Spearmint

SpringSummerFallInvasive

3a–11bHardiness zone

Peak bloom windowZone 6b · frost-offset weeks

Winter

Not in bloom

Spring

Peak bloom

Summer

Peak bloom

Fall

Not in bloom

Peak bloom

In bloom

Peak bloom windowZone 6b · frost-offset weeks

Winter

Not in bloom

Spring

Peak bloom

Summer

Peak bloom

Fall

Not in bloom

Peak bloom

In bloom

Background

Spearmint is the mint of mojitos, mint sauce, and tabbouleh — lighter and sweeter than peppermint, with a clean cool flavour that doesn't overpower. It is aggressively invasive; plant only in buried containers, raised beds with solid sides, or between hard surfaces. A forgotten corner of mints can colonise half a garden bed in a single season.

Harvest regularly to keep plants from flowering — once they set seed the flavour declines. Cut back to 2 inches after the first flush to encourage a second. Divide in spring or autumn; runners are easily potted up.

Good companions

Brassica oleracea var. italica Brassica oleracea var. palmifolia Fragaria × ananassa Solanum lycopersicum Brassica oleracea var. capitata

Keep apart

Matricaria chamomilla Petroselinum crispum

Care guide

SunFull sun to partial shade

WaterRegular; prefers consistent moisture

SoilRich, moist, well-draining

SpacingPlant in containers or with deep root barriers — spreads by underground runners

Height12–24 inches

Zone3a – 11b

Frost hardyInvasive

Seasonal tasks

spring

watchAlways plant in containers or with deep root barriers — spreads aggressively by underground runners

summer

cutHarvest stems before flowering; pinch flower heads as they appear to maintain leaf quality

Common problems

Powdery mildew

Symptoms

White or grey powdery coating on leaves — usually starting on older growth in humid conditions or when nights cool.

Treatment

Improve air circulation by thinning plants. Apply neem oil or potassium bicarbonate spray at first sign. Avoid overhead watering.