Cold hardiness & minimum temperature

Is Lemon tree (Citrus limon)cold hardy? Hardiness zone & min temp

Also called Meyer lemon, Eureka lemon, Lisbon lemon.

About Lemon tree

Citrus limon · also called Meyer lemon, Eureka lemon · edible

Lemons are evergreen citrus trees from Asia, grown in the ground in frost-free climates and in pots elsewhere. Meyer lemon is the most forgiving for cool-climate container culture; Eureka and Lisbon are standard for outdoor groves. Toxic to pets, especially the foliage and rind.

The lemon (Citrus limon) is an evergreen citrus widely grown as a container plant in cool-temperate climates because it is frost-sensitive, with some cultivars tolerating only brief dips toward roughly 5 C (about 42 F).

Use a large container (around a 15-gallon / ~17 in pot) with drainage holes; protect or cover and water the tree before frost, as exposure near or below about -1 C (30 F) damages foliage and fruit.

Cold limit: USDA 9-11 outdoors; potted elsewhere · RHS H2 (13-29°C)

Watch for — Leaf drop after a move: Citrus dislikes sudden change in light or temperature; allow 3-4 weeks to acclimate.

Sources: rhs.org.uk, ucanr.edu, ucanr.edu

What lemon tree's hardiness rating actually means

Lemon tree is a tender fruiting plant, not a hardy one. It crops outdoors only in roughly USDA 9-11 outdoors; potted elsewhere; in cooler zones it is a container plant moved under cover for winter. Its RHS rating of H2 means: Tender — survives a frost-free greenhouse or a very mild, sheltered spot. On the US scale that maps to USDA 9-11 outdoors; potted elsewhere — the zones where it can be left outdoors year-round.

New to these scales? The USDA hardiness zone map explained covers how the zone numbers work, and you can find your own zone with the zone finder.

Minimum temperature — and what happens below it

Minimum survivable temperature is roughly about 1 to 5 °C — tolerates cold but no real frost. Lemon tree fruits in warmth and is set back or killed by frost.

Concretely, for lemon tree as it gets too cold:

Below about 1 to 5 °C — tolerates cold but no real frost the foliage and any fruit are damaged; a hard frost can kill the whole plant.
A light frost typically scorches leaves and ruins the current crop even when the framework survives.
Roots in a container freeze far faster than roots in the ground, so potted specimens need earlier protection.

Can lemon tree go outside or overwinter — and where?

It can stay outdoors year-round only in USDA 9-11 outdoors; potted elsewhere; in a UK or cold-US climate it is a conservatory or move-it-indoors plant for winter.
Summer it outside in full sun for the best crop, then bring it into a cool, bright, frost-free room before the first frost.
A bright unheated (but frost-free) glasshouse or porch is the ideal overwintering spot — cool and dormant, never freezing.

Work back from your local frost dates with the frost-date calculator: the last spring frost and first autumn frost are what really decide when lemon tree can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H2 figure above.

Frost protection for borderline lemon tree

Lemon tree is right on a hardiness edge in many gardens, so if you are pushing it, these measures buy it the margin it needs:

Move containers into a frost-free glasshouse, porch or cool room before the first forecast frost.
For borderline-zone ground plants, wrap the trunk and fleece the canopy, and mulch the root zone heavily.
Keep it on the dry side over winter — cold plus wet roots is what actually kills tender fruit.

Lemon tree hardiness — frequently asked questions

Is lemon tree cold hardy?

Lemon tree is a tender fruiting plant, not a hardy one. It crops outdoors only in roughly USDA 9-11 outdoors; potted elsewhere; in cooler zones it is a container plant moved under cover for winter. Frost-tender. Grow lemon tree in the ground only within USDA 9-11 outdoors; potted elsewhere; everywhere colder it lives in a large pot that comes into a frost-free space each winter.

What is the minimum temperature lemon tree can survive?

Minimum survivable temperature is roughly about 1 to 5 °C — tolerates cold but no real frost. Lemon tree fruits in warmth and is set back or killed by frost.

What hardiness zone is lemon tree?

Lemon tree is rated USDA 9-11 outdoors; potted elsewhere and RHS H2 — Tender — survives a frost-free greenhouse or a very mild, sheltered spot.

Can lemon tree survive winter outside?

It can stay outdoors year-round only in USDA 9-11 outdoors; potted elsewhere; in a UK or cold-US climate it is a conservatory or move-it-indoors plant for winter. Summer it outside in full sun for the best crop, then bring it into a cool, bright, frost-free room before the first frost. A bright unheated (but frost-free) glasshouse or porch is the ideal overwintering spot — cool and dormant, never freezing.

How do I protect lemon tree from frost?

Move containers into a frost-free glasshouse, porch or cool room before the first forecast frost. For borderline-zone ground plants, wrap the trunk and fleece the canopy, and mulch the root zone heavily. Keep it on the dry side over winter — cold plus wet roots is what actually kills tender fruit.