Bloom time depends on various factors like where you live, including your local microclimate, as well as the particular variety of apple that you have, how much water and sun the tree gets, etc. That being said, here in Wisconsin, you can expect your apple trees to bloom sometime in late May, plus or minus a few weeks.

You did not say that your apples bloomed or set fruit this year. If they didn't, I'm not surprised at all, because of the very unusual weather we had in March and April this year -- very warm followed by very cold. A lot of fruit crops nationwide are suffering this year as a result -- the blooms either died, or failed to develop, or had no bees to pollinate them. I have three young trees and I have a grand total of 3 apples. Three years after planting, I expected a reasonable crop this year, but the strange weather, in addition to my regular pruning, prevented much blossom at all this year. I think next year will be a huge crop nationwide, assuming the weather plays nice next spring.

As for spraying, I honestly have no experience, and I am trying to grow my apples as organically as possible. However based on everything I have read, there are various sprays that can be applied for all different purposes, but the ones for bugs and beetles often seem to be applied either immediately prior to bloom, or just after bloom when all the petals fall off and before the apples get beyond about marble size. So those one or two points in spring at bloom time might honestly be good enough for what I've experienced here in Wisconsin. I had some woolly aphids this spring and I was able to squish them all by hand since my trees are dwarfs and still fairly small (6 to 8 feet high). Other than that, I had some fly speck (I think that's what it's called!?) that killed one apple, but I haven't had any trouble with my other apples yet. You can spray maybe once or twice more in summer, but as it gets closer to harvest time, well, I guess I really don't know if it will be necessary. One thing I do not doubt -- some people will say you definitely need to spray, and some people will say you definitely do NOT need to. So do a bit of research on the interwebs or whatever, and then do whatever you think is best for what you want to get out of your harvest.

Best of luck to you -- if not this year, then in 2013!