Cold snap alert: cover those plants

By Carol O'Meara, CSU Extension Boulder County

The cold snap predicted for Thursday and Friday is not going to be kind to the garden.  Yes, we can use the rain, but the snow and below freezing temps means gardeners should get ready to cover up.  Grab tarps, plastic sheets, buckets, and keep your therapist on speed dial for the inevitable call to cry on their shoulder; this freeze is catching us after we’ve planted.

Tender vegetables like tomatoes, peppers, eggplant, cucumbers, napa cabbage, or squash should be capped with an extra bucket, coffee can, Mason jar – anything that will trap the heat from the soil.  If the planted area is too large for individual buckets, set up a tent to cover the plants with plastic.  The trick is to trap the soil heat, so ensure that the plastic reaches the ground on all sides.  Weigh it down so the wind doesn’t blow it to Kansas and keep the plastic from touching the plants you’d like to protect.

Potatoes, onions, beets, and other root crops nosing up from the soil will be fine under a thick, warm blanket of mulch.  Pile the straw or grass clippings up over the plants to keep them snug under at least six inches of mulch.  You can uncover them after the freeze is over.

There’s not much we can do for the trees but if you have smaller perennials or roses you’d like to protect, swaddle them in plastic as well.  If possible, pull containers into the garage to protect them or cover them with buckets or plastic.  To keep pots from freezing, group them close together and stack bales of straw around them, then cap them with a blanket or tarp.

Make sure that you uncover the plants as soon as the cold snap passes by; things heat up very quickly under plastic and you don’t want to steam cook your plants.