Frost damage
How to recognise it
Blackened, collapsed or scorched soft growth, flowers or leaf tips appearing suddenly after a cold night, sometimes turning translucent as it thaws.
Life cycle and conditions
Occurs when tender growth is exposed to temperatures at or below freezing, particularly damaging during the last-frost risk window in spring and the first-frost onset in autumn.
Prevention
Watch forecasts around the seasonal frost risk windows and have fleece ready for vulnerable plants; site frost-tender plants away from low-lying frost pockets and early morning sun, which causes rapid, damaging thaw.
How to treat it
There's no reversing frost damage once it's happened; cut back affected growth once further frost risk has passed — the plant usually regrows from below the damage if the roots are undamaged.
Not applicable — there's no product that repairs frost damage; prevention (fleece, siting) is the only real lever.