What To Plant
After Onions

The Best Crops To Plant After Onions

(The Quick Answer)

Onions, like their garlic kin, are light feeders, leaving the soil’s pantry still well-stocked.

This makes room for tomatoes, peppers, beans, brassicas, or even cucumbers and squash if your growing season still has months to give.

Avoid: Other alliums (garlic, leeks, shallots). They share soil-borne diseases like white rot that linger far longer than you’d want.

Why These Work

Onions spend months in the soil but don’t take as much from it as heavy feeders.

They also don’t share many pests or diseases with most other crop families, making their beds safe for a broad rotation.

A quick switch to another plant family not only breaks disease cycles but also ensures that your garden space works hard for you year-round.

Not sure which crop is right for following after your onions?

Let’s look more closely at the best options, why they work, and how to know when each one is the right choice.

Seeds are promises for the future, neatly tucked into paper.

Best Options to Grow After Onions

(The Detailed Answers)

Beans (or Peas in cool shoulder seasons)

Why it works: Legumes are the soil’s quiet philanthropists, pulling nitrogen from thin air and tucking it back into the ground. They break the nightshade disease cycle and leave the soil richer than they found it.

Best when: You’ve got 50–60 frost-free days left, and the soil drains well enough for quick root establishment.

Consider: Inoculate seed for better nodulation, pick often, and don’t be surprised if the beans arrive in generous handfuls you didn’t see coming.

Tomatoes (or Peppers in warm climates)

Why it works: Heavy feeders thrive in the nutrient-rich soil left behind; the allium family shares few diseases with nightshades.

Best when: Garlic is harvested in early to mid-summer, giving tomatoes/peppers enough time to set fruit.

Consider: Choose determinate tomato varieties for shorter seasons; give peppers the warmest, sunniest bed.

Fall Brassicas (Broccoli, Cabbage, Kale)

Why it works: Brassicas drink deeply from the fertile soil left behind, and they’re happy to race the shortening days.

Best when: You can transplant starts 6–10 weeks before frost; they’re cool-weather creatures who sweeten with a touch of chill.

Consider: Netting will deter the cabbage moth’s children; steady water keeps them tender.

Cucumbers or Zucchini

Why it works: These cucurbits are heavy feeders but quick growers, perfect for a fertile bed in mid-summer.

Best when: At least 50–60 frost-free days remain; choose compact or quick-maturing varieties.

Consider: Mulch heavily to keep soil moisture steady.

Cover Crops (Oats + Peas, or Winter Rye + Hairy Vetch)

Why it works: When it’s too late for another “main event,” a cover crop dresses the soil in green over winter, feeding the underground life while protecting against erosion.

Best when: You’ve run out of growing season but want spring-ready soil.

Consider: Know your chosen mix’s temperament - oats die back with frost for easy spring prep, rye demands a formal ending with a crimp or cut.

More Unusual Companions

Sweet Corn (Late Planting): In long-season climates, a quick corn run can follow onions, but only when there's enough frost-free days ahead.

Fennel: Will bolt in summer heat but does beautifully from midsummer sowings in cooler zones.

What to Avoid After Onions (and Why)

Other Long-Season Alliums:

They tie up the bed for too long and don’t break disease cycles.

Garlic,
Leeks & Shallots:

They share the same family tree and with it, the same disease baggage and pest invitations.

Bed Reset & Prep

✅ Lift onions carefully; remove debris and any yellowing leaves from the bed.

✅ Compost healthy plant material and burn any with disease.

✅ Loosen the soil gently, keeping structure intact.

✅ Spread ½–1 inch compost; re-level.

✅ Mulch if planting a fall crop; water in deeply.

Growing food is more than just growing food.

It’s partnership. A quiet rhythm shared between you, the plants, and the soil, deepening with each season.

All About Timing Cheatsheet

If it's:

Mid Summer: Plant tomatoes, peppers, beans, zucchini, or cucumbers.

Early Fall: Sow fall brassicas or a cover crop oats/peas or rye/vetch and close the curtain for winter.

Cool climates: Go for brassicas or overwintering cover crops.

Warm climates: Follow with heat-loving fruiting crops, then a late brassica run.

The seed remembers the hand that sowed it.

Go Forth & Grow...

Onions hold layers of patience and persistence, ripening quietly beneath their green tops.

They remind us that what looks humble on the outside can be full of depth within.

Whether you grew a basket or just a bundle, your onions tell the tale of steady tending.

This onion guide was just the beginning. Follow its path toward the crops that come after, keeping the cycle fresh and the soil alive.

Layer by layer, keep growing.

This guide was created with dirt under my fingernails, late nights, and a lot of care. No ads, no paywalls, just a simple offering for fellow growers.

If it helped you, inspired you, or made crop rotation feel just a LITTLE less mysterious (or even just if you enjoyed your ads-free time) there are two simple ways to say thanks:

Share the Love... Sow it Forward!

Share it with someone who might be interested in it.

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Created by Bethany Archer, lifelong gardener and founder of Grow & Gather Life.