PL. —Cucurbita pepo var. cylindricaBotanical illustration — drop image
Cucurbita pepo var. cylindrica

Zucchini

SpringSummerFall
3a10bHardiness 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
Background

Zucchini is the most productive plant in the summer garden — famously prolific once it gets going. The large orange-yellow blossoms, like squash flowers, are beautiful and edible. One plant will produce blossoms daily through midsummer; harvest male flowers freely (those without a tiny zucchini at the base) and you'll have a continuous supply without reducing fruit production.

The challenge is managing production: zucchini left to overgrow signals the plant to reduce flower output. Harvest every 2–3 days and keep the plant in a continuous cycle of flowering and producing small fruits.

Keep apart
Care guide
SunFull sun
WaterDeep, regular watering; consistent moisture for best production
SoilRich, well-draining, lots of compost
Spacing3–4 feet
Height24–36 inches
Zone3a – 10b
WinterAnnual — compost after first frost.
Direct sow
Seasonal tasks
spring
sowSuccession sow — sow direct or start indoors 3 weeks early for a head start, then direct sow after last frost when soil is warm; sow every ~4 weeks for a continuous supply
summer
cutHarvest male flowers in morning for use in arrangements or stuffing and frying
watchHarvest fruits every 2–3 days — overgrown zucchini shuts down flower production
sowSuccession sow — sow direct or start indoors 3 weeks early for a head start, then direct sow after last frost when soil is warm; sow every ~4 weeks for a continuous supply
watchLast sow (~13 weeks before fall frost) — production slows as nights cool; later sowings won't crop before frost
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.