February and March were wet with something like 300%, or three times, normal rainfall. April, May and June were relatively dry with about half of what might be expected. Our big accumulation months of July and August had half again compared to normal, or 150%. I’ll come back to this later. This is good time to have really good drainage – a fiddle around the edge? Personally, I’m seeing standing water where I have not before. No wonder sprayers are making a mess.
Winter chilling was the lowest that it has been in the last five years. Comparing this winter just gone with 2018, which had good amounts of accumulation we are missing about 20% of the units. Looking at the numbers in a different way, June, July and August were all about 1.5°C warmer, in a comparison with the last 18 years. A bit less of an increase near the coast and a bit more dramatic in our more inland growing areas. Yet flowers of apricots, nectarines, peaches and plums seems to be of good quality and in sufficient numbers. That would indicate that was sufficient winter chilling even with reduced accumulation. Cherries are still waking up, and do require more chilling so we shall see what happens. Cherry responds well to dormancy enhancing products should these become more necessary with continuing warm winters. So at least for this part of the climate matrix we do have a fiddle to apply.
That frost was a doozy! Not hugely deep but long, with some starting protection at 8:30pm. There are reports of -3.5°C but mostly in the -2°C area. Without frost protection fruitlets are absolutely smoked and there will be losses, but there are no wide-spread loss reports. All that rain was perhaps the saviour as the wet soils prevented the situation from being so much worse. Any damage will be well visible by now. A bit more than a fiddle with water, wind machines and helicopters used, but the crop, in large part was saved.
Back to water again, and what might be the unknown at this stage, and perhaps the major influence for the season. The obvious is getting cover sprays on for brown rot and botrytis control. A warm day at full bloom might be good enough for pollination and then we wait to see what happens with fruit set. As Ronald Vermeulen said at the recent field days, it’s the stresses at pollination and post-pollination that influence set. Too much or too little of a critical input can trigger fruit drop.
With good drainage, enough of the root hairs will be strong enough to support the fruit that has been pollinated, sprayed, frost protected and sufficiently chilled to carry a crop. Maybe the stressors that we are encountering will set a crop close to ideal. We shall see.
Now let’s see how the cherries and apples go!
Summerfruit Technical Advisor