Primulas for Long Season Colour

Primulas for Long Season Colour

by John Richmond

It's now mid August and the last of the year's primulas has just finished flowering. Purple flowered Primula capitata is the final plant in a sequence that ensured I have had a primula of some description in bloom in the garden since before last Christmas.

The year started with the commonest of the primulas. Most gardeners know - and grow - primroses and polyanthus. What's the difference? Primroses have one flower per stalk, polyanthus many. The yellow primrose, Primula vulgaris, grows wild in the woods and hedgerows round my home in Devon, England. In my garden both the wildling and its hybrid offspring, in shades of pink and red, seed around on my heavy, acid soil. I let them develop where they land and only remove those that threaten to swamp a smaller treasure. Amongst and under shrubs they can do little harm and I leave them alone. These are spring flowering plants, often in first bloom just after - or even before - Christmas, and building to a peak in March and April. They are beginning to colonise every scrap of spring bare earth - even if this is overgrown in summer.

Alongside these I grow a few selected primrose and polyanthus varieties. I'm building a small collection of double primroses, including white flowered 'Dawn Ansell', peach 'Sue Jervis', and red flowered 'Lillian Harvey'. I've grown, lost, and am growing again the old-fashioned gold laced polyanthus. The smaller statured Primula 'Wanda' varieties hang on from year to year and slowly increase in some of the shadier spots in the garden. The best of these have dark leaves to add to the colourful flowers. All of these, the wildlings and selected forms alike, take up little space, look delightful when interplanted with small spring bulbs, and provide enormous interest at a time when any colour is to be cherished.

Also for spring are two other favourites. Primula rosea is a moisture lover, small in stature, early to flower and, amongst so much bare earth, shocking in its vivid pink colouration. It slowly spreads with me but I've yet to find exactly the right site for this little beauty to really flourish. Far easier to please is Primula denticulata, the drumstick primula, which comes in a variety of colours, red, pink, lavender and white, with fat heads of typical primrose flowers crowded into a globe atop stout stems. This seems to be happy anywhere the common primrose thrives, building up stout clumps above which the tightly clustered balls of flowers are carried on stout stalks.

By May the winter and spring bloomers are virtually finished and it's time for some of the other species to take over. First of these are the 2 - 3ft / 60 - 90cm tall candelabra primulas. These arrange their primrose flowers in a series of whorls up the tall flower stems. 3 or 4 whorls are common but exceptionally strong plants can have up to seven, opening in sequence to give a long season of colour. Moisture lovers, they never look better than massed at the side of a pool or in drifts in a shady woodland glade. I can't provide the latter but I can provide the poolside. In the moist soil around my small pond I've used Primula japonica in shades of red and pink, and plants of the mixed 'Harlow Carr Hybrids' strain in shades of yellow, apricot and orange to give early summer colour in a combination with siberian irises. In time they should seed around to give a range of colours from which I can select the best. In the front garden P.japonica 'Postford White' is kept in isolation to prevent cross- pollination and ensure that any seedlings are also white.

As the candelabras are finishing so Primula vialli is developing. I've written about this red shingled beauty elsewhere but once again the moist area around the pool is housing a small group of seedlings. I treasure these plants, with their 18inch / 45cm tall flower spikes topped with red shingled buds that open to lavender flowers. Seed collection will soon begin - essential to maintain and increase the stock.

Primula florindae, the himalayan cowslip, was the next in the sequence to flower, starting in late June and finishing at the end of July. I've always admired this plant for it's foliage as much as its flowers, paddle shaped, dark green leaves that can reach 12 inch / 30cm in length and width. The citron yellow or red tinged flowers are also worth having, hanging bells on tall stalks that dance in the wind and give way to upright seed heads for autumn interest.

Which brings me back to Primula capitata. Heads of rich purple flowers, coated on the outside of the blooms and down the stem with mealy white farina, distinguish this easily grown primula. Like most of the family it too needs a moist soil, preferably on the heavy side and with a good deal of humus content. In return it repays with flowers that last well into August, by far the latest of all the hardy primulas, and nearly bridging the gap until the first flowers of the primroses start the sequence once again.

None of these are difficult to grow and increase. The candelabras, viallii and florindae all need constantly moist soils - but never waterlogged conditions. All the types appreciate some shade in the hottest part of the day and the type of climate where summer rain is regular and the air moist with cool humidity. Propogation for most is by late summer division as root growth resumes, ensuring the roots are spread out (never folded) when the offsets are replaced in new sites, and by seed, which needs light to germinate. You can collect this and surface sow on a pan of moist seed compost but even this may not be necessary. Given the right conditions many will grow like weeds, seeding freely around. That's when the problems begin. It takes a hard heart to cull such beauties - but at least your friends and fellow gardeners will benefit.

About the Author John Richmond is a keen gardener who lives and works in the South West of England. He has a scientific background as a professional ecologist. He has written occasional articles for gardening and other magazines in Britain since 1984, specializing in garden wildlife issues and hardy plants. Correspondence from other gardeners is always welcome.

About this Author