Plants helping plants
Companion Planting
Pair flowers with food: pollinators in, pests out, more flavour.
Great combos
- Tomato + Basil — flavour and shared care.
- Chilli + Marigold (tagetes) — pulls pollinators and confuses pests.
- Kale + Chives — where aphids lurk.
- Carrot + Spring onion — muddle carrot fly with onion scent.
- Strawberry + Thyme — bee traffic and dry-loving partners.
- French beans + Nasturtiums — lure aphids away and give edible flowers.
Things to avoid
- Overcrowding — blocks airflow and invites mildew.
- Mismatched thirst — rosemary with basil rarely ends well.
- Deep roots with shallow in tiny pots — they compete hard.
- Tomatoes with potatoes in containers — disease crossover and space clash.
Pollinator boost
Add edible flowers — nasturtiums, calendula, violas. Let a few herbs bloom (basil, chives, oregano, thyme). Keep sprays away: try hand removal, water blasts and sticky cards first.
Container pairings by pot size
| Pot | Plant together | Why it works | Skip |
|---|---|---|---|
| Window box 5–7 L | Parsley + Chives + Viola | Shallow, frequent snips; bee-friendly faces. | Tomato — too thirsty/top heavy. |
| 10–12 L | Chilli + Basil OR Salad + Radish | Warmth lovers that share watering rhythm. | Mint — spreads aggressively. |
| 20 L | Tomato (bush) + Basil + Marigold | Classic trio; flowers bring pollinators. | Potato — blight risk. |
| 40 L tub | Courgette + Nasturtiums (edge) | Nasturtiums trail, draw aphids, and you can eat the flowers. | A second courgette. |
Mini 'guilds' by goal
- Pest deterrence: Brassicas + chives/garlic chives; Beans + nasturtiums; Lettuce + dill (hoverflies).
- Flavour & yield: Tomato + basil; Strawberry + thyme; Cucumber + dill.
- Shade & living mulch: Chilli + oregano (drapes and cools); Courgette + low nasturtiums.
- Nutrient helpers: Peas/beans followed by leafy greens in the same tub after top-up.
Rotation & hygiene in pots
Don't grow tomatoes in the same tub two years running — follow with salads or flowers and refresh a third of the mix. Lift tired roots after harvest, top up with fresh compost and a small handful of slow-release feed. Wipe stakes and clips before re-using, especially after blight or mildew.
Rule of thumb
If two plants enjoy the same sun and watering routine, they're good candidates to share a pot. Healthy space beats the 'right' combo squashed in.