Can anyone tell me why the ends of some branches are drying up on this Thuja? I live near Tucson, Az. zone 9a, and the temperature is between 95 and 105F in the afternoons, but I water it using a soaker hose for 2 hours every second or third day at night when my finger, moisture meter and wooden dowel agree it's almost dry. It hasn't rained here since I planted the tree on May 8. I really don't want to lose this tree. It was shipped from Oklahoma. It has never been fertilized. Any suggestions would be greatly appreciated. Here are some pix showing where on the tree the branch came from and closeup. Could it be too much/little water or too intense sun 10 hours a day? The red tips make me wonder about too much sun. Please help! The small branch was completely dried out near the bottom of the tree. There is mulch around the tree if the prairie dogs don't dig it up to keep cool after watering! Any suggestions would be greatly appreciated.
Yes to both. Both of its parents (Thuja plicata and Thuja standishii) are temperate rainforest species, adapted to very high atmospheric humidity, plenty of rain, and not a lot of sun. Sorry, but Tucson is just the wrong climate for it. Try something like Arizona Cypress Cupressus arizonica instead, that's much better adapted to your climate.
Your climate may be a bit on the edge for it. But a few questions came to mind: 1. Have dog? 2. Is the discolor on the sunset side, or any particular side? 3. Use any mulch?
Thank you for your reply. The nursery I bought it from in Oklahoma did say the hardiness zone was 4 to 8. I will have to make a sunscreen for it like I did for my Orange tree. But for the Thuja I won't need the plexiglass side panals since our lowest temp in the winter is 20F.
No, I do not have a dog. The discoloration is in various areas on several sides. There is mulch around the tree if the prairie dogs don't dig it up to keep cool after watering! I will also try using a garden hose on the whole tree (in the evening) and spraying it with liquid Garlic against the possibility of Spider Mites.
What I've seen with arborvitae, is that they are packed tighter together in nurseries than some other plants. That can mean a bit of light sunburn when plants are removed from groups and placed in full exposure. Anyhow, keep nursing it along and see how it goes.
If it was tightly packed in the nursery it also spent 4 days in a box being trucked here from Oklahoma. And I did not acclimate it to the sun before planting. Am I right in assuming that the yellow tips on some branches toward the top could be new growth (see pic) or is this another problem? I will have to build a sunscreen (see pic) for the Thuja like I did for my Orange tree. Thanks for the reply.
Hi Any update on the thuja. I’ve had the same problem you seem to have the same symptoms as I did. Turns out to be sunburned from the high temperatures where on one side is brown and the underside isn’t on the leaf. I will be putting a canopy over mine as well during the first season here in the southwest.!!
