I have a really neat Juniper tree about 6 ft tall. It is in a large planter positioned against a wall in my front courtyard, western exposure. About 2 ft of the back of the tree the limbs have turned brown. Now there is a brown patch on the front near the bottom. I water it about twice a week. Any ideas?
Your juniper is showing signs of spider mite infestation. Trim back the brown spots since these areas are now dead. Then spray with Bayer 3-in-1 ready to use insect and mite control. I would recommend using this every ten to fourteen days until you see new growth in the areas you trim back. I use this routinely on our spiral junipers, about every two weeks, since spider mites are a big problem with junipers, especially in the Dallas area. The Link
Watering twice a week in a container isn't enough, especailly with a Western expusure in these drought conditions. I'll wager it's die-back from drying out too much.
I would have NO IDEA when it comes to plants, but I'm curious what the experts think of the possibility of a Juniper needing more root space. Don't they root real deep in natural conditions?