Protecting plants from cold weather

Written by Doug Oster on .

blog lettuce covered underneath 0513Lettuce is not tender, but will be happier when covered with a floating row cover to protect the leaves from frost. Photo by Doug Oster

There are rules about planting tender plants in the garden. Unfortunately we gardeners get lulled into a sense of false security after weeks of nice weather. I plead guilty to planting cucumber plants, caladiums and few others which resent temperatures under 50 degrees.

My mother always said not to plant tomatoes and other frost sensative plants until Memorial Day. That was years ago and in a little bit colder climate, but the advice is still sound today.

Most plants will survive the cold weather on the way, but will be happier with warmer soil temperatures and a little protection.

If the garden is already planted, here are some ideas to keep your plants thriving.

A floating row cover is the tool I'm using to cover anything in danger. It's a spun bound translucent lightweight fabric, so light in fact, the plants themselves can hold it up. One of the biggest mistakes gardeners make is covering their plants with something heavy enough to damage the stems, foliage or flowers.

Whatever you use to cover the plants, try to have something to hold it above the plants so the frost is on the covering and not coming in contact with the foliage.

I was also given some plastic skylights which work just like a greenhouse in the garden. I can move them around to different beds to protect the most tender plants.

If you can't cover everything, make sure it's watered. Moist soil holds and releases more heat than dry soil and creates a humid environment which will help retard the frost.

Usually we never want foliage to stay wet overnight, but it's another way to prevent frost. Spray the plants and the water will freeze on the leaves instead of allowing the cells to freeze inside the plant which will most likely blacken and destroy the leaves.

Water requires a certain amount of energy to change from a solid to a liquid. It gives off this energy when it changes from a liquid to a solid. The water releases this energy, creating heat.

Lots of gardeners also swear by spraying frosted plants in the morning before the sun hits the leaves.

There are lots of plants we don't have to worry about. Any perennial shrub, tree or border plant will be fine. No need to cover those. Azaleas, rhododendrons, spring bulbs, hostas and more will shake off the cold.

The 10 day forecast looks pretty good for getting the garden planted. Remember, it's soil temperature, not air temperature which the plants really care about. Nothing wrong with waiting to plant.

blog covered lettuce 0513This simple frame make out of PVC tubing will keep the covering from touching most of the plants.

blog lettuce skylightThis simple plastic skylight will keep plants growing strong when it gets cold.




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