As indispensable plants for seaside gardens go, ostespermums are high on the list, and most certainly in the top ten. They are low-growing, sun-loving sub-shrubs which produce a profusion of large, daisy-like flowers in spring. Modern varieties continue to bloom throughout the summer and autumn, but lack the poise and elegance of plain old Osteospermum jucundum AGM, a plant which my grandmother used to grow on top of her hedges. These carried white-petalled flowers, plum on the reverse, high above a dense cushion of green foliage.
At this time of year osteospermums can be picked up for a song in garden centres and florists. Colours range from white through pink, purple, yellow, orange and copper to burgundy red, but there are no pure reds or blues. Planted out immediately they make great companions for tulips. However, be warned, they are often treated in the nursery with a growth inhibitor to keep them short and neat in their pots. This means that they tend to sit looking rather sulky after the first flush of flowers is over, before springing back into action. Deadheading isn’t necessary, as modern osteospermums tend not to set seed. I do remove spent flowers, purely to keep the plants looking chipper.
Osteospermums like warmth and sun, although they will tolerate poor soil, salt-winds and drought. After a dry spell it may take a while for flowering to resume, and over-wetting can prove fatal. Osteospermums perform brilliantly in pots and on dry slopes where little else will prosper. Here in Broadstairs they form vast swathes on the seafront in abandoned Victorian rockeries, surviving both neglect and the dubious attentions of the council maintenance people. Although they are technically tender, in seaside locations they will often shrug off adverse winter weather. I have never lost an osteospermum to cold, only overwatering. If you wish to multiply a particularly desirable plant (I have a copper-coloured variety which seems to blend with all the colours I like in my garden) then softwood and semi-hardwood cuttings are a breeze to root, quickly producing bushy plants if pinched out regularly. Overgrown plants can be cut back hard after flowering and will reshoot nicely.
Although not the height of sophistication or originality, osteospermums are inexpensive, readily available, tolerant of neglect, bright and cheerful. If you live by the coast, or anywhere warm and dry, then few plants are as colourful and rewarding so early in the season.