Answer: Japanese maples are naturally very slow growers and very light feeders, so fertilizing would not be the answer. Overfertilizing can cause "root burn" so if you used the recommended amount of Hollytone then you might try to remove the additional fertilizer sticks. An annual application of Hollytone per the label directions would be ample fertilizer for this tree. Overfertilizing is actually worse than no fertilizer at all.
More important is to avoid disturbing the roots (planting around the tree would damage its roots and/interfere with their growth) and also use an organic mulch two to three inches deep year round. This helps keep the soil moist and cool in summer, and also breaks down slowly over time to feed the soil.
The pattern of where the leaves are not showing that you described is typical of winter injury. Winter damage occurs when temperatures are excessively cold, and/or the site is extra windy, and/or the soil has become dried out thus causing the tree to dry out.
The dry conditions we experienced this winter and spring could have caused the tree to dry out and die back as a result. Also, your zip code places you in USDA winter hardiness zone 6A, which depending on your microclimate could be as cold as zone 5. Many varieties of Japanese maple are not dependably winter hardy in areas as cold as zone 5. So this might simply be a case of cold damage.
However, osciallating temperatures can also cause injury like this. If a freeze occurs while the buds are swelling and the tree is just beginning to leaf out, the cold snap can kill the leaves. If this is what happened, it is stressful on the tree but the tree should releaf in time assuming it is fairly healthy.
If the branches still have green inside the bark, I would be very patient waiting for the tree to leaf out. Check the tips of the branches and work your way toward the center looking for live wood. Live wood has green inside the bark and is flexible while dead wood is dried out and will snap in your hand and is discolored brown or gray. Remove any dead wood as it will not sprout leaves. The live wood should grow leaves eventually.
In the meantime the most important thing you can do for this tree is make sure the soil is moist like a wrung out sponge whenever it is not frozen. This means damp, not soaking wet/saturated and not bone dry. To know if you need to water, dig into the soil beneath the mulch with your finger. If it is moist do not water yet. When you do water, water slowly and thoroughly so it soaks down in about ten inches. It is better to water deeply and less often than to sprinkle lightly every day. After watering, wait a few hours and then dig down and see how far it went, it can be surprising.
Good luck with your tree.
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