Plum, gage, damson, bullace and cherry plum rootstocks
The range of rootstocks used for this group of closely related species is largely the same. Some varieties of can and were traditionally produced on their own roots. But this is no longer used and nearly all modern production involves use of rootstocks. A wide range of closely related Prunus species and more recently hybrids between Prunus species have been used as plum rootstocks. Original selections of plum rootstocks were also carried out at East Malling Research Station, UK and were mainly from Prunus domestica (plum), Prunus insititia (damson) and Prunus ceracifera (cherry plum or Myrobalan) species. The main rootstocks that emerged from this research and are in current usage were St Julien A and Brompton both are which are relatively vigorous. Like cherries dwarfing and semi-dwarfing plum and gage rootstocks are a relatively modern development. The first semi-dwarfing plum rootstock was Pixy developed at East Malling Research Station and released in the 1970’s. Although significantly less vigorous than its predecessors, Pixy proved to be of limited success as the fruit size and quality in the case of many varieties was not considered good enough for commercial production. Pixy is still used by some nurseries and we used it until recently when we replaced it with a better more dwarfing new rootstocks.
More recent development of plum rootstocks have mostly involved hybrid of various Prunus species. We currently use two such rootstocks VVA-1 which is a new dwarfing rootstock with which we have replaced Pixy, and Adaptabil which is semi-vigorous and we use as an alternative to St Julien A.
The rootstocks we currently use on a regular basis are VVA-1 (dwarfing), WAVIT (semi-dwarfing), Adaptabil (semi-vigorous), St Julien A (semi-vigorous) and Brompton (vigorous).