
I've taken several different approaches to cold protection throughout the yard. First, I dragged the Jaboticabas, Ujukitsu, Ruby Grapefruit, and fig cuttings into the shed, and the Meyer Lemon and Surinam Cherry into the garage. These are all in 10-gallon pots, so they're relatively easy to move around.
There are several ways to protect your trees. A study conducted by Danny Gabb of Simonton, Texas found that the most effective way to protect a young tree was to surround it with wire fencing, and then fill the fencing to the top with leaves, insulating the tree. The best and most effective cold protection method I have found for use for in-ground trees is to wrap the tree in C7 Christmas lights,bank mulch/leaves around the graft, dump a big bag of leaves over the tree, and cover all the remaining exposed branches with a fitted sheet.
I can get away with this now because my trees aren't that tall, but when they get bigger I'll have to devise another method. For example, my Republic of Texas orange is way too tall to cover, so I banked leaves around the graft, hung lights in the tree, and placed a covered 5-gallon bucket of hot water under the tree.
The Mexicola Grande and Lila avocados are supposed to be cold hardy to low 20's and high teens respectively, although I suspect their rootstocks are Lula, and only hardy to the mid to high 20's. Last year it got down to 17 degrees in my yard, and though it killed several twigs on the Mexicola Grande, the tree survived and recovered very well. To protect these, I banked potting soil around the grafts, dumped a big bag of leaves over the tree, and placed a covered 5-gallon bucket of hot water next to the base of the tree.
All of the potted citrus on the porch were covered with sheets or plastic, and I placed 60W bulbs or Christmas lights at the base of the trees. When I went out this morning at 5:15am, the sheet I had placed over the Moro blood orange and the Calamondins had blown off. I don't know how long they were uncovered, but I won't know how bad the damage is for a week or so.
I have 3 satsumas that I'm hoping make it because I ran out of lights and sheets. The Owari satsuma (on flying dragon) is supposed to be very cold hardy anyway, and it is planted next to my 300-gallon rain tank with leaves banked all around it. It should be Ok. The Okitsu Wase (on trifoliate) is planted right next to the south side of the house, and I covered it with leaves and set a 5-gallon bucket of hot water next to it, so it should also be fine. The Miho satsuma (on sour orange) is in a 30-gallon pot placed in a sheltered location, but with no lights or bucket of water. I wrapped the graft with an old towel and t-shirt, and covered the rest of the tree with bubble wrap. I hope it makes it. Good luck everyone!