Lime

Growing Conditions

Growing Zones

Thrives in USDA Zones 9 - 11

Companion Planting

When to Plant

• Transplant

  Plant container-grown trees in spring after all frost risk has passed; in frost-free zones, plant in spring or early autumn

• Harvest

  Persian limes are harvested green when full-sized and slightly yielding; Key limes turn yellow when fully ripe

Organic Growing Tips

• Apply citrus-specific fertiliser three times per year - spring, early summer, and early autumn - using an organic formula with micronutrients including iron, manganese, and zinc to prevent yellowing.

• Spray diluted neem oil at dusk every 10-14 days to suppress citrus leafminer and scale; avoid spraying open flowers.

• Mulch with wood chips kept 6 inches from the trunk to retain moisture and moderate soil temperature.

• In borderline zones, wrap the trunk with frost cloth and cover the canopy during cold nights; a string of outdoor lights under the cover provides several degrees of supplemental warmth.

Common Pests

• Citrus Leafminer
• Aphids
• Scale Insects
• Spider Mites
• Citrus Canker
• Phytophthora Root Rot

Taxonomy

Kingdom

Plantae

Family

Rue family (Rutaceae)

Genus

Citrus

Species

Citrus × aurantiifolia

Natural History

The lime family encompasses several distinct species with origins in the Indo-Malay region and South Asia. Key lime (Citrus × aurantiifolia) likely originated as a hybrid in the Indian subcontinent and spread through the Middle East and North Africa with Arab traders before Spanish colonists carried it to the Americas in the 16th century. It naturalised so thoroughly in the Florida Keys that it became known as the Key lime. Persian lime (Citrus × latifolia), the seedless triploid grown commercially today, was developed in the 19th century and became dominant because it is hardier, thornless, and more productive than Key lime. The kaffir lime (Citrus hystrix), now widely called makrut lime, is a distinct species native to Southeast Asia whose leaves are more prized than its fruit in Thai and Indonesian cooking. All cultivated limes reached Europe relatively late compared to lemons and oranges, partly because their tropical origins limited their adaptable range.

Traditional Use

Lime juice and peel have deep culinary and folk-medicine traditions across South and Southeast Asia, the Caribbean, Mexico, and Latin America, with lime most prominently associated with anti-scurvy use in British naval history.

• British Naval Anti-Scurvy Use - Fruit juice

  The Royal Navy issued citrus juice to sailors from the late 18th century to prevent scurvy, a practice that produced the informal term "limey" for British sailors. James Lind's 1747 controlled experiment on HMS Salisbury sailors established citrus as the scurvy cure. Lemon was actually the primary anti-scurvy citrus used initially; lime was substituted partly for supply-chain reasons despite having lower vitamin C concentration than lemon.

• Mexican and Caribbean folk use - Fruit juice and peel

  In Mexican, Central American, and Caribbean traditions, lime is a fundamental flavouring and preservative used in ceviche (where acidity partially denatures fish proteins), agua fresca, and marinades. Folk traditions across these regions attributed digestive, fever-reducing, and antiseptic properties to lime juice, and lime-salt preparations were common home remedies for sore throats.

Lime juice is a safe food with a long culinary history. Furocoumarins in lime peel can cause phototoxic skin reactions (phytophotodermatitis) when juice contacts skin before sun exposure; rinse skin promptly after handling limes outdoors.

This information is provided for historical and educational purposes only and is not medical advice. Always consult a qualified healthcare professional before making decisions related to your health.

Morphology (Plant Structure & Identification)

• Root System

  Shallow fibrous root system highly sensitive to waterlogging and compaction; surface roots need consistent moisture but excellent drainage.

• Stem

  Small, thorny evergreen tree typically reaching 10-15 feet; Persian lime is nearly thornless compared to Key lime, which has prominent sharp spines at leaf axils.

• Leaves

  Glossy, dark green, oval leaves with characteristic winged petioles; strongly aromatic when crushed, with a clean citrus fragrance distinct from lemon.

• Flowers

  Clusters of small, intensely fragrant white flowers with pink-tinged buds; flowers multiple times per year in warm climates, with each flush followed by a fruiting period.

• Fruit

  Persian lime produces oval, seedless, thick-skinned green fruit 2-3 inches long harvested before full ripeness; Key lime produces smaller, rounder, thin-skinned fruit with many seeds and more intense juice. Both turn yellow when fully ripe.

Known Varieties

Common cultivars worth knowing

• Persian (Tahiti)

  Seedless, thick-skinned triploid hybrid; the standard supermarket lime. Hardier and more productive than Key lime, nearly thornless.

  Best for: Home orchards in zones 9-11; container growing

• Key Lime

  Small, thin-skinned, seedy, intensely flavoured; the classic Florida and Caribbean lime. More aromatic than Persian but less cold-tolerant.

  Best for: Traditional recipes and Key lime pie; zones 10-11

• Makrut (Kaffir)

  Grown primarily for its intensely aromatic double leaves rather than its thick, wrinkled fruit. A staple of Thai, Indonesian, and Cambodian cooking.

  Best for: Southeast Asian cooking; container growing in cool climates

• Rangpur

  A mandarin-lime hybrid with orange-red skin and lime-like acid flavour. Noticeably cold-tolerant for a lime type, surviving to zone 8 in sheltered conditions.

  Best for: Cooler climates where standard limes fail; marmalade and cocktails