Poaky, sorry I havent even read anything on here for a bit, been super weird with the Coronavirus and stuff And work etc.
Anyway, I have a auto sprinkler system. The small hoses are attached to a timer on my spigot on my house and they water once a day around the warmest time of the day 4:30 pm. They are wrapped in that same foam noodle you use for trees to help prevent bursting. When its really cold, like below 20-25 degrees I have quick disconnect on the spigot.
The live oaks will not die in your greenhouse if they get water everyday. My greenhouse can get to 120 degrees and it doesn't phase my live oaks as long as they have water every day And a fan circulating air from outside. Litterally I open the greenhouse door and plug in a fan that shoots in air. If you have no way for electricity you can get one of those fans that works on solar to shoot in air. This is the first year I did that since I was so busy and didn't have the time to pull all my trees out like I usually do. They are all fine. The trick is lots of water every day. YOU CANNOT OVER WATER if it has good drainage
here is a pic
Instead of a hose on the timer you get an irrigation kit and connect the sprinklers in a daisy chain and the push the sprinklers into the buckets with ea tree. I went on cruise last summer in 2019 and needed way to self water..tested it for a week and it worked great.
you can adjust the timer for time of day or multiple times of day, and how long to stay on.
I leave mine timed on for 6-8 min..it's just sprinklers so so not a ton of water comes out.
Q