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Out Cold

Prepare your plants for colder weather with these wintering tips.

Story by By R.J. Davey

Hard freezes and cold weather can harm ornamental plants, especially winter-flowering species. It takes a bit of planning to protect them over the winter, but with the right preparation it’s relatively easy. While cold weather does impede growth and flowering, it doesn’t necessarily mean that your plants will be killed or harmed when the temperature drops. Many plants have the ability to adapt to atmospheric changes adequately. Plants do survive hard freezes. If you want to keep your precious plants in top condition over the winter so they can thrive in the warmer spring and summer months, follow these simple tips.

1. Cover flowering plants and buds 

Plants most at danger from damage caused by cold temperatures and frost are those with fragile flowers and buds. Newly opened flowers display unsightly brown spots on their petals, while fully open flowers can turn brown and die. Buds can freeze completely and drop from stems. The way to avoid this is to cover plants with sheets or frost covers. Don’t use plastic coverings as they can cause an oven-like effect in direct sunlight.

2. Remove buds and let them open inside 

Another way to avoid the disappointment of losing those pretty flowers is to remove them from the plant and let them open inside your house. Do this in advance of any predicted freeze to protect their vibrant colors and brighten up your home at the same time.

3. Water in advance of a freeze 

Watering before the ground freezes helps the plant absorb as much moisture as possible. This is especially good for annuals and potted plants. Water both roots and above-ground shoots.

4. Use mulch 

This works by keeping the temperature around the roots stable, mitigating the effects of hard freezes on the soil.

5. Compost well 

Compost adds vital nutrients to the soil, which your plants will need over the winter. Don’t add more than three inches of compost, though.

6. Bring your houseplants inside 

Houseplants are particularly vulnerable to frost, so bring them inside the house. Keep them in a position where they can receive plenty of natural sunlight (about five hours a day), spray them with insecticide, and water them thoroughly with an insecticidal solution to keep any unwanted bugs at bay. Keep them away from drafty areas and vents, and don’t overwater them.

7. Use extra protection for containers 

Plants that grow in containers also are vulnerable to frost, so protect them with commercially available coverings or sheets, and keep them close to foundations and under eaves.

8. Don’t fertilize 

Fertilizer encourages plant growth, and new growths can be killed easily by a sudden cold snap. Save the fertilizer for the warmer months and let your plants rest and rejuvenate over winter.

9. Water more sparingly 

A deep watering once a week during cold dry periods is sufficient. Your new plants will benefit from watering them less. Don’t worry about the regular watering cycle.



Freezing temperatures

Light freeze:

29 to 32 degrees. Tender plants are killed.

Moderate freeze:

25 to 28 degrees. Widely destructive to most vegetation.

Severe freeze:

24 degrees and colder. Heavy damage to most garden plants.



Lowcountry frost dates

Last spring frost: March 10

First fall frost: November 29

Growing season: 263 days