The Annual Report: Easy on the eye, easy on the pocket
All gardeners have heard of annuals, biennials and perennials: If pressed, they will tell you that annuals are plants that bloom only once, and will need to be re-planted or re-sown the following year. Biennials, on the other hand, generally flower the year after they have been installed and then give up the ghost, while perennials, in the right conditions, will come back year after year.
If the distinction is sometimes blurred in a tropical garden, it is because many flowering plants here do not die back completely because the temperature never drops low enough to kill them off. For example, pelargoniums (geraniums), which in Europe are generally grown as annuals because they will not survive winter frosts without protection, enjoy an extended lifecycle in the subtropics and tropics. Nonetheless, general rules of thumb do apply, and most annuals in your Phuket garden will flower for only one season. So why bother with them? After all, shrubs will go on year after year, often with minimal maintenance.
There are plenty of good reasons. Annuals provide a brilliant range of colours, bloom more-or-less continuously during their solitary season, often possess both single and double forms, and generally flower at a manageable height where their striking hues can be fully appreciated. Add to these virtues their easy cultivation and easy availability as packeted seed, and you have an irresistible case for growing them.
Annuals with a low habit include petunias, impatiens (busy Lizzies), alyssum, gazanias, gerberas, portulacas, pansies and lobelias. Taller plants include rudbeckias (black-eyed Susans), larkspurs, statice and cosmos daisies. Six-footers include sunflowers and hollyhocks. They are normally seen at the back of borders or ranged along a wall.
Personal favourites, because they invariably grow well in Phuket, are African marigolds (tagetes) and gomphrenas, a pretty and good-natured annual that thrives in both containers and in open ground. As with the best annuals, gomphrena globosa, also known as bachelor’s button, produces its globular, tightly-packed flowers continuously, especially if you deadhead the old bracts.The standard colour is deep magenta, but there is also a russet-red cultivar which can be readily propagated from packeted seed. Since it hails from Central America, it is perfectly at home in a Thai garden.
It would be instructive to hear from readers of this column about gerberas. A spectacular member of the sunflower family, this tender annual can be found in containers in some garden centres, but less often in actual gardens. It is one of the most dazzling of all the daisies, with large flowers – pink, white, red or yellow – that may be as much as 12cm across, and with a striking centre that consists of hundreds of tightly packed florets. Sometimes this centre, or capitulum, is a contrasting black. Gerberas require full sun, mildly acidic soil for preference and regular watering in the dry season.
Although they belong to the same family of asteraceae, African marigolds are much less fussy about conditions. Moreover, tagetes erecta has a happy tendency to self-seed, so last year’s crop often reappears, phoenix-like, in the form of seedlings. The large, densely petalled heads are usually chrome yellow or deep orange in colour, and are often used to provide a vivid border for flower beds. They are also one of the most popular components in garlands and leis.
The smaller French marigold has a neater habit and russet red flowers often tipped with yellow. Both have attractive, ferny leaves and both are said to deter certain root-eating critters such as nematodes. When crushed, the leaves exude a pleasant, musky odour. Packets of seeds are widely available, but you may be able to beg, borrow or steal some from a fellow gardener.
The zinnia is another annual that does well in Thailand. While it can grow in temperate climes – I used to cultivate them in England – it originates from Mexico and, like the other members of the aster family already alluded to, prefers the sunny climate of Thailand.
Zinnia elegans is one of the most colourful of plants. Apart from the varied shape of its blooms which range from densely petalled dome to daisylike, the zinnia has a palette of colours matched by perhaps no other flower: white, yellow, pumpkin, orange, red, purple, lavender and even green. The flowers appear, characteristically, as single dramatic blooms at the end of long, hairy-leaved stems, and are much loved by butterflies. Some gardeners grow them expressly to encourage lepidoptera.
But they are a striking flower in their own right, easy to grow from seed, happy in a container, and, like African marigolds, apt to reappear as seedlings in the following year. Two observations: Though they grow in the wild in Central America, they appreciate a moist, humus-rich soil and plenty of sun. Otherwise they will be stunted and produce small flowers. Second, do not expect the re-seeded versions exactly to replicate the colours of their parents. They won’t oblige.
Patrick Campbell’s book ‘The Tropic Gardener’, described in one Bangkok review as the best book on Thai gardening for 50 years, is available for B500 (half price) to personal callers from 59/84 Soi Saiyuan 13 in Rawai (Tel: 076-613227 or 085-7827551).