I have just read your reply to the gardener who planted 200 cedars, now turning brown in which you mention overwatering causing root rot and wonder if I have committed the same error. I planted 6 7′ cedars in a mostly shady location a week ago, using loam augmented with peat moss and sheep manure & with the addition of liquid “transplant shock preventer”.
Since we are in an extreme heat situation, I have been leaving the soaker on for 2 hrs at a time , 3 evenings a week. One of the cedars is turning quite brown at the base, although the rest of the plant is healthy looking. Will new growth appear where it’s now brown? And how do I know when enough is enough with the watering? I’m 80 years old & sure don’t want to have to repeat the job!Thank you.
Thank you for contacting Toronto Master Gardeners with your enquiry. In reviewing our Ask a Master Gardener replies regarding cedar (Thuja) problems you will have noted how frequently cedar hedge problem arise.
We applaud your planting and watering regime. One method of determining if sufficient water is being applied is to dig down about six inches (15 cm) to determine if the soil is moist at that level. If you find the soil overly damp try leaving the soaker hose on for less time, say one hour three times a week. Cedars are known for their love of water and one week of extra water would not likely cause the roots to rot.
Cedars do not generally ‘break’ or put forth new growth from old wood, however I have found that it does occasionally occur if there is an adventitious bud announcing itself as a little bright green nub at that point.
The following link provides some encouraging information:
Some trees can create adventitious buds in places where there were no buds or branches before. More often, trees have dormant buds near where they may have once had branches. In either case, exposure to light or a major loss of wood higher up in the tree may cause these buds to sprout and grow into new branches. However, this re-sprouting on old wood becomes less likely as the tree gets older and is less likely in evergreens than in deciduous trees. I have no specific knowledge of cedar trees in this regard, but my guess would be that cedars and arborvitae might be a bit more likely to re-sprout on old wood than a typical evergreen. Nonetheless, I would not expect much if this is an older tree.
Perhaps the shrub had an injury during transportation or planting which damaged or broke the twig which is now turning brown. A dog peeing on the tree is another possible cause of browning foliage.
We wish you well with growing your new cedars. Your careful gardening practices should mean that you will not need to repeat the job!