I have had apple trees for over 15 years but still do not know when to spray them with dormant oil and sulfur (a.k.a sulphur), In January, like now, it seems too cold. In a while it will get a bit warmer. But it will be raining incessantly. Useless to spray when it is going to rain in the very near future. Then the buds will be opening and it will be too late to spray. Every year I go out some weekend and say - 'Yay! the first non-freezing dry day in months, time to spray ... Oh No the buds are all opening". And I don't spray. Today it crosses my mind - maybe I can spray tomorrow? It will go to about 0 C overnight, and maybe to + 3 C during the day, and I will freeze my hand while I spray, but maybe the spray will be effective .. Will it?
Heloo Soccerdad! Wait until a warmish, sunny and preferably windless day in February! Or in January, if it should occur! This afternoon came very close to that!
Thanks. Here it was +3 and dense fog today which is not too close to warm and sunny by my standards, but I have gotten spoiled here in lotusland: my daughter in TO would regard +3 as balmy.
It was 14 celsius this afternoon, my yard faces SW... and the fog lifted in the am... If it was 18c. I would have sprayed today... but as I mentioned, wait for February. Colorado is in a lower temperature climatic zone than Metro Vancouver... and the freeze thaw range is prevalent well into their springtime...
seriously? wow, I was in Langley, cloverdale, delta, burnaby and New West today, didnt find any weather that felt like 14c, I need to reschedule my days!
I prefer to spray a delayed dormant spray, when the trees are just starting to push their buds (bud stage 3-5). Much more effective that way. Spraying now, or in February, may smother a few overwintering aphid or scale eggs, but not much else. If you wait, the sulfur in the spray will actually help suppress powdery mildew, and the oil will still do its smother job. At this stage, no danger of burning the emerging foliage. (This is the timing commercial orchardists now use). As for timing, this spray usually happens mid to late March for us.
There are micro climates in backyards, courtyards etc, it all depends on your exposure and the time of day...on the north side of the house, the temp was only 4 degrees c.
Ah, to live in the Land of Large Lots. I have a standard Vancouver west side 47 x 130 lot - which would today cost about 10 times my average annual earnings and which I could not, therefore, afford - which faces south, and my apple trees will be shaded by the house for some months to come. From my experience, it will never get anywhere near even + 10 C in January or February in my backyard. As I type, at 9:20 a.m. local time, the frost lies deep on every horizontal surface. But I will be on the North Shore at sea level at 2 pm for #4 daughter's soccer game and might bring a thermometer to see what it is like there. The idea of a delayed-acting dormant oil spray is interesting. I have always thought that the later one sprayed, the more effective the spray would be, but I have never heard of being able to spray after buds start to open; every garden store employee and every gardener has told me that this will kill the buds deader than a doornail. Silver Creek, do you have a link to something that will give me details?
This is one link to look at- http://www.cloudmountainfarm.com/pdf-guides/DiseasePestManagement.pdf. Another detailed resource is the Crop Protection Guide from WSU- http://cru.cahe.wsu.edu/CEPublications/eb0419/eb0419.pdf. That one is more Eastern WA centered, but the information applies on the west side too, as it usually refers to bud stage for timing, rather than time of year.
What are you spraying for, what are you trying to control? Scab is one of the important problems in this region. Fungicides would be used for that, except when you have planted scab immune cultivars. Winter and spring dormant sprays would be used for reasons other than attempting to prevent scab.
I have given up trying to control scab. I am hoping to reduce the bugs. Sorry for being so ignorant, but I do not know what bugs they are - maybe coddling moth - for I have never seen one, but most of my apples are destroyed each year even though I spray with bacillus (sp?). My Cox's Orange Pippen usually does well, for evidently its fruits do not start to develop until after the bugs lay their eggs, but my Empire and my Golden Delicious fruits are usually 90-100% bug-ridden. (My Elstar has so far done OK, and this year my Ambrosia should give me a decent crop so I will see how it does).
If you are trying to control codling moth or apple maggot, then a dormant or delayed dormant spray won't help. Control of these pests require summer sprays based on heat units. But you need to know exactly what you are trying to control, as the timing is different depending on the pest. (and scab is fairly easy to control, but timing is crucial- see the two links previously posted). Codling moth damage is a single hole, going through the fruit and often exiting through the core stem or blossom end. Apple maggot damage is riddling throughout the fruit.
It seems that I generally get apple maggots but that later in the season I get coddling moths. I would rather have pests than non-organic sprays though.
I use organic sprays (spinosad for codling moth, luckily I don't have apple maggot, yet, but spinosad also works for that, timing is different). For just a few trees (I have 70), I would use footies. Slip dime sized young fruit into the toe of the footie, wrap the rest around the stem. The apple expands into the nylon, apple maggot flies and codling moths can't lay eggs on it. Perfect fruit. Here is one article from the Home Orchard Society- http://www.homeorchardsociety.org/article/47/. The Seattle Fruit Tree Society also promotes these, and they are available through these societies and through some fruit tree mail order stores.
