Results of experimental plantings and demonstration plots in 2019 and 2020

Results of experimental plantings and demonstration plots in 2019 and 2020

In 2019, three experimental plantings and demonstration plots were assessed and recorded.

Performance of Victoria on four different rootstocks

The experimental planting comprises four replicated 5-tree plots of Victoria on the following four rootstocks of varying vigour:

• VVA1
• Wageningen
• Wavit
• St. Julian A

The planting allows replicated comparisons of the performance of Victoria including:

• Tree size/vigour
• Flowering time
• Ripening time/season
• Disease susceptibility
• Productivity
• Fruit size and quality

Replicated demonstration plots of Victoria planted on four different rootstocks with four different tree architecture systems

The experimental planting established in 2016 comprises two replicated plots of 16 rootstock/tree architecture combinations. The rootstocks and training systems used are:

VVA1                                  Narrow A-frame

Pixy                                     Narrow table-top

Wavit                                   Super spindle

St Julien A                          S system

Replicated comparison of the two new East Malling varieties P6-19 and P7-38 on Wavit versus St. Julien A rootstock

The experimental planting (planted spring 2017) comprises four replicate 6-tree plots of each of the variety/rootstock combinations.

Key results in 2019

Yields

• The Oblique and Super Spindle systems on the dwarfing rootstock VVA1 produced the highest yields in 2019.

• The Narrow Table-Top and Super Spindle systems on Wavit rootstock also performed well.

• Over the past three years, the Super Spindle has produced the highest yields.

Gross margins

• The average gross margin for UK plums has been estimated at £250/ha/year.

• Other tree fruit crops make considerably more.

• The Oblique and Super Spindle systems on VVA1 rootstock and the Narrow Table-Top on Wavit have produced a higher gross margin in 2019 than an average cherry crop.

Fruit quality

• The training system x rootstock combination appears to have an impact on fruit quality.

• Information needs to be gathered over several seasons before any firm conclusions can be drawn, but information will be presented every year on this website.

Key results in 2020

Yields

• The Oblique Spindle on VVA1 rootstock produced the highest yields in 2020.

• Second highest yields in 2020 were recorded on the Narrow A Frame training system on Wavit rootstock.

Fruit quality

• Between the training systems or rootstocks in 2020, there were no significant differences in Brix levels or fruit size.

• Highest firmness and individual fruit weight were recorded on the Candelabra and Fan training systems and Wavit and St. Julian A rootstocks

Drawing conclusions so far

At this stage in the Centre’s life, it is still too early to draw firm conclusions, but the trends are showing favourable results for VVA1 and Wavit rootstocks and the Super Spindle and Oblique Spindle training systems. The performance of these demonstration plantings will be assessed and recorded again in 2021, although at the time of writing, some flowers have been damaged by frost and yields are likely to be affected.

It is also worth noting that a proportion of trees planted on the VVA1 have died from canker whilst a proportion of the trees on Wageningen rootstocks did not establish well. These trees are being replaced.