Commercial orchards and other growers succeed because they take a systematic approach to disease control and pest pressure. And it can be huge expense that some growers aren't willing to make especially with tree fruit. Plus it could also be very time consuming depending on the size of the operation.
Smaller bush fruit can sometimes be less demanding depending on local growing conditions. Organic no spray/low spray fruit production is okay especially for private production I'm certainly in favor of it. But if your looking to profit from your endeavors it might make marketing products difficult depending on peoples expectations.
My boss..."Hey I have a sore throat from eating all this fresh fruit". Me..."No Boss that's just from all the pesticide." :confused2:
Along with access to chemicals not generally available without a pesticide applicators license the use of specialized equipment helps considerably, such blast sprayers where a thick leaf canopy is difficult to penetrate.
Much of it is preemptive too starting in the earliest parts of the growing season. It's an on going battle for the most part (not if problems are going to come but when) and usually by the time a casual observer notices any problem it is sometimes hard to eradicate and the best you can hope for is to keep it in check at that point (think tomato blight...you don't spray ahead of time and then boom one day its there and usually only gets worse

)
Warmer temperatures can certainly exacerbate disease problems as does dampness...rains and/or high humidity. The Northeast growers often experience increase disease problems with those conditions.
I watch too many growers/budding farmers learn stuff the hard way, like it aint hard enough already. :laughing:
but then of course experience can be the best teacher (however costly that may be)
Truly some of best you things can do is to utilize all the experience that extension agents and university research programs can provide. And avail yourself to industry oriented publications that relate to what your doing or want to do.
Here is the link to Virginia Tech's latest online commercial spray bulletin
2015 Spray Bulletin for Commercial Tree Fruit Growers | Publications and Educational Resources | Virginia Tech
I was going to recommend this link earlier in this thread
Growing. You can get hard copy or E subscription if your serious, otherwise limited magazine access is up online. Used to be strictly a Northeast publication but has a expanded range now.
The January issue has on overview to apple orchard production by U Minn extension with links to
commercial tree fruit production guides offered by Penn State. Dec archive has Expanding your Fruit Inventory...Finding a new crop.
My boss must have read that somewhere...he decided on a new vineyard for red seedless grapes and also espalier production on top of the thousands of trees and the 26 varieties of apples we already grow along with the peaches, pears, apricots, blueberries, raspberries, and strawberries we have too.
Obviously not intended for southern growers but here in the Northeast
U Mass has extensive fruit growing resource information available online. Look under publications.
And there's always
Cornell Fruit resources
I'm sure there are others too.
I want to see guys succeed at what they do
I really like that cider orchard plan of woodchuckdads