Hi, I’m Ian, a horticulturist in Wisley’s Trials Department. Recently, with the help of garden volunteer Dennis, I’ve been tidying up the euphorbia trial in readiness for our Euphorbia Study Day on 26 March.
With striking flowers, amazing textural foliage and an architectural structure, euphorbias make excellent garden plants. Here on Wisley’s Trials Field, the RHS Herbaceous Plant Committee is assessing 94 euphorbias for the Society’s Award of Garden Merit, with flowering quality, hardiness and pest and disease resistance part of the assessment criteria.
Dennis deadheading. Euphorbia rigida
Those plants looking good right now include: Euphorbia characias subsp. wulfenii ‘Shorty’, with its abundance of beautiful yellow flower heads; the unusual evergreen Euphorbia x pasteurii (whose flowers will smell of honey later in the year); Euphorbia rigida, with its stems of spiralling leaves; and the scarlet-stemmed herbaceous Euphorbia sikkimensis ‘Crug Contrast’, which looks great as it emerges from winter slumber.
Euphorbia characias subsp. wulfenii ‘Shorty’
Not only extremely decorative, euphorbias have the bonus of being easy plants to grow, relatively free of pests and diseases, happy in most soil types and requiring little maintenance (although some require supports). Routine maintenance consists mainly of removing spent flower stalks from evergreens types and last season’s foliage and flowers from herbaceous ones.
Euphorbia sikkimensis ‘Crug Contrast’ & Euphorbia x pasteurii
One point to note is that all parts of euphorbias are toxic if ingested and the milky sap can be an irritant to skin and eyes. It is advisable to wear gloves, safety glasses, long-sleeved tops and trousers (as opposed to shorts) when deadheading and pruning them.
Do come along to our Euphorbia Study Day, where amateur gardeners and experts alike can view the euphorbia trial and hear from Euphorbia National Collection Holders Tim Walker and Don Witton and RHS Herbaceous Plant Committee members Bob Brown and John Fielding.