Last year was my first year getting apricots that survived Spring frosts, and I used KDL once with temps of 28 during full bloom. I got fruit! but I’m still unsure if I used it properly. I followed the 3 oz KDL, 3 oz white vinegar to 1 gallon of water ratio and sprayed the tree the evening of the frost. From the article linked below, Bob writes “The tank mix should be sprayed lightly (not drenched) on the apricot trees the evening before a frost event is forecast.” It’s not entirely clear to me if that means the evening of the frost, or 24 hrs before the frost event.
Last year I sprayed when apricots were in full bloom, it looked like the spray caused some of the flowers to wilt and turn yellow/brown even before the frost. Maybe what I did was not a “light spray” though, I might be more of a drencher. When you spray KDL are you trying to get some on the flowers? Even though I ended up with fruit, I wasn’t sure if my application was helpful, harmful, or neutral. This year we had very warm temps in January and all our stone fruits look like they may be headed for a disastrous early bloom.
@rayrose do you have any feedback from your experience with it?
The only thing I would recommend is leaving some untreated check trees. to compare. I have used kdl and will this year as I still have product on hand, However, I would never purchase again as it has proved itself worthless for its intended use. I rank it about as effective as anti-aging pills or over the counter ed supplements.
It appears from Purvis this could be useful, but he does not define the term KDL.
What is KDL and how do you obtain it? I would like to know more about it since we will likely have many freezing nights during blossoming of peach and plums
Dennis
Kent, wa
Search agro-k on google. Under solutions- tree fruit you will find an article on the kdl. Under vigor= dextro lac products you can select kdl to find it is 0-0-24. You can find a dealer from the site or you can call the company as I did. Freight is expensive. Good luck and I hope it works for you as well as it seems to work for Purvis.
Given its definition, why not make it with coffee grinds? The dry coffee grounds contain significant amounts of potassium (11.7 g/kg) , nitrogen (2.8 g/kg), magnesium (1.9 g/kg), and phosphorus (1.8 g/kg). None of the other nutrients would be damaging to fruit blossoms. As a foliar spray it’s probably worth trying!
Dennis
KDL is potassium-dextrose-lactose from agro-K. I believe you need the lactose and dextrose sugars or the plant to uptake the potassium. So maybe you could DIY, but coffee is also not just potassium etc. It’s got all kinds of other things in it, like tannin, fat, etc that might not necessarily be helpful. But I do like the sound of a coffee spray.
I applied my first trial mixture of spent coffee grind tea on March 3, so far I see no signs of bad effects, my blossoms range from swelling to fully open:
My Mixture: 1 gal of coffee grind effluent, Two TBS of miracle grow all purpose fertilizer (has a number of trace minerals beneficial for blossom health) 1/2 gal skim milk (lactose), and 1/2 pint concord grape concentrate (dextrose). Several varieties were starting to open blossoms today. Applied it on one of our rare sunny days. The 10 day outlook here is still pretty warm with only tomorrow night forecast at 31F. That’s not low enough to affect blossoms, so I anticipate by next week the majority of my stonefruit will be vulnerable to any sudden freeze. So this should be a good opportunity to test a trial mixture. Next weekend I will do a follow on application since the advice is that you only get about a week’s protection from an application.
Update on my trial.
Per information from Bob Purvis’s data, “ Commercial apricot cultivars at full bloom can lose 10% of their blossoms after a half-hour exposed to 27F and 90% of their blossoms after a half-hour at 22F. For peach blossoms at stage 4, a 10% kill would be expected to occur at 25F, and for Prunes at 28F.”
On 3/3/24, a sunny day I made first application of frost protection on the blossoms and blossom swelling peach and plums
My trial Mixture: Two TBS of miracle grow all purpose fertilizer, 1/2 gal skim milk, and 1/2 pint grape concentrate. Several varies were starting to open blossoms today.
Since then we had had only one night of freezing down to 28F. I went around to check the blossoms that were at various stages of blossoming and found no evidence yet of deleterious effects of freezing or reactions to my spray mixture. Most of my peach blossoms were at stage 4, first pink which would survive naturally down to 25F before you could expect frost kill. So I have not yet had a freeze low enough to expect frost killing on peach or plums. Since the uptake of the spray takes only minutes on a sunny day, five days of observation seems to indicate no deleterious effects of my mixture. I plan to apply a second dose this weekend as more plums are coming into blossom stages, and the frost protection only last around 7-10 days per Purvis.
Dennis
Kent, Wa