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Weathering a late winter cold spell

The last thing gardeners on the West Coast need now is a severe cold spell … but according to Environment Canada, that’s exactly what will happen this week.  Here is a list of the most critical things to do in your garden.  1 – Move all outdoor containers out of the cold north-easterly winds and into a more protected spot.  Even an enclosed garage will do.  If the plants in the containers are not hardy (zone 6), wrap them with a proper insulating material such as the new insulating cloth or even a blanket.  Both must be dry to be effective.  Even if the plants freeze, this will certainly minimize the severity of the frost.  Be sure to water all the containers thoroughly as well.2 – If you’ve uncovered your roses, cover the bottoms of the plants back up with a good insulating material like sawdust or bark mulch.  You’ll need at least 12 inches (30.5cm) of protective material.  Remember:  tree roses have two grafts on the bottom and on the top and both need to be protected.3 - Most hardy (zone 6) flowering shrubs will be fine in this weather because temperatures have been cool enough to hold them back.  How-ever, I worry about mophead and lacecap hydrangeas because their buds are now formed and are quite soft.  If you can put three to four stakes tightly around them just above the plant and wrap them with a good insulating material, it will save the buds, especially if they are in a windy, exposed location.  The more tender varieties of azaleas, rhododendrons and camellias and any other zone 7 or 8 broadleaved plants should be protected as well, especially if they are exposed to north-easterly winds. 4 – Believe it or not, most the bulbs and perennials, that are just emerging, will be fine. Their flowers are still in the ground.  Snowdrops and aconites will be okay too even if frozen solid.  More tender perennials, those rated zone 7 and 8 and varieties like Spanish lavender and cape fuchsias, would benefit from a little mulching.  If you have just planted some of the new flowering hellebores with fresh flowers, cover them with Remay cloth or insulating fabric to keep the flowers in fine shape.5 – Water the plants under the eaves of your home where they do not get moisture in order to rehydrate them and prevent desiccation.  Do a thorough watering.6 – As a precaution, move all very tender plants and started seedlings away from very cool windows and entryways until the worst of the cold is over.  Make sure all your stored bulbs and vegetable crops in cold spaces and garages are wrapped and protected as well.  If you have a greenhouse that’s unheated, you will either have to move your plants or insulate it with poly and then heat it.7 – You may want to add more mulch to give a little more protection to any recent plantings of tender perennials, fruit trees and small fruits.Every plant you have outdoors, that is zoned for your area, will be fine with the few exceptions I have just mentioned.  Very early and very late cold spells are the difficult ones because of plants either not being hardened off or pushing ahead in late winter.  With this little bit of extra attention to your garden, you should be fine.  Good luck!