sharp frost
severe frost

The plants will freeze, so care should be taken in times of severe frost or freezing temperatures.

The court found that the severe frost could not have been in the contemplation of the Water Works.

In 1998, a severe frost struck and the tree stopped bearing fruit for a number of years.

Fleeces are probably best known for their ability to protect plants from quite severe frost.

Many people were killed by Soviet troops or by the severe frost.

In northern regions there is also a short growing season and severe frost during the long winter.

Occasionally, as in the winter of 1982, there is severe frost.

They turn dark and fall after the first severe frost.

There was a severe frost last night - and this is mid-August.

This both hill top and urban position means severe frosts are rare.