Answer: Trees planted in midsummer will need extra care to get them through the hot weather. Dropped needles are not uncommon because roots are inevitably damaged during transplanting, and the root system cannot support all the leaves. Be sure to water them well about once a week through the fall. You may even want to put some shade netting over them to reduce the heat stress. Mulch around the base of each tree with bark or wood chips or cocoa hulls or, even better, compost. In the fall, add another layer of mulch so that it's about 3" thick to help the trees overwinter. You can also wrap them with burlap for winter protection.
Good luck with your trees!
Q&A Library Searching Tips