Apple tree not flowering
I have two apple trees in my yard in Takoma Park MD. One is a Gala and the other is a Macintosh. Both were planted 3 years ago and have been growing quite well. But the Mac has yet to produce a single flower. The Gala this year produced about 4 flower clusters. The Mac has grown very fast and I trimmed both trees this past winter. Any ideas on what I should be doing to get the trees to flower (at all or) better? It's kind of silly growing apple trees that don't produce apples. I'm also happy to share any additional information that would be useful. A few additional data points. 1- I did have the soil tested before I first planted. It was heavy clay and acidic. I ammended near where they were planted as directed, including adding lyme and other minerals. I have not retested since. 2- They are watered via a drip system. 3- I do spray the trees with organic controls... Neem oil primarily. 4- The trees do not get full sunlight all day. They do get 6 hours or so of direct sunlight, and then a few hours of dappled shade. 5- I also have 2 peach trees right next to the apples. They have produced peaches quite well.
Montgomery County Maryland
It is difficult to grow tree fruits in MD as they can be susceptible to insect and disease issues and will require a spray schedule for control. There are also cultural and environmental problems. Apples are one of the hardest tree fruits to grow.
It is too warm here to produce a reliable crop of McIntosh apples. We also do not know what rootstock the apples are growing on. Some may take 4-5 years to bear fruit. The amount of sunlight that you have is minimum but okay.
Some other reasons for no flowers include low temperatures damage in early spring - trees may leaf out without flowering. Leaf buds are hardier than flower buds, Over-use of nitrogen fertilizers prior to bloom period. Reduce applications of high nitrogen fertilizers., stressful conditions, etc. http://extension.umd.edu/growit/cultural-and-environmental-apples-and-pears
See more on apples http://extension.umd.edu/growit/fruits/apples
If you want to grow organically, you may want to try growing small fruits such as blueberry or blackberry.