Citrus hystrix – Makrut lime

Citrus hystrix – Makrut Lime

Citrus hystrix, the makrut lime, is an evergreen citrus with glossy leaves that look double-lobed because each leaf has a broad, winged stalk below the blade. The leaves and rough green rind contain strong aromatic oils and are used in Southeast Asian cooking.

A makrut lime plant needs warmth, strong light and a chunky free-draining potting mix. In a pot, it grows as a branching citrus shrub or small tree. Pick single mature leaves only from established plants grown for cooking use.

Double-lobed leaves and rough green fruit

• Leaves: Glossy citrus-scented leaves that look like two joined leaf sections because the leaf stalk is broad and winged.
• Fruit: Rough, wrinkled green fruit with an oil-rich rind.
• Flowers: Fragrant white flowers on mature plants under warm, bright conditions.
• Growth: Thorny evergreen shrub or small tree; container size and pruning keep it smaller in a pot.
• Use: Aromatic leaves and rind are valued in cooking. Harvest for cooking only from plants grown for edible use.

Where makrut lime comes from

Citrus hystrix is a citrus species in the Rutaceae family. This citrus comes from parts of the eastern Himalaya and southern China, with Wallis Island also part of its range.

Thorny stems carry the paired-looking leaves, and mature plants can also produce bumpy green fruit. Growth is faster in warmth and full light, then slows when days become darker and cooler. Young plants need most of their leaves for growth; harvest regularly only once the crown is fuller.

Makrut lime care and leaf harvest

• Light: Makrut lime needs as much light as you can give it. Direct sun is suitable after gradual acclimation from indoor or winter conditions.
• Water: Water deeply after the upper part of the potting mix has dried. When growth slows in winter, wait longer between waterings.
• Substrate: Use a chunky citrus mix with mineral particles and good drainage. A chunky mix helps keep air around the roots, especially in cool conditions.
• Temperature: Keep warm and frost-free. Warmth and free drainage help new growth return after winter.
• Humidity: Hot dry air can stress the leaves and encourage spider mites. In very dry indoor air, a humidifier helps reduce leaf stress.
• Feeding: Feed while the plant is growing with a citrus fertiliser that includes magnesium, iron and other trace nutrients. This helps prevent weak, pale new leaves.
• Leaf harvest: Take individual mature leaves from a healthy established plant. Removing too many leaves slows regrowth.
• Pruning: Prune lightly to keep the crown balanced. Wear gloves because mature stems can be thorny.
• Seasonal move: Move outdoors only after nights are stable, then bring the plant back under cover before autumn cold.

Leaf shed, dry edges and hidden pests

• Leaf shed under cover: Check for lower light, dry air, cold draughts and a wet rootball. Move it to better light, keep it out of cold draughts and make sure the pot drains properly.
• Pale extension growth: Review light, feeding, iron and potting mix condition. Container citrus can show pale growth when fertiliser is missing or the mix is depleted.
• Dry leaf edges: Check heat, watering gaps and very dry air. Makrut lime leaves can mark when the plant dries too far between waterings.
• Sticky leaf joints: Inspect stems, petiole bases and leaf undersides for scale or mealybug. Dense branching can hide pests close to the stem.
• Slow spring growth: Check root temperature, potting mix condition and pot size. Cold, compacted or exhausted mix delays new growth.

Thorny stems and aromatic oils

Leaves, peel and stems contain aromatic oils and psoralens. Keep leaves, fallen fruit and pruned stems away from pets, and wear gloves when pruning, harvesting or repotting if the stems are thorny or your skin is sensitive.

The species name hystrix means bristly or porcupine-like, fitting the rough fruit and thorny growth.