After seeing the lackluster flowering buds on my stone fruits this year, I was wondering if anyone knows if I whitewash the fruiting spurs if that increases chill hours and if it also delays bloom time?
2 Likes
I would imagine it does. I have considered painting my pots black for early spring kick-in-the roots and draping a white sheet around the pot for he summer.
2 Likes
It is not likely to help much. Time above a temperature range is what induces bud break, below that range counts as chill hours caveat that many trees do not recognize time below zero as chill hours. Between 45 and 60 degrees is the usual range most trees are sensitive to. Above 45-60 counts as heating hours to break buds. Below 45-60 counts as chill hours. As noted, several species do not appear to count below zero as chill hours, probably because freezing temps prevent metabolic changes in the mechanism for chilling.
Still would be worth a try. Sunlight on trees definitely heats the limbs. You might keep them just cool enough to avoid breaking buds into a spring frost.
2 Likes
Research by Bill Lipe with Texas A&M in Lubbock found that evaporative cooling was effective at delaying peach bloom. The protocol was to wet the tree every 5-10 minutes whenever the temperature was above 45F. It would also be effective at increasing chilling earlier in the fall/winter.
Whitewash/paint would have some of the same effects. And would have less negative effects. Spraying too much water can be detrimental depending on soil and weather conditions.
Lubbock isn’t south Texas and has lower humidity which aids evaporative cooling. But some of the same effects should carry over.
1 Like
We tried this experimentally in California where chill for Cherries is an almost annual problem and whitewashing if you can call it that by using kaolin (powdered clay) did not work.
Kaolin is often used on some fruit and nut trees to reduce sun burning and to try to reduce heat effects in midsummer on sweet cherry which causes doubling in developing blossoms and hence doubling in the front which is a defect for commercial purposes. It has good effects for these purposes but doesn’t improve the situation with lack of chill.
3 Likes
FRUIT NOT FRONT! Bad me for depending on voice entry without reading it.
1 Like
Thank you guys for your input! Maybe I’ll do my own experiment this winter and white wash alternating fruit spurs next year.
1 Like
If your tree is small enough you might try a shade screen.
2 Likes