Graham FisherBy Graham Fisher

Updated November 2026

A companion planting raised bed layout puts compatible vegetables, herbs and flowers close together so they support each other, while keeping incompatible crops apart. Done well, the layout improves pest control, makes better use of sun and space, and keeps your harvest steady from spring into fall. This guide walks through planning the bed, placing plants by height and need, and avoiding the pairings that cause trouble.

Start With the Bed Size and Sun Exposure

Before choosing any plant partners, measure the bed and note where the sun falls across the day. Most fruiting vegetables need six to eight hours of direct sun, so a bed that gets only four hours is better suited to leafy greens, herbs and root crops. A standard 4×8-foot bed gives you 32 square feet, which is enough room for a mix of tall, medium and low plants if you plan the grid carefully.

Shopping for one? See our guide: 6 Best Garden Layout Free Printable Printable Companion Planting Charts (2026): Our Picks.

Orient the long side north to south when possible. That way, tall plants on the north edge will not shade the rest of the bed. For another angle, check out Plan for a Companion Planting Garden Design: 7 Steps to Layout Beds.

Place Plants by Height and Growth Habit

Once the sun pattern is clear, assign each zone a height. Put the tallest crops, such as pole beans on a trellis, indeterminate tomatoes or sweet corn, along the north edge. Medium plants like peppers, bush beans and kale go in the middle. Low crops such as lettuce, radishes, carrots and bush basil fill the south edge.

Spacing matters as much as position. Use these common guidelines:

  • Tomatoes: 18 to 24 inches apart
  • Peppers: 12 to 18 inches apart
  • Bush beans: 4 to 6 inches apart
  • Lettuce and spinach: 6 inches apart
  • Carrots: 2 to 3 inches apart after thinning

Crowding leads to disease and weak growth, so err on the side of more space when in doubt.

Pair Compatible Plants in Blocks

Companion planting works best when plants are grouped in small blocks rather than scattered one per square. A block of three basil plants around a tomato, for example, is easier to manage and gives a stronger aroma effect than a single basil stalk. Some well-known pairings to build on include:

  • Tomatoes with basil, carrots and marigolds
  • Beans with carrots, cucumbers and potatoes
  • Squash with nasturtiums and radishes
  • Lettuce with chives and strawberries

For a full pairing walkthrough, see Companion Planting for Raised Garden Beds: A Step-by-Step Guide, which covers each combination in detail. If you are working in a smaller footprint, Small Companion Planting Garden Layout: 6 Steps for Better Yields shows how to fit these blocks into tighter spaces.

Keep Problem Pairs Apart

Some plants inhibit each other’s growth or share pests and diseases, so they should sit at least one bed section apart. Keep alliums such as onions, garlic and chives away from peas and beans. Fennel is generally best grown in its own corner, since it can stunt many vegetables nearby. Potatoes and tomatoes share blight risks, so they belong in different beds or on opposite ends of the same bed. A similar conflict shows up with zucchini and onion, which is covered in Zucchini and Onion Companion Planting: Steps, Spacing and Pitfalls.

Common Mistakes

  • Planting tall crops on the south side, where they shade everything else.
  • Filling every square with a different plant, which makes watering and pest checks harder.
  • Ignoring spacing for tomatoes and squash because the seedlings look small.
  • Planting fennel or potatoes next to crops they are known to disrupt.
  • Forgetting to rotate the layout each season, which lets soil pests and diseases build up.

FAQ

Can I reuse the same companion planting layout every year?

You can keep the general pairings, but rotate crop families to different spots each year. Rotation reduces soil-borne disease and pest buildup.

How many plants should I group together?

Blocks of three to five plants of the same crop, or one main crop plus two or three companions, are easy to manage and work well in most beds.

Do I need a trellis for a companion layout?

A trellis is helpful when you grow pole beans or cucumbers on the north edge, because it lifts vines off the bed and keeps lower plants lit.

Conclusion

A good companion planting raised bed layout starts with sun, height and spacing, then adds compatible pairings and keeps problem crops apart. Sketch your bed on paper before planting, and note what worked at the end of each season. Adjust the plan next year, and your yields will keep improving.

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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.