[NAFEX] Pruning and Dormant Spray
dmnorton at royaloakfarmorchard.com
dmnorton at royaloakfarmorchard.com
Mon Feb 18 20:05:59 EST 2008
Your pruning on any apple trees should be done while the trees are in
complete dormancy. If you have stone fruit, prune them at green tip,
usually late March, or early April for Zone 5. Your dormant oil needs to be
done when day temperatures get above 45 degrees and freezing temps are not
expected for at least 24 to 48 hours. For apple trees your dormant oil can
be sprayed from dormancy up to green tip. You can never combine copper
sulfate alone with dormant oil, but your fungicide spray does not need to be
applied until green tip for apples and pink for stone fruit, so there should
be no conflict with the dormant oil and the fungicide if you do the dormant
oil prior to or at silver tip. We do all of our pruning (which began Feb.
4) and then do our dormant oil spray based on the 45 degree temp model at
silver tip. We follow with copper at green tip and our fungicides (captan)
at pink to bloom.
If you go to http://www.hort.purdue.edu/hort/ext/sfg/ you can download free
copies of the various spray guides for the Midwest that will give you all
the timing for the various sprays needed. Hope this helps!
Royal Oak Farm Orchard
----- Original Message -----
From: "William C. Garthright" <billg at inebraska.com>
To: "NAFEX List" <nafex at lists.ibiblio.org>
Sent: Monday, February 18, 2008 1:33 PM
Subject: [NAFEX] Pruning and Dormant Spray
>I hate to interrupt this discussion with a fruit question (that's just a
>little joke, I assure you), but...
> With last year's nasty April freeze in mind - and Nebraska's normally
> unpredictable weather - I'd like to delay breaking dormancy as much as
> possible this spring. So far, it's been a remarkably uniform winter, with
> some snow cover (not a lot) and below-normal temperatures almost all the
> time since the first of December. We usually have warm spells, but not
> this year. Of course, that can change at any time.
> I've read that both pruning and dormant oil spray encourage plants to
> break dormancy, earlier than they would otherwise. But I've also read that
> dormant spray can react with some fungicides, so you need to keep them
> separate by a couple of weeks (sulfur and captan, anyway). Last year (my
> first year at this), it seemed to make sense to prune first, and then
> spray with dormant oil, since the trees would be more open - and require
> much less spray - after pruning. This year, I'm struggling to reconcile
> all these different requirements. (Note that I have a big variety of
> different fruit trees, bushes, and vines, which just makes things harder.)
> Any recommendations? I've got awhile to go yet, but I want to be ready.
> How late can I wait on these things? And what order would you recommend? I
> need to prune and to spray with dormant oil, and I'd also thought to do a
> dormant spray of lime sulfur (apparently not within two weeks - either
> side - of the oil?). But if I want to do all of these as late as possible,
> is that going to work?
> I'd appreciate some advice. Last year, I pruned on March 7 and sprayed
> with dormant oil on March 8. That was too early, I believe. But then, we
> had a *very* warm March last year. Either way, I want to delay my plants
> from breaking dormancy - and blooming - as much as I can. At the very
> least, I don't want to do anything to speed it up.
> Thanks much,
> Lincoln, NE (zone 5)
> I'm learning real skills that I can apply throughout the rest of my life -
> procrastinating and rationalizing. - Bill Watterson's "Calvin and Hobbes"
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