Best Companion Plants for Squash (and What to Avoid)
Squash plants are hungry, sprawling things that take up a lot of garden real estate. The good news? Those big leaves and spreading vines actually make squash a fantastic companion for quite a few other plants. The classic "Three Sisters" planting — corn, beans, and squash together — has been used by Indigenous peoples in North America for centuries, and for good reason.
After years of growing summer and winter squash in my garden, here are the companions that consistently perform well alongside them.
Best companions for squash
| Companion Plant | Why It Works | Spacing Notes |
|---|---|---|
| Corn | Provides vertical structure; squash shades corn roots | Plant corn first, add squash 2 weeks later |
| Pole Beans | Fix nitrogen that squash craves; climb corn stalks | Sow at corn base when corn is 6 inches tall |
| Radishes | Break up soil; mature before squash needs the space | Direct sow between squash hills |
| Marigolds | Repel squash bugs and cucumber beetles | Ring around squash hills, 12 inches away |
| Nasturtiums | Trap crop for aphids; attract beneficial insects | Plant at garden edges near squash |
| Borage | Attracts pollinators squash desperately needs | One plant per 4-5 squash plants |
| Sunflowers | Attract pollinators; provide light afternoon shade | North side of squash patch |
| Peas | Early nitrogen fixers; done before squash spreads | Plant peas first in early spring |
The Three Sisters method
If you haven't tried Three Sisters planting, it's worth doing at least once. The concept is simple: corn grows tall in the center, beans climb the corn stalks and fix nitrogen in the soil, and squash sprawls at the base, shading out weeds with its large leaves and prickly stems that deter raccoons and other pests.
The key is timing. Plant corn first. When it's about 6 inches tall, plant pole beans at the base of each stalk. A week or two after that, plant squash seeds between the corn hills. If you plant everything at once, the fast-growing squash will smother the corn before it gets established.
Plants to keep away from squash
- Potatoes — compete for the same nutrients and both are heavy feeders. Potatoes can also encourage blight that affects squash.
- Fennel — inhibits growth of most garden plants including squash through allelopathic chemicals.
- Brassicas (cabbage, broccoli, cauliflower) — heavy feeders that compete with squash, and both attract similar pests.
- Melons — same family (cucurbits) so they share diseases and pests. Keep them separated by at least 20 feet.
Dealing with squash bugs naturally
The biggest pest problem with squash is, unsurprisingly, squash bugs. Companion planting helps but won't eliminate them. Marigolds and nasturtiums reduce pressure, but you'll still want to check the undersides of leaves regularly for those bronze-colored egg clusters. Scrape them off with tape. It's tedious but incredibly effective when combined with companion planting.
Dill and parsley planted nearby attract tachinid flies, which parasitize squash bugs. It's not a silver bullet, but every bit of natural pest control adds up.
Spacing considerations
Squash plants need a lot of room — 3 to 6 feet between hills depending on the variety. When planning companions, think vertically (corn, sunflowers), early (radishes, peas), or around the perimeter (marigolds, nasturtiums). Don't try to squeeze anything into the space where squash vines will eventually spread.
For the best timing on when to plant squash and its companions in your specific zone, check our planting calendar tool.
Find the best planting dates for your area → Planting Calendar Tool