Expert advice Protecting plants from frost

If your prized plants have been caught by the cold, HANNAH STEPHENSON finds out how to rescue them

- HANNAH STEPHENSON

A frosted rose.

(Grace Marr/RHS/PA)

We may be experiencing warmer winters due to climate change, but you can’t rely on your tender plants surviving the hard frosts of winter.

Before you know it, tender plants left outside can succumb to frost damage as autumn turns to winter, sometimes ending up a soggy mass which no amount of TLC will help put right.

Sudden extremes of weather ~ a really warm summer followed by a really cold snap - can lead to the loss of some shrubs and other plants which have previously survived for years, explains Jonathan Webster, curator at RHS Garden Rosemoor in Devon.

A lot of plants you may have considered hardy could succumb to frost if they haven't had time to harden off, he explains.

“If they haven’t have time to get used to that cold and shut down, it can cause them more damage. Even hardy plants could have damage to the newer foliage on the tips of the plants.”

“We live in a frost pocket here, as Rosemoor sits in a valley and I remember one year when we had a really warm summer and then a really cold spell in early December.

“One week it was about 12 degrees, and then the next it dropped to minus nine and we had lots of plants you would consider hardy-ish - but because they hadn’t hardened off for winter and hadn't had that slower transition from warm to cold, we lost some.

“We had 10-year-old pittosporums (evergreen shrubs), which come from New Zealand, and they literally all just died”

“(f it’s a dahlia or a herbaceous plant, or what we call a tender perennial, those softer plants go black or floppy and the tips start to collapse,” says Webster.