Seeds 100 Seed (Mentha × piperita)

Peppermint (Mentha × piperita) is the boldest of the mints — a natural cross prized for its cool, intensely menthol aroma and a sharp, clean flavour that finishes with a refreshing chill on the tongue. Its dark green, slightly serrated leaves often carry a purple tint along the stems, setting it apart from the milder, sweeter spearmint. This is the classic mint for brewing fragrant tea, lifting cold drinks and chocolate desserts, and filling a home garden with one of the most recognisable scents in the herb world. As a vigorous perennial, it rewards a little care with leaves you can pick from spring right through to autumn.

Planting

Start peppermint seed indoors in spring, roughly 6 to 8 weeks before your planting-out date, and move the young plants outside once any danger of frost has passed. The seed needs light to germinate, so press it gently onto the surface of moist growing medium and do not cover it. Keep the medium moist and bright, and expect sprouts in about 10 to 14 days at 22 to 24 °C, or around two weeks at 20 °C. Choose a spot in full sun to partial shade with at least 4 to 6 hours of light a day; mint grows in sun or shade but is most productive in full sun. Set plants about 45 cm apart — or 30 to 45 cm apart in rows 45 cm apart — bearing in mind that mature plants reach 45 to 90 cm tall and spread aggressively by underground runners.

Fertilizing

Peppermint loves rich soil that is high in organic matter, so dig plenty of compost or well-rotted manure into the bed before planting; this feeds the plants and improves drainage at the same time. Aim for a soil pH of 6.0 to 6.5. In well-amended ground the plants may need no extra fertiliser at all. Where feeding is helpful, apply nitrogen from spring to early summer to match the plant's active growth. Go easy, though — too much nitrogen pushes soft, lush growth that attracts spider mites and aphids and can make disease worse.

Care

Keep the root zone consistently moist but never waterlogged, and don't let the plants wilt between waterings. Water the soil directly rather than the leaves to reduce leaf disease, watering deeply instead of giving frequent light sprinklings; drip irrigation is better than overhead sprinklers. Watch for mint rust, aphids and spider mites — the mites thrive in hot, dry conditions and where nitrogen is excessive — along with verticillium wilt, a serious soil-borne disease best avoided by using clean planting stock. Dislodge aphids and mites with a strong jet of water or insecticidal soap. Harvest runs from late spring into autumn: pick young, soft shoot tips for the most intense flavour, and cut often to keep the plant bushy. If it flowers in summer, cut the whole plant back to about 5 cm from the base to bring on fresh new growth.