Graham FisherBy Graham Fisher

Updated November 2026

A companion planting guide for raised beds helps you decide which vegetables to grow side by side, how far apart to set them, and which combinations to avoid. Done well, companion planting can help you use limited bed space more efficiently, reduce some pest pressure, and keep your harvest steady from spring through fall. This guide walks through the basic steps for planning a bed that works as a team.

Start With Your Bed Size and Sun Exposure

Before you choose any pairings, measure your bed and note how many hours of direct sun it gets. Most vegetables need six to eight hours of sun, so a bed in partial shade should be reserved for leafy greens, peas and herbs like parsley or mint. A standard 4-by-8-foot bed gives you 32 square feet, which is enough room for a mix of tall, medium and low-growing crops if you plan the layout on paper first.

Shopping for one? See our guide: Companion Planting with Pole Beans: 5 Best Picks for 2026.

Pair Crops by Height, Root Depth and Growth Habit

Companion planting works best when plants fill different layers and don’t compete for the same nutrients at the same depth. Put tall crops on the north side of the bed so they don’t shade shorter plants. Pair deep-rooted crops with shallow-rooted ones, such as carrots with lettuce, so they draw from different soil zones. Fast-maturing crops like radishes can fill gaps between slower plants like peppers or brassicas. For a worked example of how this looks in a real bed, see Raised Bed Garden Layout Companion Planting: A Step-by-Step Guide.

Some pairings have a long track record among gardeners. Basil planted near tomatoes is often grown together for flavor and as a companion, and marigolds are widely planted along bed edges to attract beneficial insects. Beans can add nitrogen to the soil, which benefits heavy feeders like corn and squash. For a broader list of pairings, the Vegetable Companion Planting Guide: Pairings, Spacing and Pitfalls (2026) covers more combinations.

Plan Spacing Before You Plant

Crowding is the most common reason companion plantings fail. Each crop has a recommended spacing, and squeezing plants too close increases disease risk because air doesn’t circulate well. Use these general guidelines when laying out your bed:

  1. Check the mature spread of each crop on the seed packet or plant tag.
  2. Use a grid of 12-inch squares for medium plants and 18-inch squares for large ones.
  3. Leave at least 6 inches between a tall plant and a shorter companion so the shorter one still gets light.
  4. Mark planting spots with string or a template before you dig.

Build a Simple Bed Map and Rotate Each Season

Draw your bed on graph paper or a notes app and record what goes where. Keep the map with your garden journal so you can rotate crops the next year. Avoid planting the same family in the same spot two seasons in a row, since soil-borne diseases can build up. Rotation matters as much as companionship, and it keeps your pairings from becoming a disease highway over time.

Common Mistakes

  • Assuming every “good neighbor” pairing works in every climate. Heat, humidity and soil type all change results.
  • Planting alliums such as onions and garlic next to peas or beans, which can slow their growth.
  • Ignoring the mature size of a plant and ending up with a shaded, crowded bed by midsummer.
  • Using a single pairing as a pest solution. Companion plants can support pest control but rarely replace monitoring and hand-picking.
  • Forgetting to water companions separately when their needs differ, such as lettuce versus melons.

A soil thermometer helps you time sowing for warm-season crops like basil and squash that won’t perform in cold ground. View on Amazon

A bed planning notebook or grid-marked garden journal makes it easier to track rotations and spacing from year to year. View on Amazon

A soil pH test kit lets you confirm your raised bed mix suits the crops you plan to pair. View on Amazon

FAQ

Do companion plants really reduce pests?

Some do, mainly by attracting beneficial insects or masking the scent of target crops. Results vary, so use companion planting alongside regular inspection and other pest controls.

How far apart should companion plants be in a raised bed?

Follow the mature spacing on each plant’s label, usually 12 to 18 inches for most vegetables. Give tall plants enough room that they won’t shade shorter neighbors.

Can I use companion planting in a small raised bed?

Yes. Focus on two or three well-matched pairs rather than trying to fit many crops, and use vertical supports for vining plants to save space.

Conclusion

A good companion planting plan starts with your bed’s size, sun and crop heights, followed by careful spacing and a simple map. Pair crops that complement each other, avoid known conflicts, and rotate families each season. With those basics in place, your raised bed will be easier to manage and more productive.

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Graham Fisher

About Graham Fisher

Graham Fisher is part of our editorial team and reviews and edits our vegetable & edible gardening guides, checking product details against manufacturer specifications and owner feedback.