Apple producers in our ideal growing environment have often felt bigger trees produce better results. However, with a globally competitive market and health conscious consumers becoming more aware of production techniques, dwarf apple trees in intensive systems can offer considerable benefits.
Higher establishment costs due to greater tree numbers, maybe 2-3 times as many as a conventional system, and the support structures to help bear the early fruiting, can be quickly offset by the ability to recover these costs sooner and give earlier returns. Many rootstocks and rootstock combinations have been and are being tried and tested in the region.
A Lower Moutere grower quick to see the advantages of the intensive system has been Peter Besier who has various varieties of 6 year old dwarfing trees planted. He recalls several years ago that "a well known pomologist in the Hawkes Bay, Dr McKenzie had been overseas and looked at the shape of orcharding in New Zealand and started to promote the central leader system as a better proposition, going away from the fast model and the four leader system. He introduced the first wave of more up-to-date fruit growing that was perhaps more manageable."
"In earlier days there was competition who had the strongest, loudest sprayer because we had to spray all these big trees."
"We've still got 'Pinetree' Meads mentality - big is beautiful, I don't necessarily believe in it. Our climate here is such that with our semi-intensive systems we are getting good production, however quantity is not the issue of the day it is quality."
"You're cutting your costs and can change your varieties much quicker " he said of intensive techniques. "The biggest handicap has been, and to a certain extent still, has been the availability of the dwarfing rootstocks."
Syd Lambert from Lambourne Marketing near Richmond believes, " it is clear that successful orchards of the future will be planted much more intensively than what has been planted in the past."
"Interstock and dwarfing trees are showing high fruit quality in fruit firmness and brix levels. Fruit size has been larger and is a real advantage for varieties such as Royal Gala."
MM106 with a M9 interstock is producing a dwarf tree and has seen as many as 1900 trees/hectare in a 3.5m x 1.5m situation.
M793 with a M9 interstock also produces the desired dwarfing qualities. This has seen as many as 1250 trees/hectare in a 4m x 2m situation and this combination has a resistance to phytophora and woolly apple aphid as well as being able to be used in a replant situation.
M26 produces a slightly larger tree than M9 and appears a good stock for vigorous varieties. These can be planted at 3.3m x 1.5m giving 2000 trees/hectare.
Tolerant of a replant situation, the M9 clones produce a dwarf tree that has been planted in densities from 1500-3000 trees/hectare.
Weed matting is another system that has been trialed in conjunction with M793 and MM106 on heavy and clay soils. By filling out the allotted space in the row and with the help of fortification, turning the vigour into fruit rather than growth, very high production levels can be achieved.
Production starts in year 2 with approximately 25 tonnes/hectare. Year 3 an increase to 80 tonnes/hectare and by year 5, 125 tonnes/hectare. Trees are planted at 3.3m x 1.5m giving 2000 trees/hectare.
Peter Besier believes you have to consider environmental factors as well, "the problems with spray drift and the change to more environmentally friendly ways of growing things are becoming prominent issues."
"I use a tunnel sprayer that goes right over the trees, I don't have drift, my spray bill has been cut in half. I also make a deliberate attempt not to let the trees go any higher than what can be reached with a little box and most of the trees are picked from the ground. And the production for me has certainly been very satisfactory. "
"If I had to make a choice again, I would definitely go with small trees, high density because I think it is the only way we are going to survive in the long run."
Mr Besier also acknowledges the ongoing contribution towards research into this system, of Dr John W. Palmer, at the HortResearch Nelson Research Centre in Motueka. "It needs a lot more detailed work and research in regard to which varieties are doing well. We are fortunate that we have John Palmer who has dealt with the M9 all his life, and he has had an enormous input in promoting the system and providing guidance."
