Planting and Growing Mint in Cold-Climate Gardens

Mint brings bright, cooling flavor for tea, salads, sauces, and desserts. Spearmint is sweet and gentle, while peppermint is bold and menthol-rich. Leaves add vitamins A and K and refreshing aroma oils. Mint loves cool weather and steady moisture, so it thrives in short, mild summers. With a bit of containment and regular picking, it provides baskets of fresh growth from spring to frost. This guide explains how to grow mint in cold climates with clear steps, cold-hardy mint tips, and simple northern gardening advice.

Mint Varieties Suitable for Cold Climates

  • Spearmint (Mentha spicata)—very hardy and productive; classic flavor for cooking and drinks.
  • Peppermint (Mentha × piperita, e.g., ‘Black Mitcham’)—strong menthol taste for tea; vigorous in cool summers.
  • ‘Kentucky Colonel’—large-leaf spearmint type; robust growth and great for mojitos and iced tea.
  • Apple Mint (Mentha suaveolens)—soft, fruity leaves; hardy in many cold gardens when mulched.
  • ‘Moroccan’ Mint—bright, sweet spearmint for tea; reliable in cool, moist beds and containers.

Soil & Site Considerations for Mint

  • Mint grows in full sun to partial shade; 4–6 hours of sun is enough in northern gardens.
  • Moist, well-drained loam rich in organic matter suits mint best.
  • Target pH 6.0–7.5; tolerate slightly acidic to neutral soils.
  • Prepare beds with 3–5 cm (1–2 in) of compost mixed into the top 15–20 cm (6–8 in).
  • Use raised beds or large containers to control spread and improve drainage in wet springs.

Planting and Spacing Mint in Cold Regions

  • Transplant after hard frosts pass and soil is workable; roots establish in cool soil (10–18 °C / 50–65 °F).
  • Set crowns or potted plants at the same depth they grew in containers.
  • Space 30–45 cm (12–18 in) apart in rows 45–60 cm (18–24 in) apart; closer in containers for quick fill.
  • Sow seed 0.5 cm (¼ in) deep indoors 6–8 weeks before last frost; many gardeners prefer divisions or cuttings for true-to-type flavor.
  • Contain rhizomes with bottomless pots or root barriers sunk 20–30 cm (8–12 in) into the soil.
  • Pinch tips early and often to keep plants low, leafy, and tender.

Companion Plants for Mint

  • Good neighbors: cabbage family, peas, lettuce, and carrots—mint’s scent can confuse some pests and fills edges as living mulch.
  • Flowers like calendula, borage, and yarrow bring pollinators that also visit mint blooms.
  • Avoid close planting with cucumbers and melons if space is tight; mint can shade and compete for moisture.
  • Keep mint out of permanent herb beds with delicate perennials unless contained, as rhizomes spread quickly.

Watering & Fertilizing Mint

  • Provide 2.5–3.5 cm (1–1.4 in) of water per week; steady moisture keeps leaves tender and aromatic.
  • Mulch 3–5 cm (1–2 in) with straw or leaf mold to hold moisture and moderate soil temperature.
  • Feed lightly in spring with compost or a balanced organic fertilizer (e.g., 4-4-4) at label rates.
  • Side-dress midseason if leaves pale; avoid heavy nitrogen that reduces essential oil concentration.

Extending the Season for Mint

  • Row cover or cold frames wake plants earlier in spring and protect new shoots from late frost.
  • Overwinter containers in an unheated garage or against a sheltered wall; water sparingly to keep roots just moist.
  • Cut and dry bunches before first hard frost for winter tea; also freeze chopped leaves in ice cubes.
  • In very cold zones, mulch crowns after the ground freezes to prevent heaving.

Mint Crop Calendar

  • High-Latitude: set divisions late May–June; first flush harvest June–July; repeat cuts through August; dry or freeze before September frosts.
  • Boreal: plant late May; harvest June–September with 2–4 cuts; divide clumps in spring or early autumn.
  • Cool-Temperate: plant April–May; harvest May–October; divide spring or early autumn for vigorous regrowth.

Mistakes to Avoid When Growing Mint

  • Letting mint run free without barriers—rhizomes spread fast.
  • Underwatering in mid-summer; stress makes leaves coarse and less flavorful.
  • Overfeeding with high nitrogen, which dilutes oils and taste.
  • Allowing tall flowering stems to dominate; regular pinching keeps leaves tender.
  • Planting in deep shade where growth is thin and prone to disease in cool, damp weather.

Sustainability Checklist

  • Grow in containers or bounded beds to protect nearby plants and maintain biodiversity.
  • Water with drip or soaker hoses and mulch to save water.
  • Feed soil with compost and avoid peat-heavy mixes when possible.
  • Leave some blooms for pollinators while keeping a portion pinched for best leaf quality.
  • Share divisions of hardy local strains to build resilient community seed and plant stock.