Companion planting pairs specific crops so one supports the other — through pest deterrence, efficient use of space, or shared nutrient needs — while keeping incompatible pairings apart. The chart below covers the most-searched, most reliable pairings for a home garden, organized by main crop so you can look up exactly what you're planting.
Vegetable Companion Planting Chart
| Main Crop | Good Companions | Avoid Planting Near |
|---|---|---|
| Tomatoes | Basil, marigold, carrots | Brassicas (cabbage, broccoli), fennel |
| Cucumbers | Radishes, marigold, dill | Aromatic herbs like sage |
| Lettuce | Carrots, radishes, marigold | Broccoli (heavy shade competition) |
| Carrots | Onions, lettuce, rosemary | Dill (can cross-affect flavor and attract shared pests) |
| Beans | Corn, marigold, cucumbers | Onions, garlic |
| Peppers | Basil, marigold, carrots | Fennel, kohlrabi |
Why These Pairings Actually Work
Pest deterrence is the most common mechanism: marigolds release compounds that can deter certain nematodes and insects, which is why they appear as a good companion across nearly every crop in the chart above. Scent masking is another factor — onions planted near carrots can help mask the scent that attracts carrot fly. Nutrient sharing explains the beans-and-corn pairing specifically: beans fix nitrogen in the soil that heavy-feeding corn benefits from directly.
Pro tip: Marigold is the single most versatile companion plant in this entire chart — it pairs well with nearly every vegetable listed and is one of the few plants with almost no documented incompatible pairings, making it a safe default addition to nearly any vegetable bed.
Why the "Avoid" Pairings Actually Matter
| Pairing to Avoid | Reason |
|---|---|
| Tomatoes + Brassicas | Compete heavily for the same soil nutrients |
| Beans + Onions/Garlic | Alliums can inhibit bean growth and nitrogen fixation |
| Carrots + Dill | Can cross-attract the same pests and affect each other's growth |
| Cucumbers + Aromatic herbs (sage) | Strong aromatics can slow cucumber growth nearby |
Building Your Companion Planting Bed
- Choose your main crop first — tomatoes, cucumbers, or another focal vegetable
- Add one companion from the "good companions" column for pest support
- Cross-check anything else you're planning to add against the "avoid" column before finalizing your layout
Shop the exact varieties featured in this chart: tomato seeds, marigold seeds, cucumber seeds, and lettuce seeds.
Frequently Asked Questions
What is the best companion plant for tomatoes?
Basil and marigold are the two most commonly recommended companions for tomatoes, both for potential pest-deterrent benefits and efficient use of garden space.
Why shouldn't you plant tomatoes near cabbage?
Tomatoes and brassicas like cabbage compete heavily for the same soil nutrients when planted close together, which can reduce yield for both crops.
Does marigold really repel pests?
Marigolds release compounds in the soil and air that can deter certain nematodes and some insects, which is why they're widely recommended as a companion plant across many different vegetables.
Explore our full vegetable seed collection to build your own companion-planted garden.
