Companion Planting Calculator
Create harmonious plant relationships for a healthier, more productive garden
Professional Advice Recommended While this calculator provides helpful estimates based on standard parameters, individual circumstances may vary. For critical applications or specialized projects, we strongly recommend consulting with a qualified professional in the relevant field (gardening, construction, healthcare, etc.) before making final decisions. The results should be used as a general guideline only and do not replace expert advice.
Note: Companion planting suggestions are based on traditional gardening knowledge. Results may vary based on your specific growing conditions.
Gardener's Tip: Plant basil with tomatoes to improve flavor and repel pests. Marigolds work well with most vegetables as natural pest deterrents.
Primary Plants
Companion Preferences
Companion Planting Plan
Primary Plants:
Recommended Companions:
Plants to Avoid:
Optimal Spacing:
Tomato
Basil, Marigold, Onion
Cabbage, Corn
12-24" between plants
Planting Layout: Alternate tomatoes with basil in rows
Additional Benefits: Basil improves tomato flavor, marigolds deter nematodes
Care Tips:
- Plant marigolds as a border around tomato patch
- Harvest basil regularly to encourage bushiness
Companion Planting Principles
Beneficial Combinations
- Three Sisters: Corn, beans, and squash
- Tomato Friends: Basil, onion, marigold
- Cabbage Family: Dill, mint, rosemary
- Carrot Allies: Chives, leeks, peas
Plants to Keep Apart
- Tomatoes with potatoes or cabbage
- Beans with onions or garlic
- Cucumbers with aromatic herbs
- Strawberries with cabbage family
"Gardeners using companion planting report 20-30% fewer pest problems and increased yields compared to monoculture planting."
Top Companion Plants by Function
Pest Control
Marigolds: Deter nematodes, repel whiteflies. Plant throughout garden.
Nasturtiums: Trap crop for aphids, repel squash bugs. Grow near cucumbers.
Basil: Repels thrips and mosquitoes. Excellent with tomatoes.
Soil Improvement
Beans/Peas: Fix nitrogen in soil. Plant with heavy feeders like corn.
Borage: Accumulates minerals, improves soil structure.
Comfrey: Deep roots bring up nutrients. Use as mulch.
Flavor Enhancers
Basil: Improves tomato flavor and growth.
Chamomile: Enhances flavor of cabbages and onions.
Dill: Improves health of cabbage family plants.
Pro Tip: Rotate companion plants annually to prevent soil-borne diseases and maximize benefits. Keep a garden journal to track what combinations work best in your microclimate.
Frequently Asked Questions
How close should companion plants be?
Ideal spacing varies by plant combination. Generally, plant companions within 1-3 feet of each other. Our calculator provides specific spacing recommendations based on your selected plants and garden size.
Can companion planting eliminate pests completely?
While companion planting significantly reduces pests, it rarely eliminates them entirely. It works best as part of an integrated pest management strategy that includes crop rotation, healthy soil, and physical barriers when needed.
Do companion plants work in containers?
Yes! Container gardens benefit greatly from companion planting. Our calculator adjusts recommendations for pot size when you select "Container Garden." Good container combinations include tomatoes with basil or peppers with marigolds.
How do I know which plants are good companions?
Our database contains scientifically validated and traditionally proven combinations. Generally, plants from different families with complementary growth habits make good companions. We highlight both beneficial pairs and plants to avoid.
Should I change companions each year?
Rotate plant families annually to prevent disease buildup, but successful companion pairs can be repeated. Try alternating between different beneficial combinations in the same space across seasons for maximum soil health.