Posted on 27.02.2017 |
Added in Plant of the Month
Erythronium
 E. tuolumnense |
 E.albidum |
It is a sure sign that spring has settled in once the ‘Galanthophiles’ and ‘Croconuts’ have had their fix and quietly, another group of plants, perhaps one for the more discerning gardener, start to make their presence known in the woodlands. Erythronium is a genus of spring flowering bulbous perennials known commonly as ‘dog-tooth violets’ due to the shape of their bulbs, which have been described as reminiscent of canine fangs. They sit alongside other beauties such as Fritillaria, Lilium, Tulipa and Cardiocrinum in the Liliaceaea family. The Erythronium genus is made up of 29 species originating across Europe, North America and Asia. Growing Erythroniums can be very satisfying as they generally require little attention but will put on a guaranteed show each year, livening up the dullest of spring days with their shades and combinations of mainly whites, pinks and yellows.
If growing the straight species Erythroniums, it is important to consider their natural habitat and partially try to replicate it. They fall into two ecological groups, the first (of which the majority of those in cultivation are) tend to be found in deciduous woodland or at the edges of coniferous forests at elevations from 50-1700m. Therefore within a garden setting, grow in semi-shade under deciduous trees in deep loamy soil with a humus rich top, which can be created by seasonally mulching with leaf mould or garden compost in autumn (they are generally not too fussy about pH). They need a plentiful water supply whilst in active growth but prefer to be on the drier side in summer, so be careful not to overwater. The bulbs have the ability to pull themselves down to the correct depth and in dry years will be much deeper than you would expect. They can also be planted in thin turf where given time will naturalise.
The second group is generally found at higher elevations of 1500-3200m, often growing on the edges of woodlands, amongst scrub or out in the open- especially on north facing slopes, here they tend to have a very short growing season, emerging only a few weeks after the snow melts. These tend to be more sensitive and specific growers and less likely to grow as well as group 1 in cultivation.
 E. hendersonii |
 E. californicum ‘White Beauty’ |
While species such as E. hendersonii and E. oregonum make delicate additions to a shady border, many more of the hybrids and cultivars are readily available from nursery trade and are very worthy of consideration due to their vigour and selected forms. Cultivars such as E. californicum ‘White Beauty’ produces creamy white petals with warm, earthy markings at its throat and E. ‘Jeannine’ displays yellow flowers with red markings. With only a short growing season in the garden, the range of Erythronium emerge from February to April, then flower, set seed and die down again in late June.
 E. californicum ‘White Beauty’ naturalised |
 E. ‘Jeannine’ |
Many of the Erythronium species will multiply themselves vegetatively (for example, through producing small bulbils) and can form good sized clumps in just a few years, these clumps can be divided and planted elsewhere or left to produce naturalistic looking displays. By removing the old flowers as they go over, you will prevent seed formation and help speed up the multiplying of bulbs if you are looking to bulk up quickly, or to divide and share. However be aware, that some species such as E. oregonum can only be propagated from seed, in this case collect the seed once you see the seed pod beginning to split, then dry and store the seed until early autumn. If sowing in autumn, you need to sow outdoors in deep pots, the seed sown on the surface of a well drained compost with a 1cm layer of fine grit on top. Alternatively seeds can be sown in spring if the collected seed is placed in a sealed plastic bag full of moist perlite, in the fridge, 3 months prior to being sown.
Generally Erythronium grow without much bother from pest and disease, but you might get the odd slug and aphid attack. As the plants die down to the ground each year, most pest problems will keep themselves in check.
There are two national collection holders, one is RV Roger Limited nursery in Yorkshire (YO18 7JW) and the other is Greencombe Garden Trust in Somerset (TA24 8NU). The Royal Botanic Gardens, Kew, The Royal Botanic Garden, Edinburgh and RHS Wisley also hold good collections and a monograph ‘The genus Erythronium’ by Chris Clennett, published by Kew, 2014 is worth a read for further information on specific species information.
