Star of the season: Daylilies
The Daylily flowers for a day; for lots of days
Here Deirdre Mowatt tells us all about our summer star of the season
Words & images: Dierdre Mowatt
Hemerocallis ‘Ballingarry All Stars’ has mini flowers on tall stems
Daylilies must be one of the plants with the most cultivars in the world! There are more than 80,000 registered cultivars of these clump-forming perennials (many with rather bizarre names, such as 'Crocodile Tears' and ‘Mad Dogs and Englishmen’!). The original species come from China and Japan, and some of these are still worth growing, such as double, orange-flowered Hemerocallis fulva 'Flore Pleno' and fragrant, yellow-bloomed Hemerocallis lilio-asphodelus.
Nowadays, every possible colour daylily has been bred (except for absolute pure white and true blue). Flower sizes vary from true miniatures (less than 7.5 cm across) to large-flowered ones 11 cm or wider. Flower shapes also vary, from the basic trumpet shape to spidery-looking ones, star shapes, triangles, full circle formations and doubles. Many have contrasting coloured 'eye-zones' and throats, which give a dramatic look.
There are early-, mid- and late-blooming varieties, with the peak display being around November and early December. A lovely orange-red one I have called 'August Flame' flowers around January, providing welcome summer colour.
The elegant spider-flowered form of Hemerocallis ‘Green Dragon’
In the garden
The flamboyance of larger-flowered daylilies suits gardens with shrubs and/or warm-climate perennials such as salvias, dahlias and cannas. One of my favourites of these is ‘Black Ambrosia’, with sultry purple-black blooms. Spidery-looking daylilies are very elegant: I particularly like the lime-yellow cultivar ‘Green Dragon’. Miniature-flowered daylilies are a delight in cottage gardens. I am fond of ‘Ballingarry All Stars’, with petite tawny-orange blooms on tall stems. Golden-flowered ‘Stella de Oro’ is a well-known miniature.
Daylilies forms clump of strappy, arching leaves. There are evergreen, semi-evergreen and deciduous types. The evergreen ones seem to do best in the warm temperate climates. Though the flowers are open only for a day, a well-established clump will have many blooms, providing long-lasting colour.
Daylilies enjoy a sunny, well-drained position in soil improved with organic matter, though preferably not animal manure, which can rot the crowns. The crown should be planted level with the top of the soil. They enjoy regular water during their growing season, but will cope quite well with dry spells. Keep the plants well mulched to retain moisture, but don't let the mulch touch the crown. It is possible to grow daylilies in containers, especially the lower-growing cultivars.
Regular applications of liquid fertiliser during the growing season are beneficial. The leaves can be trimmed in mid-winter if looking scruffy. To maximise flowering, the clumps are best divided every three years in autumn, and the fleshy roots replanted in fresh soil. Aphids can be tackled with horticultural oil or even soapy water. Slugs and snails need to be guarded against. A new threat to daylilies is rust: yellow or orange pustules appearing on the leaves during warm, humid weather. I remove the affected foliage at ground level at the first sign of the spots, and put it in the green waste bin. New leaves tend to grow without the rust, at least for a while. Organic fungicides can also help, as can avoiding watering the plants in the afternoon or evening.
Hemerocallis ‘Black Ambrosia’ with Miscanthus sinensis ‘Variegatus’ and Persicaria ‘Red Dragon’