Taking precaution during the coldest periods of winter will help to keep the herb and vegetable garden productive and a source of outdoor pleasure on sunny days. Frost tolerant herbs such as Parsley, Oregano, Thyme, Marjoram, Coriander, Rocket and many more will still reward you with fresh flavour for your favourite dishes.
Clouds will help to insulate and slow the loss of the heat, but a cloudless, wind free night will afford no protection whatsoever. The temperature within the soil and in the plant’s cells may even drop to a few degrees colder than the air.
As the temperature drops, the moisture in the air condenses into dew, which then freezes when the temperature reaches 0° C on the plant surfaces.
At 0°, damage to most plants may be minimal, and only affect a leaf or two. However, if the temperature drops far enough for the plant cells to freeze, non hardy plants will die.
Weather conditions can bring about a frost, even in supposedly frost free areas. It is important to heed the warning when your local forecaster announces ‘a chance of frost, and take precautions to protect your garden. Take special care after new moon up to 1st quarter (Moon Gardening almanac).
Often times it is possible to extend your growing season by several weeks if you are able to keep your plants alive through a single early frost!
Covering your herb and vegetable garden with frost guard will not only prevent damage but ensure you will have stronger and healthier plants to harvest from as the spring season starts.
If your efforts were too late, or too little to protect your plants from a frost, resist the urge to cut off the damaged parts of the plants. To a certain extent, these dead leaves and stems will provide limited insulation from further frost damage. You will have to go back and re prune your plants in spring anyway.