Frost Heaving and Plants

In recent years, winter weather has been interesting – with stretches of warm, almost spring-like days interspersed with freezing and snow. While the spots of warm weather are great for us, they can wreak havoc on some of our plants.

The wide temperature fluctuations cause repeated freezing and thawing of the soil, expanding and contracting the soil with each cycle. Eventually, this cycle can lift (or heave) some plants up out of the soil. The heaving may break off some of the plant’s roots and can also expose the remainder of the roots to freezing temperatures and drying winds.  The injury from the exposure can seriously damage or even kill plants.

Frost heaving is more likely in soils that have poor drainage, although it can occur in other conditions. Plants with shallow roots like Heuchera and Coreopsis are more likely to heave. Also anything planted in late summer or fall is more prone because the root systems may not have had enough time to anchor the plant into the soil.

To prevent damage, use the periodic warm spells to inspect your gardens – particularly newly planted areas. If plants have lifted out of the soil try to gently push them back into place. Cover any exposed roots with soil. If possible, add mulch around the plants to help moderate temperature swings.

Most plants will recover just fine after frost heave as long as their roots are put back underground quickly.