In early spring, it’s easy to plant too early, especially when you’re fighting spring fever. A few warm days can coax even the most experienced gardener to throw caution to the wind and tuck warm-season annuals, like coleus, begonia and petunia, into containers. Or maybe you decide to get a jump on your tomatoes and slip seedlings into the garden sooner than you should. A sudden cold snap can endanger these early season efforts—but you can protect plants with these easy strategies.
Shift Pots to a Protected Spot
The easiest way to protect plants when frost threatens is to move them to a sheltered location, such as on a porch, beneath an elevated deck or inside a garage or shed. On a porch, cluster pots together against a wall. Huddling containers in a small group makes it easier to cover them with a frost blanket or tablecloth, if temperatures require. The small cluster also raises humidity around plants—which helps elevate temperatures near leaves since moist air takes longer to cool.
Make Plants Mobile
Gather plants that you haven’t tucked into soil or containers in a wagon or wheelbarrow, and stash them in a garage or garden shed overnight. Just be sure to wait until temperatures rise before moving plants outside the next morning to soak up some sunshine. Use caution with this method if you’ll open the overhead garage door for an early morning exit. Temperatures may still be freezing at this point, and opening the door will allow a rush of frigid air to envelope plants.
Lower Hanging Baskets
Lower hanging baskets from their hooks and set them on the ground in a protected location. If baskets are too full to sit directly on the ground without breaking stems, place them on an inverted bucket or pot. The reason you want to move baskets is that air near the ground will stay warmer longer than air at hanging level.
Water plants just before the sun sets. As water evaporates from soil overnight, it will warm the air around plants. Use caution when watering containers if overnight lows are dipping below 32 degrees Fahrenheit. Soil in a large pot shouldn’t freeze solid at that temperature, but smaller soil volumes, like in 4-inch pots or cell packs, might. For these small containers, toss a beach towel or old sheet over plants for extra protection.
Linen Closet Plant Covers
Keep a supply of plant covers on hand fresh from the linen closet. Towels, tablecloths, sheets, blankets—any type of fabric works well to keep frost from forming on plants. Pillowcases make effective vertical covers for individual plants or pots. Get covers into place before dusk. As soon as the sun sets, soil starts releasing heat, and you want your cover to trap that heat around plants. Remove covers in the morning, after frost melts.