Companion Planting Chart: What to Plant Together (Full Vegetable Guide)

The idea behind companion planting is simple: some plants just grow better next to each other. Put the right neighbors together and you can cut down on pests, pull in more pollinators, and fit more into the same bed. Put the wrong ones together and they fight over the same food and the same space. Here is a plain guide to what belongs next to what, why it works, and a few classic pairings worth copying into your own garden.

How to use a companion planting chart

Think of the chart as a starting point, not a rulebook. Some pairings are backed by research, like beans feeding the soil for their neighbors, or marigolds knocking back root-knot nematodes. Others are garden tradition that has held up over generations. Good companions share space, timing, or a pest-fighting habit without competing. Plants to keep apart crowd the same roots, draw the same pests, or simply slow each other down. Try the pairings, watch your own beds, and keep what works for you.

Crop	Good companions	Keep apart from
Tomato	Basil, marigold, carrots, onions, nasturtium	Cabbage family, fennel, corn
Pepper	Basil, onions, carrots, tomatoes	Fennel
Carrot	Onions, leeks, lettuce, radish	Dill, fennel
Onion and garlic	Carrots, beets, lettuce, cabbage	Beans, peas
Beans and peas	Corn, squash, carrots, cucumber	Onions, garlic, fennel
Corn	Beans, squash, cucumber	Tomatoes
Squash and pumpkin	Corn, beans, nasturtium, radish	Potatoes
Cucumber	Beans, corn, radish, dill	Sage
Lettuce	Carrots, radish, onions, beets	Few conflicts
Cabbage and broccoli	Onions, beets, dill, marigold	Tomatoes, beans, strawberries

Why good pairings work

Most helpful pairings earn their spot in one of four ways: they confuse pests, feed helpful insects, share nutrients, or stack up in space. Knowing the reason lets you adapt the chart to your own garden instead of following it blindly.

Hiding plants from pests

Strong smells throw pests off the scent. A row of onions or chives near your carrots helps cover the smell that carrot rust flies hunt for, and aromatic herbs like basil muddy the trail around tomatoes. Marigolds do something extra underground: French marigolds knock back root-knot nematodes in the soil, which is why they end up tucked into so many beds.

Feeding the good bugs

Not every insect is a problem. Flowers and flowering herbs feed the predators that eat your pests, from ladybugs to lacewings to tiny parasitic wasps. Let a few dill or cilantro plants flower and they become a magnet for those helpers, which then patrol the squash and tomatoes nearby. Nasturtium plays a different trick: aphids pile onto it and leave your beans and greens alone, so it works as a living trap.

Sharing food and space

Beans and peas pull nitrogen from the air and leave the soil richer for hungry crops like corn and squash that follow them. Pairing a deep-rooted crop like carrots with a shallow one like onions or lettuce lets them draw from different layers of soil instead of competing. And a tall plant can shade a short one or stand in for a trellis, so one bed does the work of two.

Three classic combinations

The Three Sisters: corn, beans, and squash

This is the most famous trio in the garden, and it earns the reputation. Corn gives the climbing beans a living pole. The beans feed nitrogen back to all three. The broad squash leaves shade the ground, hold in moisture, and smother weeds. Plant the corn first, add pole beans once the stalks are knee-high, then tuck squash around the base.

Tomato and basil

The pairing that works on the plate works in the bed too. Basil's strong scent helps cover your tomatoes from a few common pests, and the two have grown side by side for generations. Basil also stays low, so it fills the bare space at the foot of a staked tomato instead of leaving it empty.

Carrots and onions

An old favorite for good reason. The onion smell helps throw off the carrot rust fly, and the carrot smell helps confuse the onion fly, so each one looks after the other. They root at different depths too, which means they share a row without crowding. Slip in some lettuce or radish to use the gaps while the roots size up.

Plants to keep apart

Not every neighbor helps. Keep onions and garlic away from beans and peas, since the alliums can stunt young legumes. Give fennel its own corner, because it sits poorly next to almost everything. Keep tomatoes away from cabbage-family crops and from corn, which share the same pests and diseases, and do not crowd potatoes in beside squash or tomatoes. When two heavy feeders both want the same spot, give them their own space instead of forcing it.

Starting your own plan

Begin with the chart, but plant what you will actually cook and eat. Run marigolds and nasturtium along the edges as all-purpose helpers, keep a patch of beans or peas to feed the soil, and let a few herbs flower for the pollinators. The real skill comes from watching. Notice what thrives next to what in your garden, then do more of it next year.

Related guides

• Types of Beans: A Complete Guide to Bush, Pole, Snap & Shell Varieties
• Types of Peppers: The Complete Chart from Sweet Bells to Superhots