True autumn crocuses have great charm

Press, 18 March 1988, Page 18

True autumn crocuses have great charm

Gardener's W DIARY

Derrick Rooney

i The colchicum family, as I wrote last week, is often erroneously referred to as the "autumn crocus,” but many gardeners, and particularly those with small city plots, might find more pleasure in growing the true autumn crocuses, a rather more interesting and diverse group of plants. I Except to the eye tuned in to fine botanical detail, one colchicum looks pretty much like another. The true autumn crocuses are diverse in size, shape ,hnd colour, ranging from pure white to almost pure blue. By careful selection bf species jyou can have them in flower from Febiruary to June. Yet jthey remain relatively uncommon in gardens. I imagine this is because a lot of gardeners have bees in their bonnets about | crocuses being spring j flowers. In fact, there j are about four autumn-flowering crocuses for every six spring ones; 'Europe alone has more than!2o autumn crocuses. ' ' i The I first of these are flowering now in my garden. Several clumps of C. pulchellus, have been out for more I than a week, and last Sunday I noticed a newly opened bud on C. speciosus? Both of these flower from bare ground and their leaves do not develop until much later. i C. pulchellus has pale j lilac flowers with prominj ent dark \ veins and an

orange ring around its yellow thrrat. The anthers are white, and this is one of the above-ground characters which differentiate it from C. speciosus; the latter has yellow anthers and a white throat but is otherwise similar. Either would do for most rock gardens, and if I had to choose I would give the nod to C. pulchellus because it multiplies more freely. Numerous other crocuses are in the wings, waiting to flower as the days shorten. The socalled "Spanish group” consists of C. serotinus, a portmanteau name for a once-large group now reduced to subspecies and varieties, including the very large-flowered salzmannii; and C. nudiflorus which is similar to C. speciosus floristically, but flowers later and is unusual among crocuses in being stoloniferous — its corms put out runners, on the ends of which new corms form, so that a single corm can colonise quite a wide area. C. salzmannii flowers in my garden in mid-April and is one of the best of the autumn crocuses — vigorous, free-flowering

and quick to multiply.. Unlike the (others, it never seeds in my garden. It has. I think, the largest corms of| all crocuses, up to scm across, and they, too, are | at least partly stoloniferous and as tough as old 'gardening boots; last year} sdme corms that I was growing in planter bags put out dropper roots, through the drainage, holep in the bag,(right through (the! bottom of the polystyrene} tray in which they wejre | standing; and into the I ground. j It is dangerous to generalise abqut plants" and their -distribution j but fairly safe,! I think, to say that the| leafless autumnal crocuses are plants of south-eastern Europe and .Western! Asia. The exception is p. jm edins, Iwhich comes from the Maritime Alps of France and! Italy. A white throat differentiates this from the (Greek C. cancellatus, which has a pale yellow thboat.C. banaticus, formerly more descrip lively known as C. iridiflorus, is distinctive in haying inner | petals much shorter thain the outer ones.!! The j outer petals tend!: to lie flat while t tie inner ones stand up, like I iris standards, thus emphasising the close relationship between crocusps and irises. C. kotschyanus was easier to pronounce and spell when it was} known as C. zonatus', but is no less worth growing! for the change of name. It has a pinkish lilac flower with

an orange-spotted inroat, and cream anthers and may well be the most common autumn crocus in gardens. A widespread and variable Western Asian species, it has five subspecies which differ only I in minor details. Probably it is the easiest crocus to recognise when dormant because jit has a very , wide, flattened corm with an irregular edge. The buds of this crocus start to expand in January, i but remain underground until April. Each year} it produces' a profusion . of tiny cormlets, Which form at the irregularities on the edge. Thus it multiplies rapidly. ( Of the autumnal crocuses which haye leaves at flowering tiirie (sometimes the leaves' are very small), a small group including the so-called "saffron crocus” has leaves with hairy margins (you may need a lens to pick this up). A larger group with smooth-edged leaves includes some choice species: C. Laevigatus,

whose variety, fontenayi, has corms shaped like tulip bulbs; and Cc. tournefortii, longiflorus, niveus, and caspius. Another member of this group, the pretty little C. ochroleucus, has small white flowers with a yellow throat and comes out later, in May or June, to carry on the crocus season until the first of the “spring” crocuses, C. irnperati, appears in midwinter. I ;

Despite its frail appearance and eccentric choice of flowering time, C. ochroleucus is remarkably resilient. Rain, snow, or frost barely marks its flowers.

C. laevigatus and C. longiflorus are desirable for the sweet scent of their flowers. C. niveus is a striking species; its large, pure white flowers have an orange throat and contrasting bright scarlet stigma, divided into three prominent branches. C. caspius is similar but its stigma is orange and unbranched.