Winterizing cedar and blue point juniper in containers


I live in Bloor West Village, in a condo/ terrace south facing. My trees are subject to high winds on the east side (cedar) trees. The juniper trees are partially protected by the BBQ unit.
The Juniper containers are lined with styrofoam with the exception of the round larger pots (two) cedars.Do I need to cover the branches ie burlap?
Thank you



Thank you for contacting Toronto Master Gardeners with a query about protecting your container grown evergreens. The contrast between the colours and textures of these evergreens would certainly add interest and beauty to your condominium terrace. The blue point juniper (Juniperus chinensis ‘Blue Point’), aka a Chinese juniper, is native to China, Japan, Mongolia and the Himalayas, and is tolerant of the Canadian Hardiness  Zones 5-10 (equivalent to US Zones 4-9). Your cedars are likely eastern white cedar (Thuja occidentalis), or a cultivar of this species; they are native to Ontario and will tolerate lower temperatures than your junipers, i.e. Canadian Hardiness Zones 2-7. It is wise that you have insulated the juniper pots as container grown plants experience conditions equivalent to 2 Zones below that of your area, which in Toronto, lies in Zone 6. Unlike deciduous trees, evergreens continue to photosynthesize, albeit at a slower rate during the winter.

You have identified a concern about the exposure to high winds from which evergreens are best protected in a terraced or balcony setting. Wrapping in burlap will help to protect the foliage from drying and breakage (in case of heavy snow fall). Other concerns are sufficient moisture and protection of the roots from the freeze/thaw cycle we experience in this area. External insulation could be added to the cedar pots. The following link, Terrace wintering, will take you to a summary of winter concerns and protections of evergreens and plants in a growing situation similar to yours.

For further information, please click on the following links: Blue Point Juniper and Winterizing / Insulating Balcony/Terrace perennial gardens*

Wishing you all the best in overwintering your potted evergreens!