Grow: Salvia

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15 Feb 2019

When we asked nurseryman Chris Cuddy to share his expertise and his favourites from this family of long-flowering, easy-care plants his big challenge was what to leave out!

Salvias are a diverse group of plants with almost 1000 species recorded and many more hybrids and cultivars on offer. Half are from Central America, with the rest distributed through Asia, Europe, the Mediterranean and Africa. They vary in height from 30cm to more than 3m high and wide, so there is one for every part of the garden. Generally salvias are happy in any well-drained garden soil in full sun. Most are tolerant of periods of dry, especially the S. microphylla and greggii types. 

Select species

Salvia nemorosa (confusingly also known as S. x sylvestris and S. x superba) are herbaceous plants from Central Europe and Western Asia that grow from a central base of foliage and produce multiple spikes of densely packed flowers that are most commonly blue or purple. They have been cultivated for centuries and look fabulous underplanted with spring-flowering bulbs or among other mid-sized perennials. 

Salvia leucantha is from temperate and sub-tropical conifer forests in central Mexico. In its natural form it features a purple calyx with a white flower, and grows to about 1.2m tall. Other forms areavailable: one with deep purple flowers and calyxes; an all-white form; and a form with pink flowers emerging from white calyxes. Similar in requirements to Salvia leucanthais Salvia Mexicana,which features deep royal blue flowers. The cultivar 'Limelight' has lime green calyxes.

Salvia microphylla and Salvia greggii types are well-suited to the average garden as they tend to be smaller and more compact. Many varieties flower from spring through to late autumn. Choose almost any colour: white, ‘White Hot’; soft yellow, ‘Iced Lemon’; orange, ‘Coral’, ‘Pumpkin’, ‘Sensation’; crimson ‘Silas Dyson’, ‘Margaret Arnold’; red, ‘Royal Bumble’; pink, ‘Raspberry Royal’, ‘Angel Wings’, ‘San Carlos Festival’, ‘Musk Pink’, ‘Cyclamen’; and purple, ‘Superior Purple’, ‘Christine Yeo’.

There are also winter-flowering salvias, including Salvia karwinskii, S. wagerianaand S. dorisiana.Thesegrow up to 2m tall and are well-suited to frost-free climates where they add a colour to what can be a monochromatic time of the year. 

And there are so many more to try! Some favourites: Salvia buchananii, the velvet slipper sage from Mexico; Salvia taraxicifolia, the dandelion-leaved sage, which is a fragrant species from Morocco; Salvia azurea,a blue-flowered form from the North American prairies; and Salvia canariensis candidissima,with white wooly leaves and mauve flowers from the Canary Islands. And for something really different, Salvia forsskaolii, the woodland sage from Bulgaria, which is happy in full sun or full shade. 

 

Pruning

Salvias sometimes need a prune to help them stay tidy and compact. The leaf size is a good guide as to how they should be pruned. The small-leafed forms can be cut back by a third to a half if actively growing and getting too large or untidy. If, like me, you get frosts, wait until spring when the main risk of frost is gone before pruning. 

Herbaceous types that die down in winter, such as Salvia nemorosa, can be pruned in summer after their first flowering. This may lead to another flush of flowers in autumn. They can then be pruned to the basal foliage over winter. 

The large-leaved and taller forms should be pruned after flowering; this may be autumn, winter or spring depending on the species. In frosty areas, they can be pruned at the start of winter and then mulched or left until spring when the main frost risk has passed. 

 

Propagation

The shrubby varieties of salvia are fairly easy to propagate by cuttings. Select strong growths about 5-10cm long and remove the bottom set or two of leaves. Remove any flowers or buds. Dip the cutting in commercial rooting hormone gel or honey and place in a pot filled with a good propagation medium. This can be seed raising mix or a 50/50 mix of course sand and coir peat. Cover the pot with a plastic bag and keep in a bright, warm spot, out of direct sunlight and in warm weather. Roots will appear in a few weeks. 

 

In my garden

I use salvias in different ways in different parts of my garden. The soft pink and relatively low-growing Salvia ‘Angel Wings’ combines beautifully with soft blue catmint. I like the bright hot pink of Salvia 'San Carlos Festival' with the similarly bright Echinacea 'Cheyenne Spirit', and contrast the deep purple Salvia nemorosacultivars with the bright yellow flowering Phlomis russeliana. I have the taller salvias 'Anthony Parker' and 'Meigans Magic' planted behind the rose ‘Sally Holmes’, as the blue salvia flowers are a fabulous foil for the white/soft peach flowers of the rose. Lining a garden path leading from the lawn I have massed Salvia leucantha 'White Velour' and 'Pink Velour' and they make a stunning autumn show. 

 

Chris Cuddy owns and operates Perennialle Plants Nursery in Canowindra and offers the plants mentioned here by mail order via perennialle.com.au. 

Words: Chris Cuddy