Ethan BrooksBy Ethan Brooks

Updated November 2026

A gardening companion planting chart shows which vegetables, herbs and flowers grow well side by side and which ones compete or attract the same pests. Using one lets you plan a bed so that plants support each other, use space efficiently and produce a stronger harvest. This guide explains how to read a chart, build your own, and avoid the mistakes that undo good planning.

How to Read a Companion Planting Chart

Most charts list a crop down the left side and its partners across the top, with a symbol or color for each pairing. A “good” pairing usually means the two plants share a bed without hurting each other, or one deters pests that bother the other. A “bad” pairing usually means they compete for the same nutrients or share a disease. Charts are useful starting points, but they are not rules. Results depend on soil, climate, and how much space you give each plant.

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

Before you trust any chart, check three things: whether it cites its sources, whether it covers the crops you actually grow, and whether it lists spacing alongside pairings. A pairing that works in a 4-foot bed may fail in a crowded row.

Build Your Own Chart for Your Garden

A generic chart is a good start, but a version built around your own crops is far more useful. Start with the vegetables you plant every year, then add the herbs and flowers you want to try. Use one row per crop and record the best partners, the plants to keep apart, and the spacing you actually use.

  1. List your main crops, such as tomatoes, peppers, beans, squash, lettuce and carrots.
  2. Look up each crop in two or three reliable extension or university sources and note the pairings they agree on.
  3. Record minimum spacing in inches for each crop, since spacing determines whether a pairing is possible at all.
  4. Mark known conflicts, such as plants that share soilborne diseases or compete heavily for water.
  5. Update the chart after each season with notes on what worked in your specific beds.

Apply Chart Pairings to Your Beds

Once you have a chart, the next step is laying out beds. Group plants by their height and sun needs first. Tall crops like corn or pole beans should go on the north side of a bed so they do not shade shorter plants. Put low, shade-tolerant crops such as lettuce or spinach where they will get some afternoon shade in summer.

Then check each planned pairing against your chart. A common and reliable example is basil planted near tomatoes, though the benefit is mostly about pest attraction and garden layout rather than proven yield gains. If you use raised beds, you can also plan by square, which makes it easy to fit multiple companions into one frame. For square-based layouts, see Square Foot Gardening Companion Planting: A Step-by-Step Guide.

Plan Spacing and Rotation Together

Companion planting only works if plants have room to grow. Overcrowding causes the same problems a bad pairing does: poor airflow, more disease, and weaker yields. Use the spacing listed for each crop, and leave walkways so you can harvest and inspect without stepping into the bed.

Rotation matters too. Even a good pairing will struggle if the same family of plants returns to the same spot every year. Move brassicas, nightshades and legumes to a different bed each season. For a closer look at one crop, see Tomato Companion Planting Chart: Best Partners, Spacing and Pitfalls and Pepper Companion Planting Chart: Which Plants to Pair (and Avoid).

Common Mistakes

  • Treating a chart as a guarantee. Pairings reduce risk; they do not replace good soil, watering and monitoring.
  • Ignoring spacing, which turns a helpful neighbor into a competitor.
  • Planting herbs like rosemary or oregano close to crops that need more moisture, since they prefer drier conditions.
  • Forgetting that some plants, like squash or mint, spread aggressively and need their own space.
  • Failing to record results, so the same mistakes repeat every spring.

A simple gardening notebook or a printed chart pinned inside a shed door makes it easy to check pairings while you plant. A soil thermometer helps you time sowing for the crops on your chart, since many companions go in at similar temperatures. A layout grid or string grid for raised beds makes spacing easy to measure: View on Amazon.

FAQ

Are companion planting charts scientifically proven?

Some pairings have research behind them, while others rest on long-standing gardening practice with mixed evidence. Treat charts as a practical guide and test them in your own beds.

Should I follow every pairing on a chart?

No. Choose the pairings that fit your space, sunlight and the crops you most want to grow. Skip the rest rather than forcing plants into a crowded bed.

How often should I update my chart?

Review it at the end of each growing season. Note which pairings produced healthy plants and which ones struggled, then adjust for next year.

Conclusion

A gardening companion planting chart is most useful when you build it around your own crops, spacing and climate. Pair plants with clear reasons, space them properly, and rotate beds each season. Keep notes, and your chart will get more accurate every year.

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Ethan Brooks

About Ethan Brooks

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