Extreme Cold Warning | February 8th, 2021
As the cold outbreak has developed over the weekend, the forecast now for some parts of the coast are for lows down to -7 to -12oC (10-20oF) by Wednesday night. This is much, much colder than our usual Artic outbreak and well into damaging range for many of our coastal gardens plants. There doesn’t appear to be any significant snowfall in the forecast that would provide valuable insulation. So today, beef up your insulation on all above-ground vegetables, even the hardiest ones we don’t usually worry about; kale, hardy leeks, Brussels sprouts, as they would be damaged at these lows. If possible, pile on more leaf mulch around plants and then cover with tarps, plastic sheets, old blankets, etc. New subscribers can find more info about cold preparations in my Jan. 22 message (below).
Unfortunately, because it has been so mild this winter, some plants are at greater risk of cold injury now because they have started to grow. Artichokes are especially vulnerable so pile the mulch back over the crowns of plants and add an extra covering (e.g., tarp or very large pot turned over the crown). Fluff up mulch and cover strawberry plants to prevent frozen soil from heaving up the crowns.
If you have a lemon or lime tree outdoors keeping warm under a cover a with heating cable or Christmas lights, harvest any ripe fruit today (note that lemons can be ripe without turning yellow; I picked dozens of ripe lemons from my tree yesterday). Put extra covers over the tree to insulate it: at these temperature, the heating system may not be enough to prevent fruit and buds from being frosted.
Don’t forget you irrigation system, either, which might have valves or other parts that are vulnerable to freezing. If you have fruit or vegetables (or dahlia tubers, etc.) stored in outbuildings, bring them indoors for the duration of the cold snap. Bring indoors potted plants that usually can stay out or at least drag them against the house and cover them.
OKAY, folks, get out there now and do what you can for your garden!