy soil works for violas but the best soil for them is a rich, fertile, slightly acidic soil. Amending your garden soil with about 25% peat-free moss and organic compost will do wonders for your violas. They need free-draining acidic soil and will not do well in alkaline conditions. Light Violas in most regions of the United Kingdom will do best in full sun. Some varieties, like their sibling pansies, will succumb to the summer sun in the warmer regions of the country and these should be grown in part shade. In any case, almost all violas will perform well in a partially shaded site. Planting Viola When and for how long a viola variety will flower depends on the season in which the seeds are sown. Though the sowing season often determines when violas flower, the prime seasons to sow them are sometime in spring and in late summer to early autumn. As a general rule, sow seeds in spring for the plants to flower in autumn, and vice versa. Ongoing Plant Care Watering & Fertilising Evergreen violas that flower through the summer will need more water during hot weather. You do not need to fertilise violas if you have amended the soil with garden compost. Otherwise, and for evergreen varieties in their second year, fertilise them in spring and autumn. You can use slow-release granules or a liquid fertiliser. Pruning The more you deadhead violas, the more profusely they will flower. However, if you would like your violas to self-seed so that you keep getting new plants, allow a good number of flowers to die and go to seed. Common Pests & Diseases Violas that are grown outdoors or indoors are susceptible to powdery mildew, downy mildew, pansy leaf spot, and other fungal diseases. You can minimise the chances that your violas will contract a fungal disease by watering them at the soil level so that the foliage does not get wet. Violas might also be attacked by aphids. If slugs or snails are found in your garden or its vicinity, they will almost surely go for your violas, so be prepared for them.
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Salvia Nemorosa (‘Woodland Sage’) Is An Ideal Wildlife Plant: How To Grow Yours
IN THIS GUIDE Overview Planting Woodland Sage Plant Care Container Growing Companion Planting References Salvia nemorosa (‘Woodland Sage’) is a wonderful option for a wildlife-friendly space. Though non-native, it can thrive in many UK gardens. In this article, you will learn why you may wish to grow this plant, and where to place it if you do. Overview Botanical Name Salvia nemorosa Common Name(s) Balkan Clary / Woodland Sage Plant Type Perennial Native Area Central Europe and West Asia Hardiness Rating H7 Foliage Deciduous Flowers Upright spikes of purple flowers When To Plant May-June When To Prune September-November S. nemorosa is a member of the Salvia (sage) genus. It is a hardy, herbaceous woodland perennial native to broad swathes of Central Europe and Western Asia.1 The name nemorosa refers to the plant’s native woodland grove habitat, meaning ‘of woods’.2 ‘Caradonna’ is the name of one popular cultivar of this plant. It has been rewarded with the RHS Award of Garden Merit and is named on the RHS Plants for Pollinators list. It has dark purple stems and purple-violet stems borne in long, upright spikes. This plant is beneficial for bees and other pollinators due to its nectar-rich flowers. That nectar is available over a long period, as the plants can be in bloom between June and October, providing a bounty of sustenance and attracting beneficial insects all summer long. Bees can see purple and white flowers easily, and the purple blooms of these flowers stand out for them in the summer garden. Butterflies also love this plant, so it is a good addition to a butterfly-friendly garden. “Salvia nemerosa is one of my favourite plants for including in herbaceous plantings for providing a long period of flowering for pollinators,” shares Master Horticulturist Colin Skelly. “As a garden plant, it is also tough and versatile, combing well with many other perennials and grasses and needing little looking after.” Planting Woodland Sage Plant S. nemorosa in May or June and it will grace your garden for a number of years to come. As a herbaceous perennial, it will die back in winter but burst back into new growth each spring. This plant is wonderful on the fringes of a forest garden or woodland space. It also works very well in herbaceous borders, or with other perennial plants in a mixed bed or border planting scheme. Planted around the fringes of a kitchen garden, it can bring in pollinators and other beneficial insects and ensure good pollination rates on common garden crops. How To Plant Out S. nemorosa can be purchased in pots, and if you purchase a plant in autumn, it is best to wait until after the last frost before planting it out. Trim back the plant a little to encourage bushy growth and plant in the ground or container where it is to grow once the risk of frost is passed. Plant Care This hardy perennial can be a great low-maintenance plant for a suitable spot. You should find them an easy and rewarding plant to grow, provided you follow the simple advice below: Aspect A south-facing or west-facing aspect can be ideal for S. nemorosa. Although the plants can cope with partial or dappled shade, a sunny and sheltered location will be optimal. Overwintering S. ‘Caradonna’ is one of the many H7 hardy perennial sages and will survive the winter across the UK, even during harsh winters. Soil Requirements The soil in a suitable spot will be moist yet free-draining. Once established, this plant can be pretty drought tolerant, but cannot tolerate waterlogged soil. Chalk, loam or sandy soil is ideal, and those with heavy clay may find it more difficult to create the right growing conditions. However, even those with clay soil can grow this plant, as long as the soil is amended with plenty of organic matter to improve drainage. Pruning Deadheading flower spikes during the flowering season can encourage further flowers over the long blooming period. The plants may also be pruned back to the ground in autumn after the flowering is done. However, while this keeps your garden looking neat, you could consider leaving dead material in perennial beds and borders in place to provide a habitat for wildlife over winter. Common Pests & Diseases Usually, S. nemorosa is a relatively trouble-free plant to grow. However, it is worth noting that the plant is a favourite with slugs and snails, which can pose quite a threat to young plants in particular. Encourage natural predators like thrushes and hedgehogs to keep down pest numbers, and protect young plants where these are a particular problem. Container Growing S. nemorosa can also be an interesting choice for growing in containers. Since they are fairly compact plants, which will spread to around 50cm tall and 30cm wide, these can work well in pots in a container garden. The key thing to remember if growing in containers is that you will need to water more during dry periods since containers can dry out more quickly. Companion Planting S. nemorosa works very well with other Salvias, which come in a range of colours and heights. They can also be great for underplanting below roses, and a range of other flowering shrubs that like similar growing conditions. These plants also look wonderful with other herbaceous perennials, including but certainly not limited to penstemons, eryngiums, achilleas, nepetas, verbenas and veronicastrums, and also look wonderful alongside ornamental grasses. References 1. Salvia nemorosa. (n.d.). Kew Royal Botanic Gardens. Retrieved March 24, 2023, from https://powo.science.kew.org/taxon/urn:lsid:ipni.org:names:456774-1 2. nemorosa – Translation and Meaning in Almaany English-English Dictionary. (n.d.). Retrieved March 24, 2023, from https://www.almaany.com/en/dict/en-en/nemorosa/
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Talking Super Sage Varieties With The Victorian Salvia Study Group
IN THIS GUIDE Expert-Chosen Varieties 1) S. argentea 2) S. spathacea 3) S. oxyphora 4) S. ‘Royal Bumble’ 5) S. ‘Jezebel’ 6) S. x jamensis ‘Raspberry Royale’ 7) S. ‘Hot Lips’ 8) S. ‘Clotted Cream’ 9) S. splendens ‘Vanguard’ 10) S. officinalis ‘Tricolor’ 11) S. nemorosa ‘Caradonna’ 12) S. rosmarinus ‘Green Ginger’ 13) S. sylvestris ‘May Night’ 14) S. microphylla ‘Heatwave Glimmer’ References Salvias produce flowers that are easy on the eye and there are well over 1,000 accepted species to choose from, according to Kew.1 With this in mind, it can be hard to know where to start. Luckily, we’ve got you covered, as we share some favourites from Lyndi Garnett, the Founder and Coordinator of the Victorian Salvia Study Group. We also share 14 favourites (with pictures) from our editorial team. Expert-Chosen Varieties “Salvias are incredibly diverse, they grow all over the world from coastal South Africa to the high Andes,” says Vicki Weston, owner of Weston’s Salvias. “They are very varied in form and colour so I’m never going to get bored! 600 species and hundreds more varieties of these have been bred over the last twenty years. S. ‘Nachtvlinder’ “They are also extremely long flowering, blooming from late May until the frosts, very low maintenance and beneficial bees and bugs love them.” We asked Vicki to share some of her favourite varieties. S. uliginosa “Asking me my favourite salvia is a bit like asking me who my favourite child is!” she jokes. Her top picks included the hardy varieties: S. ‘Royal Bumble’ (scarlet, pictured below) S. ‘Flower Child’ (pink) S. ‘Nachtvlinder’ (purple, pictured above) S. × jamensis ‘Javier’ (violet) S. uliginosa (blue, pictured above) And some tender salvias that Vicki loves are: S. involucrata (pink, pictured below) S. fulgens (red) S. corrugata (purple) “There are too many to have favourites,” agrees Lyndi Garnett. However: “In summer, I like all the small-leaf Salvia microphylla and S. greggii types because of all their bright colours.” S. microphylla “When autumn comes around, all the cerise and crimson flowers contrast beautifully with the purples and bright blues and, in winter, all the tall large leaf varieties come to life, some reaching up to 4m in height and spread. S. greggii “Then all the herbaceous varieties burst forth and the small-leaf salvias come to life, and so it begins again.” A medley of Lyndi’s other top picks include: S. madrensis S. involucrata S. wagneriana And if these aren’t enough, we sample 14 additional varieties below – a hand-picked mix of the popular and the rare in all colours of the rainbow. 1) S. argentea COMMON NAME(S): silver sage HARDINESS RATING: H5 FOLIAGE: grey and silver FOLIAGE TYPE: semi-evergreen FLOWERS: white FLOWERING SEASON(S): summer SUNLIGHT: full sun EXPOSURE: exposed / sheltered With a height of about 90cm and a 50cm spread, ‘Silver Sage’ is a very tidy plant in more ways than one. The ‘argentea’ or ‘silver’ in its name refers to the cool, patently silvery-green shade of its leaves that are irregularly ovate and sport thread-like hairs. The flowers are white and are produced during a shortish season in late summer. This species has received the RHS Award of Garden Merit. 2) S. spathacea COMMON NAME(S): pitcher sage HARDINESS RATING: H4 FOLIAGE: green FOLIAGE TYPE: deciduous FLOWERS: red and pink FLOWERING SEASON(S): summer / autumn SUNLIGHT: full sun EXPOSURE: sheltered Among the most unusual and sparklingly colourful of salvias, pitcher sage comes in at a height and spread of just under 1m. The leaves are like oblong arrows, amusingly crinkled, and quite aromatic. They are purplish-pink with a purplish-maroon understructure. This species is also a recipient of the RHS Award of Garden Merit. 3) S. oxyphora COMMON NAME(S): fuzzy Bolivian sage HARDINESS RATING: H3 FOLIAGE: green FOLIAGE TYPE: semi-evergreen FLOWERS: pink and red FLOWERING SEASON(S): summer / autumn SUNLIGHT: full sun / partial shade EXPOSURE: sheltered Rising up to 1.5m in height, frost-tender Fuzzy Bolivian Sage gets its name not from its foliage, but, from its flowers, as the 4cm nub-like blooms are covered in a fine fuzz. They are a bright pink to cherry red and are borne in spikes, the overall effect being uniquely decorative. These blooms are seen from midsummer into autumn. This delightful and rare import also features brilliant green leaves that are oval-to-lanceolate. 4) S. ‘Royal Bumble’ COMMON NAME(S): sage ‘royal bumble’ HARDINESS RATING: H4 FOLIAGE: green with purple stems FOLIAGE TYPE: evergreen FLOWERS: red FLOWERING SEASON(S): summer SUNLIGHT: full sun EXPOSURE: sheltered With a bushy habit emphasised by the roughly equal dimensions of its height and spread of about 75cm, ‘Royal Bumble’ is an exceptionally popular cultivar. The foliage is deliciously aromatic and is of a brilliant, almost vivid, green shade. The clawed flowers are awesomely-coloured, being rich vermilion with gradations into orange and red. These vibrant flowers bloom from late spring to early autumn and the variety has been awarded the RHS Award of Garden Merit. 5) S. ‘Jezebel’ COMMON NAME(S): sage ‘jezebel’ HARDINESS RATING: H3 FOLIAGE: green FOLIAGE TYPE: evergreen FLOWERS: red FLOWERING SEASON(S): spring / summer / autumn SUNLIGHT: full sun EXPOSURE: sheltered ‘Jezebel’ produces larger-than-average bright red flowers displayed on racemes. Additional charms include the ovate leaves which are petite and of a rich, deep green shade and the extended blooming season that starts in late spring and finishes in mid-autumn. It grows to about 90cm and is (yet another) recipient of the RHS Award of Garden Merit. 6) S. x jamensis ‘Raspberry Royale’ COMMON NAME(S): sage ‘raspberry royale’ HARDINESS RATING: H4 FOLIAGE: green FOLIAGE TYPE: evergreen FLOWERS: red FLOWERING SEASON(S): summer / autumn SUNLIGHT: full sun EXPOSURE: sheltered Continuing with the red theme and presenting another cultivar that is true to its name, ‘Raspberry Royale’ features perfect raspberry-red flowers. They are double-lipped and, although on the small side, occur in spellbinding abundance on racemes, and are even produced over a lengthy blooming season from summer into autumn. This sub-shrub has greyish-green lanceolate leaves that are very pleasantly aromatic. 7) S. ‘Hot Lips’ COMMON NAME(S): sage ‘hot lips’ HARDINESS RATING: H5 FOLIAGE: green FOLIAGE TYPE: evergreen FLOWERS: white and red FLOWERING SEASON(S): summer / autumn SUNLIGHT: full sun EXPOSURE: sheltered One of those red hot hit varieties, ‘Hot Lips’ is supremely popular. At an equal height and spread of about 1m, this bushy plant’s foliage does not even get a second billing as the flowers steal the show. The clawed blooms are a brilliant red in the early part of the season and often come up white when the show closes in late autumn. However, in mid-season, they are at their bi-coloured best, displaying a bright red and hard white. 8) S. ‘Clotted Cream’ COMMON NAME(S): sage ‘clotted cream’ HARDINESS RATING: H4 FOLIAGE: green FOLIAGE TYPE: deciduous FLOWERS: cream FLOWERING SEASON(S): summer / autumn SUNLIGHT: full sun EXPOSURE: sheltered A deciduous perennial that reaches up to 70cm tall and has a bushy habit, ‘Clotted Cream’ has deep green ovate leaves that are remarkably aromatic. The clawed and lipped flowers are a rich creamy white colour. Their blooming habits are variable, but they will certainly bloom throughout the summer months. 9) S. splendens ‘Vanguard’ COMMON NAME(S): scarlet-flowered sage ‘vanguard’ HARDINESS RATING: H3 FOLIAGE: green and red FOLIAGE TYPE: deciduous FLOWERS: red FLOWERING SEASON(S): summer / autumn SUNLIGHT: full sun EXPOSURE: exposed / sheltered A clump-forming, upright cultivar that grows to a mere 30cm in height, ‘Vanguard’ is a tender but wonderfully floriferous variety. In summer it bears lush spikes of scarlet flowers, which it keeps producing until some time in autumn. Reddish bracts emphasise the brilliant red colourations of this joyfully decorative variety. This variety has been awarded the RHS Award of Garden Merit. 10) S. officinalis ‘Tricolor’ COMMON NAME(S): sage ‘tricolor’ HARDINESS RATING: H5 FOLIAGE: cream, green, grey, silver and purple FOLIAGE TYPE: evergreen FLOWERS: blue FLOWERING SEASON(S): summer SUNLIGHT: full sun EXPOSURE: sheltered Though it produces pretty little blue flowers in summer, Tricolor’ is a salvia that is desirable for its very ornamental foliage. Those 3 colours with which the variegated and aromatic leaves are decorated are shades of green, cream, and rose-purple, the last hue appearing usually only on young leaves. What’s more, it is a hardy evergreen so you can enjoy this plant’s beautiful foliage even in the grey of winter. 11) S. nemorosa ‘Caradonna’ COMMON NAME(S): Balkan clary ‘caradonna’ HARDINESS RATING: H7 FOLIAGE: grey, green and silver FOLIAGE TYPE: deciduous FLOWERS: purple FLOWERING SEASON(S): summer SUNLIGHT: full sun / partial shade EXPOSURE: exposed / sheltered A super-hardy perennial, ‘Caradonna’ is surely salvia royalty. Immensely popular, its flowers are a lustrous royal purple verging on violet. These small but brilliant blooms are held aloft on spiky racemes and are seen for the better part of summer. It reaches a touch under 50cm and has greyish-green foliage. 12) S. rosmarinus ‘Green Ginger’ COMMON NAME(S): rosemary ‘green ginger’ HARDINESS RATING: H4 FOLIAGE: green FOLIAGE TYPE: evergreen FLOWERS: white and blue FLOWERING SEASON(S): spring / summer / autumn SUNLIGHT: full sun EXPOSURE: exposed / sheltered Leading the way among the edible sages is, of course, rosemary, and ‘Green Ginger’ is one of the best picks among the many shrubby evergreen cultivars. It is a bushy plant that grows to nearly 1m in height. The narrow leaves are deliciously aromatic and make for an unbeatable kitchen herb. It produces lovely pale blue and white flowers in clusters from late spring to the end of summer. 13) S. sylvestris ‘May Night’ COMMON NAME(S): wood sage ‘mainacht’ HARDINESS RATING: H7 FOLIAGE: green FOLIAGE TYPE: deciduous FLOWERS: blue FLOWERING SEASON(S): summer SUNLIGHT: full sun EXPOSURE: exposed / sheltered ‘May Night’ is a super-hardy deciduous perennial that rises up to 1m and around half the spread. Its aromatic foliage is of that cool, deep, greyish-green hue that typifies the sages. It produces flowers all through the summer that are borne thickly on racemes and are of a brilliant purple hue that catches and holds the eye. Another recipient of the RHS Award of Garden Merit. 14) S. microphylla ‘Heatwave Glimmer’ COMMON NAME(S): sage ‘heatwave glimmer’ HARDINESS RATING: H4 FOLIAGE: green and purple FOLIAGE TYPE: evergreen FLOWERS: cream FLOWERING SEASON(S): summer / autumn SUNLIGHT: full sun EXPOSURE: sheltered A shrubby evergreen with a bushy habit and a height and spread of 1m, ‘Heatwave Glimmer’ displays colour in unexpected places: it has visibly purplish stems and sepals, and young leaves are often also tipped or tinged with purple. In contrast, the clawed flowers that resemble birds are creamy white, often with a pink flush. These classy, refined blooms appear from early summer and clear into autumn. References 1. Salvia L. (n.d.). Kew Royal Botanic Gardens. Retrieved March 28, 2023, from https://powo.science.kew.org/taxon/urn:lsid:ipni.org:names:30000096-2#children
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Salvias Will Grow Happily In Containers (And It's Essential For The Tender Ones)
IN THIS GUIDE Can You Grow Salvia In Pots? Choosing Suitable Containers Choosing Compost Potting Up Salvia Pot-Grown Salvia Care Sage plants’ unusual, irregularly-shaped flowers are as much a treat to the eyes as the zesty leaves that are a treat to the palate in pot roasts and stuffings. You may be wondering if you can grow sage in containers. Luckily for you, this article has all the answers. Can You Grow Salvia In Pots? Yes, you can, and if you are growing salvia varieties that are hardy only to H3, you probably should. That way you won’t have any trouble protecting the frost-tender plants over the winter, as Vicki Weston from Weston’s Salvias explains: “Salvias will grow happily in containers and, for the tender varieties, many of which are still in spectacular flower in November, it’s essential.” Choosing Suitable Containers I’d recommend you choose a terra-cotta pot with drainage holes. It’s best to avoid containers made of plastic and other synthetic materials. As for the size of the container, this depends on the present size of the plant and, eventually, on its ultimate height and spread. “I think that many people use containers for salvias because they are nervous about their plants surviving over winter,” Vicki says. “Remember that shrubby types grow thousands of feet up in the South American mountains, so they are tough. “Hot Lips, Royal Bumble and lots of other varieties are hardy to -10°C and, ironically, as a container is colder, they are less safe in the winter in a pot than in the ground!” Salvia varieties’ ultimate heights range from a compact 0.3-2m, so the size of the container will be very variable. I’d recommend choosing a container with a height that is about half as much as the current height of the plant, or even a little more. Salvia roots grow relatively quickly and it has a well-spread root system, so be sure to pot on or consider using a bigger pot in the first place. Choosing Compost Salvias perform best in moderately fertile, but not overly rich, soil with some organic content, but they are susceptible to root rot so excellent drainage is non-negotiable. “Choose a very good potting soil with little organic matter so the soil doesn’t become sour due to a lack of oxygen,” advises Lyndi Garnett, from the Victorian Salvia Study Group. For all salvia except Rosemary varieties, you can’t go wrong with a high-quality outdoor or all-purpose potting mix. Otherwise, loose soil that is a mix of grit or perlite, sand, and organic compost will do very well for most salvia. For Rosemary varieties, less fertile soil such as a balanced loam should be used. The soil should be kept moist, though it should be allowed to dry out between waterings. Potting Up Salvia Potted Salvia plants will need to be potted up until they attain their ultimate size. Nearly all salvias should not be left in their original containers permanently as they can become rootbound with resultant stress on the plant, causing it eventually to die. Whether you pot on or transplant your salvia, a sunny May morning would be ideal. For most Salvia varieties we suggest that the new pot should be two sizes up from the current one. Lightly water the potted salvia, then dig a planting hole that is a little deeper and a little wider than the plant’s pot. Remove the Salvia with the soil from the pot, then gently shake out some of the soil from the roots. If the roots are well spread, place the crown in the hole to transplant, but if they are rootbound then you will need to loosen the roots and spread them out before placing into the new container. A good way to do so is to dip the root system into a tub of clean, cold water, gently swish them around, and separate them. Backfill around the hole, firm up the soil and water thoroughly. How Many Salvia Can You Plant Per Pot? For full-grown perennial salvia, I’d suggest that you grow only one per pot so that the pot’s dimensions are appropriate for the given plant’s size. Most salvia varieties require soil nutrients to produce the most eye-catching blooms and the most delectable leaves, so it is wise to let each plant play by itself. “Pots can be positioned in various locations – shade or sun,” says Lyndi. “Most like a sunny sheltered position, but it can vary, so check the preferences for the varieties you are growing.” Pot-Grown Salvia Care For the most part, salvia in pots should be kept in full sun in a sheltered spot. Varieties that are hardy to H6 or H7 may be kept in an exposed location. Whether your salvia plants are in containers or in open ground, regular deadheading will prolong blooming. During hot summers, keep an eye on salvia containers kept in full sun. If the plant is drooping, increase the frequency of watering and shift it to a partially sunny location where it will get dappled or filtered sunlight. “Water your potted salvias around once a week with regular feeding,” recommends Lyndi. “Make sure there’s lots of air around the pot and that you don’t over water.” Fertilise these plants once a year in the spring with a balanced controlled-release fertiliser, taking care to use the product in proportion to the size of the plant and the container. As salvia varieties vary widely in hardiness from frost-tender H2 plants such as Salvia dombeyi (giant Bolivian sage) all the way to fully hardy H7 ones such as Salvia x superba (hybrid sage) – whether or not winter care is required will be up to the particular variety. “Know your plant – perennial or herbaceous,” advises Lyndi. “If it becomes winter dormant, it is herbaceous and should be overwintered accordingly.” In general, varieties that are not hardy in your region should be overwintered indoors or kept in a greenhouse.
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Primrose Are Notoriously Difficult To Grow From Seed And Are Only Viable For 2-3 Years
IN THIS GUIDE When To Sow Primula 1) Source & Store Seeds 2) Prepare Your Seed Tray 3) Sow The Seeds 4) Place Outdoors 5) Prick Out & Pot Up 6) Overwinter Primroses are extremely easy and popular options as summer bedding plants, but most are notoriously difficult to grow from seed. Even though it might be challenging, it is possible to grow many of your favourite primulas this way. To grow primrose plants from seed: Keep seeds in the fridge until required. Prepare a seed tray filled with seed compost. Sow seeds thinly on the surface of the compost. Place in a shady spot outdoors, with protection from pests. Wait until seedlings have at least four leaves, then prick out and pot up seedlings into individual pots. Overwinter in pots in a frost-free but reasonably cool location. Learn more about this entire process below. When To Sow Primula Many varieties of primula, including varieties of Polyanthus and Auricula, are best sown from February to April. Some light frost can actually help germination, but you should avoid planting too early, and in colder areas, hold off until April. Sow your seeds any time before the end of May and you should still see some flowers the following year. Difficulty Hard Equipment Required Seed, seed tray or pots, growing medium, greenhouse or undercover area When To Sow February – April 1) Source & Store Seeds It is important to note that some varieties of primula are far more likely to germinate successfully than others. You can purchase seeds and should follow the seed-starting suggestions given for the specific type and cultivar. In some cases, you might also be able to collect seeds from primroses you are growing, as long as you have not deadheaded and have allowed the plants to go to seed. When the seeds arrive or when you collect them, place them in a screw-top jar in your fridge, where they should remain viable for 2-3 years. 2) Prepare Your Seed Tray Make sure that you choose your growing medium carefully. Primula seedlings can be very sensitive to mineral salts contained in fertilisers which are found in some seed mixes, so choose a high-quality seed-starting compost. Look for or make one with good aeration that is as fibrous and gritty as possible. Make sure your compost is not too fine or it may become compacted with watering. 3) Sow The Seeds Seeds should be sown thinly on top of the medium, then gently pressed against the surface and not covered. They need light to germinate. Some which germinate more slowly can be sown onto a thin layer of very fine grit over the compost. Water the seeds in with a fine sprinkling, then place a perforated lid over the tray to offer protection from pests. 4) Place Outdoors Place the covered tray outside in a shady location, not under glass. Under glass, temperatures can be too warm, even in spring. Ideally, temperatures should be maintained between 12-15°C for germination to take place, but periods of freezing and thawing are required beforehand, so it is best to sow as early as possible. Primroses should germinate and sprout within around 3 weeks, but some types, like Auricula and Sieboldii, can take up to 6 weeks. 5) Prick Out & Pot Up Prick out the seedlings only once they have developed at least 4 true leaves. Pot up each of the seedlings that have germinated successfully into their own individual pots. Water as needed and check regularly. 6) Overwinter Keep the young plants in a cold frame or in a cool but sheltered position over the following winter. Plant out your young primula the following spring and they should flower that year, a year after sowing. “You will find Primulas are susceptible to fungal issues like Botrytis cinerea (grey mould),” shares Master Horticulturist Dan Ori. “I spray a preventative anti-fungal treatment regularly on young and potted plants. “Although there is no product that advertises that it prevents Botrytis available to the home gardener, a general fungicide should be effective and yes, you can now get an organic fungicide spray (look out for the green bottle).”
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Why You Should Be Deadheading Snapdragons Throughout Their Flowering Season
IN THIS GUIDE When To Deadhead 1) Pinch Off Spent Flowers 2) Cut Entire Stalks 3) Cut Back Delightful snapdragons are among the most popular garden plants, thanks to their unusually shaped flowers in thick bunches on upright spikes. They also come in a remarkable array of hues and shades, including sunny yellow, soft pink, and intense maroon. No matter which variety you go for, you will find some benefits to deadheading snapdragons. Deadheading spent blooms spurs more profuse blooming as it directs the plant’s energy to focus on producing new blooms. Deadheading Snapdragons is a straightforward process: Pinch off spent flowers individually. Cut off entire stalks when the majority of their flowers are wilted or dead. Cut back the plant once during the season to stimulate fresh growth and renewed blooming. This process is explained in more depth below. Difficulty Easy Equipment Required Secateurs When To Deadhead Throughout flowering season When To Deadhead Snapdragons should be deadheaded during the flowering season as a regular and ongoing gardening task. During this season, inspect your plants about once a week or so. 1) Pinch Off Spent Flowers If you see a few fading or wilted flowers on a stalk, pinch them off with your thumb and forefinger. Make sure to remove them from where the flower attaches to the main stalk so that you also remove any developing seed pod. 2) Cut Entire Stalks If you see that the great majority of flowers on a stalk are fading or wilted, use secateurs to cut off the entire stalk at its base near where it rises from the plant. 3) Cut Back After the first flush of blooms seems to be over in mid-to-late summer or if the plant fails to flower satisfactorily in the first place, cut it back to about 30-50% of its current growth. Doing so will most probably stimulate fresh growth and bring forth a fresh flush of blooms. “Deadheading is a time-consuming task but rewards you with more and later flowers,” shares Colin Skelly, a consultant Horticulturist. “With taller cultivars, it will also help to prevent the risk of the plants being blown over. “In small gardens, this attention to detail really helps to get more out of your space.” Leaving blooms will typically result in seed pods that you can collect later in autumn. Make sure to water the plant well after cutting back.
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Did You Know Snapdragons Can Be Sown In Late Autumn For Larger Plants Next Year?
IN THIS GUIDE When To Sow 1) Source Antirrhinum Seeds 2) Sow Snapdragon Seeds 3) Prick Out Seedlings 4) Plant Out In Full Sun Antirrhinums, or snapdragons, are cheerful annuals that are well-known cottage garden favourites and work well in many different garden schemes. Growing snapdragons from seed is a relatively easy process: Collect or select your seeds. Sow into a peat-free, seed-starting growing medium then cover over lightly and water. Prick out and pot up your seedlings once they have true leaves and are large enough to handle. Overwinter under glass if sowing in late summer or autumn, then harden them off and plant them out in a sunny location with free-draining, fertile soil after the last frosts in your area. See our video for an easy visual demonstration of this process: When To Sow Though you can also sow seeds in March, late summer or early autumn is generally considered to be the best time to sow snapdragon seeds. Seeds that are sown in August or in September and overwintered in a greenhouse or cold frame will become larger plants and these will typically flower earlier than those which are sown in the spring, often beginning to bloom in May. Seeds sown in March will typically flower from June through to around September. Difficulty Easy Equipment Required Seeds, seed tray or pots, propagator When To Sow March or August-October When To Plant Out May-June 1) Source Antirrhinum Seeds Of course, you can purchase snapdragon seeds. However, you might also consider collecting seeds from snapdragons you already have in your garden. The seeds of most snapdragons will not come true from seed, so seedlings might not grow up to look like the parent plant. However, you can have some fun discovering what does emerge. 2) Sow Snapdragon Seeds Sow your snapdragon seeds on the top of a seed tray filled with a suitable seed-starting compost or moist yet fine, friable and free-draining mix. Press the seeds in gently to make sure they are in contact with the growing medium and cover them very lightly with more of the compost. Water lightly but make sure that excess water can drain away. Cover the tray with a propagator to keep in moisture and wait for the seeds to germinate. You can place the tray in a greenhouse or on a sunny windowsill. 3) Prick Out Seedlings Once the seedlings have germinated, have grown their first true leaves and are large enough to handle, take each one and place it into its own small pot. “Don’t be tempted to transplant seedlings too early,” warns Colin Skelly, a skilled Horticulturist from Cornwall. “The first leaves you will see are the seed leaves and draw on the energy in the seed. “The first true leaves will arrive later and will often look different to the seed leaves. The root system will also have begun to develop. “The plant can now grow on its own resources and will benefit from its own pot space.” Place these in a sheltered spot, or in a greenhouse or cold frame if you have one. 4) Plant Out In Full Sun Once all danger of frost has passed in your area, plant out your snapdragons into their final growing positions in your garden. This should be done in May or June. They will do well in well-drained, fertile soil in full sun. You can grow them on in larger containers if you prefer, or if you do not have a suitable space, in a bed or border.
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