silverball:

I checked today and my outdoors Tomcot has red buds pushing. We are two months from frost free.

There isn't a good option outside of a greenhouse like mine. Never miss a crop in there.

The best thing I know of is evaporative cooling. Wet the tree every couple minutes whenever the temperature gets above 45F. Obviously this takes an automated sprinkler or misting system. Also well drained soil otherwise it may get too wet. This will delay bloom about two weeks if properly done.

The latest blooming apricots for me are Robada, Orangered, and Tardirouge.

This post was edited by fruitnut on Fri, Feb 15, 13 at 22:23

This info came from an email I received from Robert Purvis of NAFEX:

"Have I told you about the use of KDL (potassium dextrose-lactose) to prevent frost damage on fruit trees in bloom? This is an inexpensive and very practical solution to frost issues on fruit trees, berries, and vegetables. I have saved my apricot crops by spraying it hours before a frost occurred! An application will afford protection from frost for 10-14 days depending on how warm temperatures are during the period following frost."

Re: the KDL spray and other similar approaches, you might want to check out this thread:

http://forums2.gardenweb.com/forums/load/fruit/msg0110220230748.html

Fruit trees planted on the north side of a slope, or in the shadow of something, such as a house or an evergreen tree will flower a bit later, when frost is less likely. As the sun gets higher in the sky, they will get direct sun and break dormancy. I just planted a plum in this manner. It will have considerable winter shade, getting some good chill and staying dormant until after last frost, but plenty of summer sun. I live in L.A., so summer is like 9 months.

I've heard that people would shovel snow around trees which they wanted to delay bloom/growth in the spring. The idea was to create a large pile of snow/ice under the tree, which would then take a bit longer to melt, and would extend the tree's dormancy.

Never tried it myself, and not sure what you do if you don't have snow. But might be worth a try.

No snow here but I do so mimic it by wrapping the base of my trees with white sheets & draping the tops on really warm days. Sound silly but it buys me a week or more!

Gom that is brilliant- seems like it would work as well as naturally occurring shade which I have observed does create a microclimate that delays flowering.

You may delay the flowering with snow, but only a week or so and if the air temps are warm enough..even if the soil is still half frozen, the tree will start to blooming. Last year, due to the warmest March ever, I saw trees do this with frost still in the ground. They were on the north side of the house (soil was still shaded almost all day), but the tops of the trees were getting full sun and the air temps were almost summer like. The best (only?>) way to do it is by greenhouse or containers...and move them in and out of the elements. I've fruited full size white peaches last summer in a 15 gallon pot...so apricots should work fine.

The only scientifically proven method, to my knowledge, is evaporative cooling. There was a recent article in Good Fruit Grower, I believe, about trying it back East. It was proven in west Texas on peaches 30-40 years ago, two week delay in bloom. The OP is in SE Colorado which like west Texas has very low humidity in spring. It works better in that environment but will be pretty effective on a sunny day most anywhere.

In the non-fruit-growing world, the product "FreezePruf" does seem to have a lot of success behind it for providing a few degrees of protection during freezes, but it could be that it is not as effective on fruiting plants, and that it is just too expensive to be used on anything other than a very small scale (a gallon costs about $100!).

I want to thank everyone for the responses to my apricot question. The weather here has been so strange, with heat, then freeze, then heat again, none of the plants know what to do! we've got birds that don't belong here, humming birds with nothing to eat, more robbins than I've ever seen. I'm sure the goldfinches will show up soon - & they were never here at all until three years ago. well, like the chinese say for an insult, "May you have an interesting year"

I hear you about the weird weather. I think that if you were able to paint the trunk this would help without too much effort. From what I have heard the trees wake up from the bottom up, so if the trunk stays cool it will help. Obviously there is no other way to deal with this easily. Being at our altitude the sun can really beat down. It is much more intense than at lower elevations.

I am intrigued with the idea of evaporative cooling. Could you place some micro spay emitters in the tree and just turn them on when the weather gets warm? Here in dry Colorado swamp coolers do wonders so it would probably help more here than in a more humid environment.