by Alan Titchmarsh
When you want a conservatory full of colour all summer, plant exotic bulbs, and grow a spectacular display for a song.
Exotic bulbs (and other plants with storage organs such as corms, tubers and rhizomes) are a particularly seductive group. By growing them from scratch at the start of the growing season, you can have an unusual or downright rare plant for a good deal less than the price of an everyday conservatory plant bought in full flower.
You’ll enjoy it all summer, then at the end of the season you still have the bulb (corm or tuber) to grow again the following year. And with no bother. It’s a great investment.
Some of the very trendiest bulbous conservatory plants right now are new, non-hardy forms of Zantedeschia, sometimes called calla lilies. They have large vase-shaped flowers, almost the size of your clenched fist, but in amazing colours – gingery-yellow, blush-pink, purplish-black, and rosy-scarlet. The foliage is equally dramatic; large arrowhead-shaped leaves dappled with white flecks, dot and spots, and the plant makes a good five- or six-inch potful, standing roughly 15 – 18 inches tall.
They could be stood outside in summer, given a sheltered spot that’s protected from strong sun, but unless summer is a real scorcher they do far better in a conservatory.
For a really showy ‘oddity’, look out for scadoxus. Scadoxus multiflorus (blood lily), flowers in July or August with a football-sized sphere of long coral-red stamens growing at the top of a bare straight stem, before any leaves appear. Plant each bulb individually in a five or six inch pot and don’t disturb until it really must be repotted.
Two close relatives also turn up occasionally in catalogues; Scadoxus puniceus is similar but with bright orange flowers, and Haemanthus albiflos the shaving brush plant, has large, white, bristly shaving-brush-shaped flowers with yellow anthers at the tips of the stamens – it flowers rather later, October-ish, and flowers at the same time as it’s in leaf. All three grow around a foot tall.
But one of the longest-flowering summer bulbs is an old Victorian favourite, Achimenes, the hot water plant. The individual plants are small, so for maximum effect grow five or ten of the tiny tubercles in a six-inch half-pot. The resulting dense bushy plant looks something like a more exotic busy Lizzie, growing roughly six inches tall with small, toothed, oval leaves and a mass of five-petalled flowers on long tubes growing out from the leaf joints along the stems.
There’s a good range of colours, from white to purplish blue, red, lavender and yellow and some have quite strongly patterned throats, which makes them look almost orchid-like. It’s easy to house a small collection of hot water plants on a shelf or shady windowsill, since they dislike direct sunlight.
While some unusual bulbs are decidedly tricky, the ones I’ve mentioned here are all easy to grow. Start them off any time over the next few weeks on a warm windowsill indoors, in pots of half-and-half John Innes No.2 and multipurpose compost, water sparingly, and move them out to the conservatory after the last frosts are past, for a blooming good show on a budget. You won’t regret it; they are rarely if ever available to buy as growing plants in the shops.