I had 3x 7-8ft emerald cedars planted in the yard last summer (unfortunately regrets with who I had plant them). It seems they were planted way too close together and they started to brown top to bottom, one more severely than the others. I’ve removed the most affected one and shifted the middle one over to have a good amount of space – I checked the drainage, soil etc. as reading on here for recommendations. My question is for the affected brown segments on the remaining cedars whether I should leave the brown leaves as is, prune the whole branches/brown segments, shake them off? If I run my hand along the tree lots of brown leaves will fall off, especially on the sides that were close to each other (they were planted so close they were touching each other). I have checked for spiders or mites, nothing seen there. Is there anything else I can do to help with the recovery? Or is the same going to happen to these trees as well?
Thanks for contacting the Toronto Master Gardeners with regard to your Emerald Cedars. I am sorry that these are browning for you and yes it seems they were planted too closely. You have done the right thing by removing the worse one and giving some breathing room to the other two. However, it is my opinion that these trees are still planted to close to your fence. At the moment there is no light for the back of your trees, and they will continue to brown on that side. Please give the trees at least 3’ clearance from the fence. Unfortunately, the brown spots will not recover to its original look, and pruning will just create “holes”. I would shake off the excess brown foliage and continue with good maintenance as you have seen on our site. As you have already read; Watering deeply and thoroughly is key. Water at least one or twice a week – for several hours at a time for your cedars to establish. Water well into fall and until freezing time.
Don’t feel to badly, we get many many questions from readers about dying emerald cedars, so I would like to include a link to a site questioning the value of planting these in Ontario. Good luck with this!