(Dogpound Alberta Canada)
Hi Im looking for the hardiest sedum and succulents to plant in chinook country. We are 30 kms north of Calgary and just in the foothills west. We continually fluctuate between -20 and up to +15 through the winter months. If you could let me know what the best combos would be and the best way to winter them, that would be great and then I would like to order them.
Drought Smart Plants reply:
Hi Deana, you truly are gardening in challenging conditions - to those that don't know the meaning of the word Chinook, this is a type of climate where warm winds can melt several feet of snow overnight, causing flooding and other issues, followed by freezing temperatures again.
The main trouble with Chinook conditions is this re-freezing once the snow cover has been melted.
The plants sense the warmth, and start to grow, leaving the cells of the plant in a very precarious position of being full of moisture (from the melting) which then freezes again.
Luckily, some of my favorite plants are able to withstand this - provided that one important criteria is met: the ground absolutely must be well drained.
No plant, hardy succulents included are hardy enough to withstand freezing temperatures in waterlogged ground.
I recommend a high proportion of sand or gravel, in a raised bed to bring the roots of the plants above the commonly clay soil of your area.
There are many plants to try - some of the best are Sempervivum, which luckily are on sale right now: Sempervivum Co-op.
Sedum are very hardy and able to withstand very challenging conditions; I recommend a random selection so you will have some types survive even if the conditions aren't suitable for others.
See the page here for ordering: Sedum for groundcovers plugs.
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