Will Pansies Die if Exposed to 26 Degrees?

Preferred Climate

• Pansies grow best when days are warm and sunny and evening temperatures remain from 40 to 65 degrees Fahrenheit. They prefer cool, moderate climates. Pansies begin to fade when daytime highs exceed 75 degrees F and quickly die when temperatures remain above 80 degrees. For this reason, pansies may overwinter in warmer regions but usually die when summer heat sets in.

Perennial or Annual

• Pansies are sometimes grown as short-lived perennials in U. S. Department of Agriculture plant hardiness zones 6 through 10. In areas with moderate climates, pansies may reseed themselves and return the following year. However, in regions where the summers are too hot or winters too harsh, pansies must be grown as annuals and replanted each year.

Winter Care

• Healthy, well-mulched pansies can withstand short spells of freezing temperatures, even into the single digits, as well as frost and light snow. They generally will not survive sub-zero temperatures. Placing a thick layer of pine straw, dried leaves or bark around your plants helps prevent soil from freezing and retains moisture. During the winter months, applying a 15-2-20, high-nitrate liquid fertilizer every two weeks keeps plants strong and vigorous, making them more likely to withstand cold weather.

Freeze Protection

• When temperatures drop below 15 degrees F, leaves and flowers will freeze if the plant is unprotected. If a hard freeze is predicted, cover your plants with several inches of straw until moderate temperatures return. Don’t be alarmed if your pansies appear pale and wilted after exposure to sub-freezing weather. They will revive once the weather warms up. Freeze-damaged flowers and leaves should be removed to keep plants bushy and prevent fungal diseases.

Planting Times

• In regions that experience long, harsh winters, seedlings should be set out in spring, after the ground thaws. Pansies grow best when soil temperatures are at least 45 degrees F. If summer temperatures are moderate, pansies will bloom up until the first frost. In regions with relatively mild winters, pansies are often planted from October to December to give the roots time to become established before spring. Planting pansies in late summer or early fall, when temperatures are still very warm, can cause leaves to yellow and stems to grow long and leggy.