Planted 7′-0″ cedar as per requirements: dig hole twice the width of the pot,and plant 1″above grade, back fill, and slope away from the tree. Also the hole was watered prior to planting
Thank you for contacting Toronto Master Gardeners about your cedar. Browning cedars are quite common, and we get many questions on this topic. Based on the information you provided, there are numerous possible reasons why your cedar is turning brown.
What was the condition of the tree when purchased? It may not be obvious at purchase but if the tree was not cared for properly while growing, and at the garden center, it may already be failing when you take it home.
Proper planting and post-planting care are critical. Our Planting a Tree for Life: A Toronto Master Gardeners Guide provides complete details on selection and planting a tree. Here are some factors that affect planting success.
- Is the tree in an exposed or sheltered location?
- What else is nearby- a building, sidewalk, road, garden or? Road salt can damage nearby plants.
- How much sun does the tree get? Cedars prefer full sun to partial shade.
- What type of soil is it planted in? Does the soil drain well? Clay soil drains poorly, and poorly draining soil could cause root rot.
- Was the root ball teased out before planting? If not, the roots may be girdling – growing around each other – instead of growing out from the tree.
- How frequently and how much water has the cedar been given since planting? Watering deeply and thoroughly (at least once or twice a week after planting, especially in hot summer conditions) is key so the cedars’ roots can take hold and spread.
- Did you mulch the tree after planting to maintain soil moisture?
- Did you fertilize the tree after planting? Fertilizer is not recommended for a new planting.
There are various pests and diseases that could cause cedar foliage to turn brown such as aphids, scale, spider mites and fungal diseases.
We would need more information on the specific tree variety, when and where the tree was planted, details on the location and extent of the browning, and preferably a photo of the tree, to provide a more precise answer to your question.