Autumn-flowering bulbs need a summer of sleep. They hail from Mediterranean regions – places where the summers are hot and dry, and it makes sense to siesta. But by the time autumn returns, and with it the rain, they flash back into action, with delicate flowers arising from the earth long before their leaves. If you’ve not tried autumn bulbs before, colchicum, commonly known as naked ladies, are a good place to start because they are otherworldly and yet very easy to grow.
The large blooms of colchicum look mightily like those of an oversized crocus, but they are actually members of the lily family rather than the iris. Most produce their flowers from late summer to mid-autumn. Then, in the cool of early winter, they start to put out their large, strap-like leaves. These increase in size until May, at which point their seedheads ripen, to be released over summer. During these hotter months the leaves die back and the bulb seemingly disappears. But as the soil temperate drops, the flowers re-emerge.
Although colchicums like warm, dry soil, they do not like to bake, so they need to be insulated by a deep layer of soil
These flowers are quite extraordinary, but are fragile and easily damaged by wind, so they need to be situated somewhere sheltered, either in pots or protected corners of borders. They can also work well at the base of a hedge – such as a low box – as long as it gets good light. Or they can be planted on the sunny side of large shrubs, such as the Cotinus coggygria bush – the smoky purple leaves contrast wonderfully with the pink of the colchicum blooms.
Order colchicum bulbs in July, to be delivered and planted in August. Although they prefer warm, dry soil in summer, they do not like to bake, and so they need to be insulated by a deep layer of earth. Plant them at least twice as deep as the length of the corm (bulb). You don’t have to water them in when planting, nor do you need to wait until it has rained, as the plants are still dormant. But they do need to be in a spot that is moist when in growth, so make sure you haven’t planted them in rain shadow, particularly if they are beneath an evergreen. And don’t, however tempting, imagine you can remove the leaves in late spring while they are dying back, as they are crucial to corm fattening for autumn.
Colchicum speciosum is perhaps the most robust and easiest to get hold of. It can even be grown in thin grasslands, the sort under an orchard, for instance. The flowers are large and robust enough to take the competition of grass and are surprisingly weather-resistant. The pure white form, C. speciosum ‘Album’, is pristine and quite lovely. There are also a number of tessellated forms with extraordinary patterns on the flowers. ‘Conquest’ is one of the best, with bright lilac-rose tessellated petals. For a pure pink try ‘Pink Goblet’, which has flowers shaped and coloured just as the name suggests. Finally, the double-flowered ‘Waterlily’ is a beautiful amethyst-lilac. But rain and wind nearly always damage them, so perhaps best for a pot in a sheltered spot.
July 15, 2022 at 03:42PM Alys Fowler