Storing plants in pots over the winter

(Question)

We purchased a smaller Crimson Sentry Maple, a weeping Cypress, and a juniper prince of wales for a front bed. Can we plant these temporarily in their pots until next spring. We are having a water feature installed in the spring and will likely have to move these to a different location.

(Answer)

Dear gardener,

Yes, you can place them in the ground in their pots until ready for their final location in the spring.

Damage to perennials, trees and shrubs is caused by heaving (the cycle of ground freeze and thaw during winter months). By sinking the pots into the ground, you can use the soil as an insulator. To avoid heaving, add soil around the base of the tree and evergreen shrubs and also use mulch (such as cedar mulch or shredded leaves) around the pots.

In addition, extreme cold, winter wind and strong winter sun can damage plants, particular evergreens. Evergreen plants (like your juniper and cypress) maintain their needles during the winter. As such, the processes of respiration and transpiration continue, even during the winter months. If they can’t continue to draw water through their roots, it interrupts their biological cycles and ultimately causes dessication (drying of their needles). To avoid this, make sure you water the ‘sunk’ pots during the fall, especially during periods of hot weather, until the ground freezes.

For more information, please refer to other entries the topic on our website:

http://www.torontomastergardeners.ca/index.php/askagardener/overwintering-plants-in-pots/

http://www.torontomastergardeners.ca/index.php/askagardener/winterizing-perennials/

Best of luck and thank you for contacting the Toronto Master Gardeners