By Ethan BrooksUpdated November 2026
A companion planting square foot gardening chart tells you which vegetables and herbs to grow side by side in each 1-foot square, and how many plants fit in that square. Once you understand the spacing numbers and the pairing logic, you can lay out a bed in an afternoon and avoid the crowding and pest problems that come from guessing. This guide shows you how to read a chart, build your own grid and check it against the plants you actually want to grow.
Understand How the Square Foot Grid Works
Square foot gardening divides a bed into 1-foot squares, usually with string, wood strips or a grid of lath. A standard 4-by-8-foot bed holds 32 squares. Each square is planted with a fixed number of plants based on their mature size, such as 1 tomato, 4 bush beans, 9 carrots or 16 radishes. That spacing number is what makes a chart useful: the companion pairings only work if each square holds the right count.
Shopping for one? See our guide: 6 Best Garden Layout Free Printable Printable Companion Planting Charts (2026): Our Picks.
Most charts list three things for each crop: the number of plants per square, the best neighbors and the plants to keep away. Read the spacing first, then check the neighbor column, so you know whether a pairing will fit your grid.
Build Your Own Companion Planting Chart
A printed chart is a starting point. For your own garden, build a short working version with only the crops you plan to grow. Use these steps:
- List every crop you intend to plant and write its plants-per-square number beside it.
- For each crop, note two or three good companions and any plants it should not share a square or neighboring square with.
- Sketch your bed on graph paper at 1 square per foot, marking the tall crops on the north side so they don’t shade shorter plants.
- Assign each square a crop, keeping conflicting plants at least one square apart.
- Check that no square holds more plants than its spacing number allows.
Use Pairings and Spacing Together
Pairings matter, but spacing matters more. A square of carrots next to a square of onions works well because the two crops do not compete much for the same nutrients and the onions may help deter carrot flies. Tomatoes can share space with basil or parsley, while peppers do well with carrots and basil. Keep in mind that any pairing still needs the right number of plants per square, or you will end up with crowding and poor airflow that invites disease.
| Crop | Plants per square | Good neighbors | Keep apart from |
|---|---|---|---|
| Tomato | 1 | Basil, parsley, carrots | Potatoes, fennel |
| Carrot | 16 | Onion, lettuce, peas | Dill |
| Bush bean | 9 | Carrot, cucumber, radish | Onion, garlic |
| Pepper | 1 | Basil, carrot | Fennel, beans |
For more pairing detail by crop, see Veggie Companion Planting Chart: Pairings, Spacing and Pitfalls (2026) and Pepper Companion Planting Chart: Which Plants to Pair (and Avoid).
Plan for Succession and Rotation
Once a square’s crop is harvested, you can replant it. Radishes finish in about 4 weeks, so a square can take a second crop of lettuce or bush beans. Keep plant families in roughly the same area from year to year to limit soil-borne disease, and rotate where possible. For a fuller layout approach, Companion Planting in a Square Foot Garden: A Step-by-Step Guide walks through the full seasonal plan.
Common Mistakes
- Planting more than the spacing number per square, which crowds roots and leaves.
- Placing tall plants on the north side of the bed where they can shade everything else.
- Trusting a chart without checking the mature size of the variety you bought.
- Forgetting that companion benefits are mostly about pest and nutrient balance, not guaranteed results.
- Skipping the labels, which makes it hard to track what went where next season.
Recommended gear
A square foot grid is easiest to set up with a few basic tools. A grid of garden lath or a string frame makes squares easy to mark and keeps them even. A soil thermometer helps you time sowings for cool-season crops in the square. A simple plant label set keeps each square’s crop and planting date on record.
- Square foot garden grid kit: marks each 1-foot square so spacing stays accurate. View on Amazon
- Soil thermometer: helps you check soil temperature before sowing. View on Amazon
- Plant labels: keep track of crops and sowing dates in each square. View on Amazon
FAQ
How many plants go in each square foot?
It depends on the crop’s mature size. A tomato takes the whole square, while carrots and radishes fit 16 per square. Check the spacing column on your chart before you sow.
Do I need to follow every companion pairing?
No. Pairings are helpful guidelines, not rules. Start with the pairings that fit your space and your pest problems, and adjust next season based on what you observe.
Can I use a companion planting chart for containers?
Yes, though container spacing is tighter and watering needs differ. Use Container Companion Planting Chart: 8 Pairings That Work (2026) as a reference for smaller spaces.
Conclusion
A companion planting square foot gardening chart gives you two things at once: the right number of plants for each square and the pairings that help them grow well together. Build a simple chart for your own crops, sketch your bed on a 1-foot grid and check spacing before you plant. Keep notes each season so your layout improves over time.
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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.
