The vast array of trials held at the RHS Garden at Wisley is impressive in itself. But the RHS also participates in another trial, a pan-European trial to find the best new annual flowers.
Fleuroselect has trial gardens in about thirty places across Europe in a wide range of climates and soil conditions. And one is at Wisley, not in the garden but at Deers Farm in Wisley village, the site of some of the Society's trials of shrubs and climbers. Deers Farm is only open on special open days, so look out for the opportunity to visit.
In the Fleuroselect trial, new varieties are grown anonymously alongside the most similar existing variety and inspected by expert judges regularly through the growing season. The highest award is the Gold Medal and one interesting stipulation is that all Gold Medal winners must be made available to all other members of the Fleuroselect organisation - so Gold Medal winners have the potential quickly to become widely available from a range of suppliers.
So what are the winners for this year, which did well both at the Wisley trial site and across Europe? There are three.
Sanvitalia speciosa 'Million Suns' (top, click to enlarge) combines three valuable features: it's colourful, compact and prolific. Ideal at the edge of containers or as neat ground cover at the front of a sunny border, 'Million Suns' needs little maintenance, rarely suffers from pests and diseases and will flower from May until the frosts. It branches well from the base and thrives in any sunny place in fertile soil that is not too soggy.
Also winning a Gold Medal for this year is Physostegia virginiana 'Crystal Peak White' (right). This is a white flowered, seed-raised version of the familiar Obedient Plant with upright spikes densely packed with white flowers. The flowers drop off as they fade so there's no distraction from the clean look of the remaining flowers. Sow early, the plants will flower well in their first summer. Use them in containers in their first season, then move plants to the border in the autumn.
Finally, perhaps the star of them all, Gaillardia x grandiflora 'Mesa Yellow'. Brilliant yellow daisies, huge numbers of flowers, superb in containers and a good perennial for sunny situations as well. ‘Mesa Yellow' is unusually hardy and tolerant of a variety of climates, it's especially drought-tolerant.
All three of these fine varieties are becoming available from seed companies this year. And they've proven themselves both at Wisley and around Europe.