Hi, iam wondering our cedars are facing west but are partially shaded by a large maple tree.The trees look decent but patchy should we move them to our back yard that has full sun for 6-8 hours.we also have another close to the house facing north and the back of the tree is very brown but front is nice and green. Any help would be greatly appreciated. Thanks.
Thank you for contacting Toronto Master Gardeners.
Moving any trees in the middle of summer is a tough time for the trees. Plants are best moved in fall or spring when there is plenty of water and the temperature is cool.
Cedar trees can have full sun or partial shade to thrive. In the winter if there is too much sun hitting them it can trigger photosynthesis on a warmer day. This is not much of a problem if the plant has stored water but can become a problem if there is a winter with fluctuating temperatures and the cedar uses up its water reserve. When this happens the leaves will begin to brown but not until the late spring or summer. It takes time for this to show. Is it possible this has happened with the spotty ones as the maple tree would not block the sun in the winter?
With the areas that are brown it is good to make sure you do not have spider mites. They are very small and hard to see. If you put a white piece of paper under a branch and shake the branch the spider mites will fall onto the paper and you will be able to see them then. If this is an issue, the link below will take you to another response on Emerald Cedars with information on dealing with spider mites.
Once a branch turns brown on a cedar there is very little you can do. New growth and leaves only come from new wood, so this years growth. Older wood will not bud out for you. If the cedar by the house is moved the brown area is not likely to green out for you. If the green side is the visible side and looks good then you are probably best leaving it and enjoying it as is.
I am including a link to another answer on cedars from our archives that may help you.