Mentha requienii

Care Guide: Planting, Soil & Watering

Overview: Corsican mint is a fast-spreading but extremely low creeping herb for warm, sunny to lightly shaded spots with rich, moist, well-draining soil. It forms a fragrant carpet just a couple of centimetres tall and must never be allowed to dry out.

Quick Care Requirements

Requirement	Ideal Condition
Planting Season	Spring in zones 5b-8; spring–summer in 8-10a; spring–autumn in 10b; year-round in 11+
Growth Rate	Fast
Soil Type	Rich, organic, moist and well-draining
Water Need	Moderate to high; keep the soil consistently moist

Planting & Establishment

• Best Planting Season: Timing follows frost risk and warmth: plant in spring in zones 5b-8, in spring to summer in zones 8-10a, in spring to autumn in zone 10b, and year-round in zone 11.
• How to Plant:
  • Hole Preparation: Dig a hole a little larger than the root ball.
  • Soil Amendments: Mix plenty of organic matter such as compost into the excavated soil.
  • Planting Depth: Set the plant at the depth it grew before and cover the roots lightly, firming gently.
• Growth Speed & Expectations: Fast-spreading but ground-hugging — forms a dense mat just 1-2 cm tall that knits between paving and rocks. Keep it evenly moist and lightly shaded and it will fill a space quickly.

Soil, Watering & Drainage Care

• Soil Mix & Drainage Needs: Wants a well-ventilated, moisture-retentive mix rich in organic matter that never bakes dry; in pots use potting or peat soil with perlite or vermiculite and keep it consistently damp.
• Watering Schedule & Technique:
  • Young / Newly Planted: Water in well after planting or dividing and keep the soil moist through the first weeks so it establishes quickly.
  • Established: Water regularly so the soil stays evenly moist — mint wilts fast if it dries out and does best with generous, consistent moisture.
  • Seasonal Adjustments: More water in summer heat, less in the cool winter months.

Growing in Pots, Balconies & Indoors

Corsican mint is a tiny (1-2 cm) creeping, mat-forming mint – not a true indoor houseplant, but it grows beautifully in a wide, shallow pot and can sit on a bright windowsill that gets direct sun. On a balcony or patio it makes a fragrant living carpet.

Quick Details

• Container Size: 8-18 L (2-5 gal), the bigger the better; choose a shallow, wide pot
• Indoor Suitability: Not a deep-room houseplant; give it a windowsill with direct sun
• Best Spot: Full sun to about three-quarters sun – a little shade keeps the leaves larger and better for harvesting, while more sun means more flowers for pollinators but smaller leaves
• Soil & Drainage: Well-ventilated, free-draining, organic-rich mix – potting mix or peat with perlite or vermiculite
• Watering in Pots: Average water; keep the soil lightly moist, never soggy or stale

Indoors & On the Windowsill

• Houseplant limits: The grower notes it is not suited to growing deep indoors as a houseplant.
• Windowsill growing: It does grow on a windowsill that receives direct sun – give it the brightest sill you have.
• Overwintering: As a low, somewhat tender creeper it can be kept in its pot and moved to a sheltered, bright, frost-free spot over winter in cold climates.

On a Balcony or Patio

• Light & wind: Shallow, wide pots dry out fast, so on a sunny balcony check moisture often and keep the soil lightly moist. A touch of afternoon shade keeps the foliage lush and better for picking.

Choosing the Pot, Soil & Long-Term Care

• Pot & drainage: A shallow, wide 8-18 L pot with strong drainage holes; skip a standing-water saucer to avoid rot.
• Potting mix: Well-aerated and organic – potting mix or peat with perlite or vermiculite.
• Feeding: Feed lightly; potted plants need feeding more often than ground plants as nutrients leach with watering.

Grower’s Container Tip

• Yearly hard reduction: Each year cut back all the roots and part of the top growth to keep the clump small – this fast-spreading mint can exhaust itself and die if it is never reduced.
• Refresh the soil: Every two years replace at least part of the potting soil so it never turns stale or rotten.

Bloom & Edible Flower Guide

Quick Details

• Bloom Season: Summer (from late spring to early autumn in warmer climates)
• Flower Appearance: Tiny two-lipped (“mouth-shaped”) flowers in pale purple to white
• Edibility: Edible — like the aromatic leaves, the little flowers of this culinary mint can be eaten, and they are attractive to pollinators

Detailed Blooming Overview

Corsican mint is a ground-hugging, intensely peppermint-scented mint, and in summer its mat is dotted with minute pale-purple to white flowers. Each is only a couple of millimetres across but they are numerous, and bees and other pollinators work them eagerly.

Flower Characteristics

• Very small, two-lipped flowers in purple or white.
• Scattered across the low mat of aromatic foliage.

Bloom Care & Thinning

• Managing the bloom: A light trim keeps the mat dense; the grower recommends thinning the blossom to keep growth tidy.
• Pollination: Pollinated by bees and a good pollinator plant generally.
• Edible use: Both leaves and flowers are edible and carry the plant’s minty aroma.

Pests, Diseases & Troubleshooting

Overview: Corsican mint is a vigorous culinary mint (Lamiaceae) and, like all mints, its defining “problem” is its aggressively invasive rhizomes rather than any insect; its main biological threat is mint rust, followed by powdery mildew, verticillium wilt and the soft-bodied aphid, mite and thrips complex. Grow it contained, keep it open and un-crowded, and use soft, edible-safe controls first. Corsican mint is a tiny, ground-hugging, moss-like creeper that — unusually for a mint — is NOT invasive and is instead sensitive to drought, heat and slugs; keep it cool, moist and shaded.

Quick Troubleshooting Overview

Issue / Pest	Main Symptom	Primary Solution
Invasive rhizomes	Runners swamping the bed	Grow contained, barrier, divide
Mint rust	Orange pustules under leaves	Remove leaves, cut back, clean stock
Aphids / thrips	Colonies & scarring on new growth	Water jet, soap, sticky traps
Spider mite	Stippling on hot, dry foliage	Keep moist, raise humidity, oil
Powdery mildew / wilt	Coating or sudden wilting	Airflow, clean stock, no replant

Common Pests & Management

• Aphids (incl. Mint Aphid) (Ovatus crataegarius / Myzus persicae):
  • Symptoms: Colonies of soft green or black insects on shoot tips and leaf undersides, curling and puckering new leaves and leaving sticky honeydew; a leading nuisance on mint.
  • Prevention & Control: Blast off with a water jet; pinch out infested tips; encourage lady beetles, lacewings and hoverflies; insecticidal soap on the tips if colonies persist — favour soft controls on a culinary herb.
• Two-Spotted Spider Mite (Tetranychus urticae):
  • Symptoms: Fine pale stippling, bronzing and delicate webbing on leaf undersides in hot, dry, still conditions; foliage dulls and dries (listed in the source).
  • Prevention & Control: Raise humidity and hose down foliage; keep the soil moist, as drought-stressed mint is most at risk; encourage predatory mites; a soap or light horticultural oil spray, repeated, in bad cases.
• Thrips (order Thysanoptera):
  • Symptoms: Silvery scarring, pale flecking and tiny dark frass specks on leaves; distorted new growth (listed in the source).
  • Prevention & Control: Remove sheltering weeds; use blue sticky traps; encourage predatory mites and pirate bugs; insecticidal soap or spinosad only for heavy infestations.
• Mint Flea Beetle (Longitarsus spp.):
  • Symptoms: Tiny beetles that jump when disturbed, chewing small round shot-holes in the leaves; worst on young growth.
  • Prevention & Control: Cover young plants with fine mesh; keep beds weed-free and clear old debris where beetles overwinter; hand-pick is impractical, so rely on barriers and vigorous growth.
• Mint Root Borer & Cutworms (Fumibotys fumalis / Noctuidae):
  • Symptoms: Wilting, weak shoots and larvae tunnelling the rhizomes and roots; cutworms sever young shoots at the base.
  • Prevention & Control: Rotate and refresh plantings every few years; cultivate lightly to expose larvae to birds; remove crop debris after harvest; drench with beneficial nematodes for serious root-borer pressure.

Diseases & Fungal Issues

• Mint Rust (Puccinia menthae):
  • Symptoms: Bright orange-brown powdery pustules on leaf undersides and stems, with pale spotting above; distorted, dropping leaves — the signature and most serious disease of mint.
  • Treatment & Management: Remove and destroy affected leaves and stems; improve airflow and avoid overhead watering; cut plants right back and clear all debris in the off-season; badly infected plantings are best dug out and restarted with clean stock elsewhere, as rust persists in the rhizomes; a sulfur fungicide can help protect new growth.
• Powdery Mildew (Golovinomyces / Erysiphe spp.):
  • Symptoms: White powdery coating on leaves in crowded, humid or shaded conditions.
  • Treatment & Management: Thin and space plants for airflow; give sun; water at the base; cut back congested growth; a potassium-bicarbonate, milk or sulfur spray for stubborn cases.
• Verticillium Wilt (Verticillium dahliae):
  • Symptoms: Sudden wilting, yellowing and stunting of shoots from a soil-borne fungus; a serious disease of commercial mint with no cure once established.
  • Treatment & Management: Plant only clean, disease-free stock; do not replant mint where wilt has occurred; rotate sites and remove and destroy affected plants; keep plants unstressed with even moisture.
• Anthracnose / Leaf Spot (Sphaceloma menthae):
  • Symptoms: Sunken tan spots with dark margins on leaves and stems, sometimes girdling shoots (“mint anthracnose” or leopard spot) in wet weather.
  • Treatment & Management: Improve airflow and avoid wetting foliage; remove affected growth and debris; cut back and clean up in the off-season.
• Root Rot (Pythium / Phytophthora spp.):
  • Symptoms: Yellowing, wilting and collapse with dark rotted roots in soggy, poorly drained soil.
  • Treatment & Management: Provide good drainage and avoid waterlogging (except for water mint, which tolerates wet feet); do not overwater containers.

Growing Difficulties & Abiotic Problems

• Aggressive, Invasive Rhizomes:
  • Cause & Symptoms: Mint’s fast-spreading underground runners quickly colonise beds and swamp neighbours — the source flags every species as aggressive; this is mint’s number-one “problem.”
  • Correction Strategy: Grow in containers or sink a bottomless pot or root barrier into the ground; harvest and divide regularly; chop back wandering runners to keep it in bounds.
• Drought & Heat Sensitivity (not invasive):
  • Cause & Symptoms: Unlike other mints, this miniature creeper is not aggressive; instead it browns, thins and dies out in heat, drought or full sun, and is grazed by slugs.
  • Correction Strategy: Grow in cool, moist, part-shaded soil between pavers; never let it dry out; protect the tender mat from slugs and hard frost.
• Rust & Disease from Crowding:
  • Cause & Symptoms: Dense, congested clumps trap humidity and invite rust and mildew.
  • Correction Strategy: Thin and divide clumps regularly, cut plants back hard through the season for fresh clean growth, and give them air and light.
• Leggy, Sparse Growth in Low Light:
  • Cause & Symptoms: Thin, floppy, poorly-flavoured stems in shade or after flowering.
  • Correction Strategy: Grow in good light; pinch tips to bush out; shear plants back after flowering to force tender new foliage.
• Iron Chlorosis:
  • Cause & Symptoms: Yellowing between the veins of young leaves in very alkaline soils.
  • Correction Strategy: Improve organic matter and, if needed, apply chelated iron; keep soil evenly moist.

What Helps — Products & Tools

For culinary mint use soft, edible-safe options: insecticidal soap for aphids and thrips, horticultural oil for spider mite, beneficial nematodes for root borer, fine mesh against flea beetle, blue/yellow sticky traps, and sulfur or potassium-bicarbonate sprays for rust and mildew — all backed by containment, division and hard cut-backs. The single best control is clean stock and good hygiene against rust and wilt.