I lost three potted plants to the first frost last year. Woke up one morning, and my favorite geraniums were brown mush. My neighbor across the street, who keeps flowers blooming on her porch into December, finally told me her secret. It is not a fancy greenhouse. It is timing.

Frost kills plants when ice crystals form inside the leaves and burst the cells. The goal is to keep the leaves above freezing overnight.

Bring Pots Inside When You Can

The easiest fix is also the most obvious. Potted plants can come inside. A garage, a basement, or even a laundry room works for a night or two. I shuffle my pots into the mudroom when the forecast says frost, and it has saved every single one.

Do not bring them into a heated room and leave them there for weeks, that shocks them in a different way. A cool, bright spot is ideal.

Cover Them the Right Way

When you cannot move them, cover them. But the fabric matters. Use a cloth sheet, blanket, or frost cloth, never plastic. Plastic traps condensation against the leaves, and the moisture freezes and does more damage than the frost would have.

Drape the cover so it reaches the ground, which traps the heat rising from the soil. Secure it with bricks or rocks so the wind does not rip it off at 3 a.m.

Water Before the Cold Night

This one sounds backwards, but moist soil holds heat better than dry soil. Give the pots a good soak in the afternoon before a frosty night. Wet soil releases heat slowly overnight, which can keep the roots a few degrees warmer.

Do not water in the evening if the temperature will drop fast. You want the water absorbed and the leaves dry before dark, because wet leaves freeze quicker.