We know that this has been a difficult season. Apricot crops for main stream varieties are really light, and some cherry blocks have been walked away from as there was insufficient fruit to put pickers in. Plum loads are variable and while peach and nectarine are generally Ok that is not always the situation.
Would having the trees in a covered cropping situation have made a difference, leaving aside the cost of construction of the houses?
This season the weather has given us; normal winter chilling (but a late start to accumulation), hail events, (4 or so that I have heard of), inclement weather during much of pollination (hence the light crop loads), more rain than desired in both volume and events, and low growing degree day accumulation.
While a permanent or removable cover may exasperate the winter chilling effect all the other weather factors would be mitigated. In addition, there would be less disease protection needed and with some stonefruit growers now applying few if any insecticides that situation may not change, or it might. We would need to think more carefully about pollination inside structures, but that work is already underway. Less water might be needed especially during windy periods, and the amount of time to spray trees increases as its calmer for longer.
The recent FOPS field walk, especially the Rockit block in Stock Road, was a fine example of that system done very well. What I appreciated was the measured way in which the trees were grown, so that upon reaching the top wire the vigour was under control with crop load and other techniques as required. Contrast this with the head long rush to fill the canopy approach and the then difficulty of managing the tops. So, whether it’s a FOPS or UFO system or something like the pergola as espoused by Ronald Vermeulen’s intensive pergola (think kiwifruit) canopies under cover has a certain appeal when matched with this type of system.
The cost of a fully covered system might necessitate highly productive new IP varieties, with a good information background and of course dwarfing rootstocks. I have seen enough of Gisela 5 and 12 now to think that they are well worth a try for cherries. Andy McGrath has some new dwarfing stocks at various import and testing stages so this field should progress. If we can take cherry production from the 7-15 t/ha to a regular 20 tonnes and then march up from there, as well as guarantee buyers that the product will arrive then that might be what we call future proofing.
There was a bunch of rootstocks imported a few years ago for the other stonefruit crops and some of these can still be found as trees. Should there be interest and some commitment a revisiting of what’s still possible can be done. Shifting these crops from 20-30 t/ha to 40’s and 50’s under covers to a waiting market seems like a fine goal to ponder over the few days off over Christmas and New Year.
A very quick google search showed two websites, www.tupu.nz and www.eeca.govt.nz that are already talking about covered crops and the benefits, including using less carbon. There might even be some funding available for early adopters.
Thanks for the opportunity to indulge in a wee rant. I trust you will get a day or two to spend with family. I also hope that the rain will ease up shortly, the sun will shine and we can have a Hawkes Bay summer. We have visitors from France and England arriving soon and I will get a lot of stick should the sun not come out very soon.
Merry Christmas
Richard Mills
Summerfruit Technical Advisor
021 632559