I just thought of a way to water your new plantings AND scare away the deer - I have one of these and they are excellent! The only way I have ever managed to get a harvest off my lychee tree here is to use this wonderful gadget:
https://www.amazon.com/dp/B000071NUS/
It scares off birds, squirrels, rodents and even raccoons because the motion detector does work just fine at night. Sprays 3 or 4 short bursts very suddenly and makes lots of noise in the process. If you can position it so that the water goes on the plants it might be a great thing for your situation there.
