Frost Heave

Exactly what causes heaving, and can it be prevented?
gby1112_4a_mulch

gby1112_4a_mulch

Heaving, or frost heave, occurs when soils are subjected to alternate periods of freezing and thawing. It can be so severe that plants are literally shoved out of the ground. According to master gardener Paul James, heaving is most common during late winter or early spring when there is abundant rainfall and varying temperatures.

Heaving can occur in all soil types, but it is more prevalent in soils that don't drain well, especially soils containing a high percentage of clay. Soils that retain moisture (like clayey soils) expand when they freeze and, in the process, create an upward pressure that literally lifts the soil.

To prevent heaving, James suggests improving soil drainage by adding compost or another form of organic matter. He also recommends adding insulation to the soil surface, especially during the peak heaving season. The best insulation is shredded wood mulch. Spread a three- to four-inch layer of mulch around--but not quite up to--the base of the plant. Of course, if you live in an area of the country where significant snowfall is common, then heaving shouldn't be a problem since snow is an excellent insulator. In fact, one foot of snow will insulate the soil to the equivalent depth.

Keep Reading

Next Up

Keyhole Gardening Tips

Try this inexpensive, green solution to growing food in drought-prone terrain.

14 Simple Gardening Tips and Tricks

From using leftover coffee beans to preventing dirt from getting underneath fingernails, master gardener Paul James shares his top 14 tips and shortcuts to make spring gardening a breeze.

Tips to Perk Up a Bleak Winter Garden

Recommendations for adding cold-weather appeal to the garden.

Topiary Gardening Tips

Create a showstopping garden sculpture with expert topiary care and maintenance tips for beginners.

Saving Citrus From Frost

Discover ways to protect your outdoor citrus from the elements.

11 Must-Try Gardening Tips for Newbs

Jealous of your neighbor's lush garden? We'll get you that green thumb in no time.

Plant a Winter Garden

Add pops of color to your winter landscape with plants and shrubs that add interest and will attract and support wildlife.

Protecting Garden Pots During Winter

Tender plants will die if their roots are locked in cold, wet soil in winter, but you can protect them during fall.

1,000+ Photos

Browse beautiful photos of our favorite outdoor spaces: decks, patios, porches and more.

On TV

Follow Us Everywhere

Join the party! Don't miss HGTV in your favorite social media feeds.