Lemon tree in the ground before a freeze

A low of 32°F is forecast. Lemon flowers and young fruit can be killed at about 29°F, and full-size fruit can be damaged at 28–31°F. Leaves can be a few degrees colder than the air on clear, calm nights, and young trees are the most at risk.

When we suggest this

• ForecastA night at or below about 32°F is forecast for tonight or the next 2 nights.
• Your noteYour note: it grows in the ground.

What would stop us suggesting it

• The morning after the forecast night passes (or when a fresh forecast no longer shows it).
• When you mark it Done or Doesn't apply. "Doesn't fit my setup" stops it for that plant this season.

What to do

1. Pick lemons that have reached full size; they keep well indoors. Leave small fruit on the tree.
2. If the tree is young or small, cover the whole tree in the late afternoon with a frost cloth or blanket that reaches the ground. Don't tie it around the trunk, and keep plastic off the leaves.
3. If the soil under the tree is dry, water it during the day. Bare, moist soil gives off more heat at night.
4. Take the cover off the next morning, once it's above freezing.

What we can't know

• How cold it gets at your tree. Spots near a sunny wall stay warmer; low spots run colder.
• How long the cold lasts. A short dip does less harm than several hours.

UF/IFAS gives flowers and young fruit killed at about 29°F, mature fruit damaged at 28–31°F, leaf drop at 22–24°F, and severe wood damage at about 20°F. Arizona Extension says lemons suffer some damage below about 25°F, and Texas A&M says the high 20s kill or badly damage lemons and freeze fruit over several hours. Meyer lemon is hardier (about 20–22°F for mature trees, UF and UC). Duration and hardening matter: hardened tissue can tolerate 5–6°F more cold. We use 32°F because leaves and fruit can run 3–4°F below air temperature on clear, calm nights and young trees are less hardy.

Where this advice applies

All US regions.

Gardens where lemons grow in the ground and nights can reach freezing, mostly USDA zones 9 and 10.

Trees against a sunny wall and on slopes stay a few degrees warmer; low spots and lawns run colder. Meyer lemon handles cold somewhat better than 'Eureka' or 'Lisbon'.

Exceptions

• Lemons in containers (see the container task).
• Trees you've marked removed.

Related guide sections

• Growing lemon trees: cold

Reviewed

Sources checked Sept 2026 · awaiting expert review

Gardenplanner research (AI-assisted), pending extension-qualified review

Rule id and version: lemon.freeze-protect@1