In spring, the very mention of frost sends gardeners scurrying for sheets, boxes, or whatever they can scrounge up to keep their plants safe from a possible cold snap. Take the guesswork out of what you can, and what you cannot plant until the threat of frost is over.
The threat of frost exists until the first full moon in June.
There’s truth to this old wives tale! Therefore up until approximately the first week in June:
It is not safe to plant: annuals, herbs, vegetable plants or greenhouse-grown perennial plants.
It is safe to plant: shrubs, trees, bulbs, and vegetable seeds sown directly into the ground such as peas, beans, corn, onion sets or potatoes.
If you can’t wait!
At least try to wait until the first and last frost days calculated in the Almanac. And if you just can’t wait until early June to start planting your annuals, vegetables, herbs and perennials, get ready to watch the forecast closely. Cool, clear nights with low humidity are signs of an impending frost. In case of a frost warning, you will need to protect these plants, or they could perish. You can protect your plants with these measures:
- The air temperature above wet soil is 5 degrees F higher than that above dry soil. Thus, plants should be well watered the evening before a frost.
- Covering plants can give you 2 to 5 degrees Fahrenheit protection. The covers can be laid right over the crop, but more warmth is provided by covers that are supported on stakes above the foliage. Any material can be used to cover the plants, however woven fabrics such as bedsheets and burlap are better insulators than plastics or paper. The best time to apply frost covers is in the late afternoon after the wind has died down. Remove covers the next morning before the sun hits them.
For those of you who like to buy your plants early in May, store them in a sunny, warm room and keep them well watered right up until it’s time to plant. Plants kept in garages often suffer from a lack of sunlight.
Happy (early) spring!