Question
Hi Jim, i have a cedar hedge which i share with my neighbor, it is on the property line. We each take care of our own side of the hedge. My side is really nice and straight however my neighbor has let his side go and i have offered to trim his side of the hedge.  The problem is that some of the trees are much wider than the others. I was told that when trimming a cedar hedge to cut back 1/3 of the new growth (the tan or green color of the branch). I need to know what will happen if i cut back the old growth, the brown part of the branch, in order to straighten out his side of the hedge the best i can.  Also, if it needs any particular attention afterwards (watering, fertilizer etc.).

I have tied the largest branches inward but they still need alot of trimming????


thanks

Answer
If you cut conifer trees (cedars are one) back past the green foliage the branch will die. Conifers do not leaf out from bare branches like hardwood trees will do. I would prune them back the 1/3 of the green foliage and then next spring prune them again back 1/3. It will take a couple of pruning's to get the shape you want. If you try and prune back all at once you will leave bare spaces in the crown foliage.

Locate the dead zone at the interior of the tree. Do not cut into or near the dead zone. If the dead zone is exposed by pruning, new growth will not appear and the tree will be permanently deformed. Keep this dead zone in mind while forming your plan for the tree.

Then I would fertilize with 10-10-10 fertilizer at the rate of 1 lb per inch of trunk diameter scatter this under the hedge and water it in. Apply the fertilizer just before a rain event and you will not need to water.