Lemon tree.

At a glance

Care level

Moderate

Plant type

Fruiting Tree

Light

Full sun

Indoor light

direct

Water

Every 7 to 14 days

Mature size

Up to 15 feet tall and 10 feet wide

Growth rate

medium

Hardiness

USDA 9 to 11

Bloom time

Spring to Summer

Care

Lemon trees need plenty of sunlight and well-draining soil. Water thoroughly when the top inch of soil feels dry, and protect them from frost. Prune to maintain shape and encourage fruit production.

Watering

Water deeply when the top inch of soil is dry; reduce watering in cooler months.

Feeding

Feed with a balanced citrus fertilizer during the growing season (spring through fall).

Pruning

Prune lightly after fruiting to shape the tree and remove dead or crossing branches.

Repotting

Repot every 1-2 years into a slightly larger container when rootbound.

Soil

Well-draining, slightly acidic potting mix

Soil pH

5.5 to 6.5

Temperature

10 to 30°C

Humidity

50 to 60%

Drought tolerance

moderate

Lifespan

Perennial, can live for 50 to 100+ years

Fragrance

strong

Deer and rabbits

low

Safety

People

The fruit, leaves, and peel are generally considered safe for human consumption in typical amounts, though excessive consumption of acidic fruit can cause digestive upset.

Pets

The fruit and leaves are non-toxic to cats and dogs, but ingestion of large quantities may cause mild stomach upset.

Children

Small children might be tempted to eat unripe fruit or chew on leaves, which can cause mild stomach upset due to acidity or essential oils.

Contact allergens

The essential oils in the peel can cause skin irritation or photosensitivity in some individuals.

Airborne allergens

Pollen can be a mild allergen for sensitive individuals.

Edibility

While the fruit is edible, this plant is primarily grown for ornamental and culinary purposes, not for wild foraging.

How to identify it

• Glossy, dark green leaves
• Sharp, woody thorns
• Fragrant white flowers
• Oval, yellow fruit
• Citrus scent when bruised

Height

1.8 to 4.5m

Spread

0.9 to 3m

Leaves

Green, evergreen

Flowers

White, 2 to 3cm

Fruit

Yellow, Winter to Spring

Common problems

• Aphids — Small, pear-shaped insects that feed on new growth, causing distorted leaves and sticky honeydew.
• Scale insects — Small, immobile insects that attach to stems and leaves, sucking sap and weakening the plant.
• Citrus greening (HLB) — A serious bacterial disease transmitted by insects, causing yellowing leaves, fruit drop, and bitter fruit.
• Sooty mold — A black fungus that grows on honeydew excreted by sap-sucking insects, hindering photosynthesis.
• Nutrient deficiency — Yellowing leaves (chlorosis) can indicate a lack of essential nutrients like nitrogen or iron.

Growing it

Propagation

Cuttings, Grafting

When to plant

Spring, Summer

Overwintering

In colder climates, bring container-grown lemon trees indoors before the first frost. Place in a sunny window and reduce watering, but do not let the soil dry out completely. Protect from drafts and ensure good air circulation to prevent fungal issues.

In containers

Excellent for containers, especially dwarf varieties. Use a pot at least 15-20 gallons for mature trees, with excellent drainage.

Plant companions that enjoy similar well-drained soil and full sun, and avoid those known to be overly aggressive spreaders.

Grows well with

• Rosemary — Rosemary can help deter certain pests that bother citrus trees and enjoys similar sunny, well-drained conditions.
• Marigolds — Marigolds are known to repel nematodes in the soil, which can be beneficial for citrus roots.
• Lavender — Lavender attracts pollinators and its fragrance may help deter some pests, while preferring similar well-drained soil.

Keep away from

• Mint — Mint can be very invasive and aggressively spread its roots, potentially outcompeting the citrus tree for resources.
• Fennel — Fennel is known to inhibit the growth of many other plants, including citrus, and is best planted away from them.

Similar species

• Lime — Limes are closely related citrus fruits with similar growth habits and care requirements, though they often have more thorns.
• Orange — Oranges share many similarities in terms of climate needs and general care, but typically produce larger, rounder fruit.
• Grapefruit — Grapefruits are another large citrus fruit that requires similar growing conditions to lemons but can grow into larger trees.

Science

Family

Rutaceae

Genus

Citrus

Order

Sapindales

Class

Magnoliopsida

Native range

Native to South Asia, likely Northeast India.

Conservation

Not of conservation concern.

In its native habitat, Citrus limon thrives in subtropical climates with well-drained soil and ample sunlight.

Value to wildlife

nectar source, larval host plant

Pollinators

bees, butterflies, moths

Uses

ornamental, culinary, fragrance

Taxonomy resolved against GBIF.

Questions people ask

How much sun does a lemon tree need?

Lemon trees need at least 6 to 8 hours of direct sunlight per day to thrive and produce fruit.

How often should I water my lemon tree?

Water thoroughly when the top inch or two of soil feels dry, ensuring good drainage to prevent root rot.

Can I grow a lemon tree indoors?

Yes, dwarf varieties can be grown indoors in pots, provided they receive adequate light and humidity.

When do lemon trees bloom?

Lemon trees can bloom and produce fruit multiple times a year, often with a main flush in spring.

Why are my lemon leaves turning yellow?

Yellowing leaves can be caused by overwatering, underwatering, nutrient deficiencies, or pests.

Where the name comes from

The scientific name 'Citrus limon' comes from the Latin word 'citrus' for the fruit and 'limon' which is believed to be of Semitic origin, eventually leading to the common name 'lemon'.

Good to know

• The word 'lemon' likely comes from the Malay word 'limau'.
• Lemons contain more sugar than limes.
• The Eureka lemon variety is one of the most common types found in grocery stores.
• Lemon trees can live for many decades, sometimes over 100 years.