Harvest guide

Sweet corn harvest guide: when to pick and how much to expect

Sweet corn has a short window of perfect ripeness, and its sugars start turning to starch right after picking. Here is the simple test for ripe ears and what a row gives.

Days to harvest: 65–80 days from sowing(Montana State University Extension)
Harvest months: August–October(RHS)
Typical yield: 10 ears per 3 m (10 ft) row(Montana State University Extension)
Spacing: 34–45 cm (13–18 in) apart(RHS)
Family: Poaceae (grass family)
Botanical name: Zea mays

Sweet corn planting and harvest calendar

Sow April–June. Harvest August–October.(RHS)

Sweet corn season timeline

Sow
Harvest

Months are for a temperate Northern Hemisphere climate, based on RHS (UK) guidance. Shift them earlier or later to match your own frost dates, or by about six months in the Southern Hemisphere.

Sow
Harvest

When to harvest sweet corn

Check once the silks at the tip of the ear turn brown. Peel back a little husk and press a kernel with your thumbnail.(RHS)
Watery juice means not yet, creamy or milky juice means ready, and a doughy paste means it's past its best.(RHS)

How often to pick

Ears usually start ripening in late summer. Once the silks brown, test each ear, then twist ripe ones and pull them sharply off the stem.(RHS)

How many sweet corn to expect

A 3 m (10 ft) row typically gives about 10 ears.(Montana State University Extension)

Yields vary with variety, weather, soil and care. Treat these as ballpark figures, not targets.

Plan for your family

For 4 people eating sweet corn fresh, plan on about 18–30 m (60–100 ft) of row(University of Missouri Extension). That should give roughly 60–100 ears(Montana State University Extension).

To preserve or store some as well, allow 9.1–15.2 m (30–50 ft) of row per person.(University of Missouri Extension)

See the full planting-per-person guide →

Storing your sweet corn

Eat it as soon as possible. Sweetness drops quickly after picking as sugars turn to starch.(RHS)
If you must store it, keep it cold and humid. Expect about five days at most.(University of Minnesota Extension)

Track it

Log every sweet corn harvest

Harvest Journal is a private garden journal for your phone. Tap to log each picking of sweet corn by weight or count, and see your season add up, with no account needed.

Prefer paper? Make a free harvest report PDF in your browser, with no account needed.

Sweet corn harvest FAQ

How do I know when sweet corn is ripe?

Wait until the silks turn brown, then peel back the husk and pierce a kernel. Milky juice means it's ready. Clear juice means it needs longer, and paste means it's overripe.