Wednesday, 22 August 2012


by Hilary Rowley

I measured 100mm of rain in my rain gauge for last week (Orokonui); that's ridiculously wet. The Orokonui Road riverside orchard planting got very wet, but didn't flood luckily.  All this dampness is prime breeding for fungal diseases, which is why this area is so borderline for any fruit trees affected by leaf curl. I had always thought it was OK to spray at this time of year with copper oxychloride, which is counted as organic, as long as it is not overused, but in the world of biodynamics it is not OK, because it kills the soil micro-organisms, which  are a vital part of the soil health system.

I have been doing some reading and listening, and it seems there is no perfect answer.  My bets are on spraying the fruit trees now with a solution of seaweed.  One recipe I saw was for 1 cup of molasses, 1 cup of seaweed powder, and 1 cup of milk powder (milk can be used to spray roses for fungal diseases), dissolve in 1 gallon of water and use as a spray. I am guessing that the molasses will make it stick.  Other possible sprays are:
  • a mixture of baking soda, soap, cooking oil and water... well I suppose it might manage to coat the tree;
  • or how about spraying 1 tablespoon of cider vinegar mixed with a gallon of water -- oh hang on, that one is acidic, and the previous one is alkaline; 
  • another is to use 1 cup of chamomile flowers to a litre of water as a spray.
I have not tested any of these sprays, so it is all very experimental.  I am just going to use a seaweed solution regularly, as I am not sure how to make it stick, and last longer.  Another method is don't plant peaches and nectarines, or plant strong varieties. Our Blackboy peach is thriving, while the more modern varieties are struggling with leaf curl.  I think, though, that you are better off with a living tree as they are expensive to buy, so spray with copper until you have the problem in hand, then be really vigilant with the superduper organic methods after that, and be really tidy and burn all your prunings, and even rake up the diseased leaves -- oh, and did I mention mulch? Comfrey is apparently good, and I think seaweed is amazing around fruit trees.

As for pruning, it is not yet too late to prune, it can be done right through until late September. At least that way you can see what is alive and what is dead.  Pruning later also reduces the chance of diseases getting into the cuts, which may be because they heal faster, and theoretically it is not so damp (ha ha).  It is also a good time for planting fruit trees, though WOO is not doing that this year, as we already have enough fruit trees to take care of.
I know it all seems like such a lot of work to look after fruit trees, but they do reward us so generously.  Bite into a deliciously sweet, crisp, juicy apple you have grown yourself, and it will all be worthwhile.

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