Companion plants
Companion planting is where you plant multiple different plants together as they provide benefits to one or eachother. This can range from nutrients, to pest resisting, attracting pollinaters and much more.
Companion planting sadly has a fairly limited amount of scientifical information. This means that there can be a lot of hit-and-miss. Regardless of that, whilst it may not always reap benefits, it's not bad to try.
The effectiveness can also differ between species.
Apple
Nasturtium - repels codling moth
Apricot
Basil - repels insects
Asparagus
Basil - improves flavour
Calendula - deters asparagus beetles
Parsley - improves flavour
Petunia - deters asparagus beetles
Tomatoes - deters asparagus beetles
Basil
Purslane - provides soil shade
Bean
Corn - provides support
Lovage - insect repeller
Rosemary - Insect repeller
Sunflower - provides support and shade
Broccoli
Nasturtium - attracts caterpillars away (plant nearby)
Cabbage
Dill - attracts beneficial insects
Garlic - repels cabbage white butterfly
Nasturtium - attracts caterpillars away (plant nearby), deters beetles and aphids
Sage - helps repel cabbage moths
Carrot
Chives - improves growth and flavour, deters aphids, mites and flies
Leeks - repel carrot rust fly
Rosemary - repels carrot fly
Sage - repels carrot fly
Corn
Beans - provides nitrogen
Dill - deters aphids and mites
Spinach - provides soil shade
Sunflower - structure and windbreak
Courgette / Zucchini
Buckwheat - attracts pest predators
Nasturium - deters aphids and whiteflies
Cucumber
Dill - deters aphids and mites
Nasturtium - improves growth and flavour, deters aphids and beetles
Oregano - deters pest
Radish - repel cucumber beetle and flea beetle
Sunflower - provides support and shade
Kale
Nasturtium - attracts caterpillars away (plant nearby)
Lettuce
Basil - improve flavour and growth
Chives - deters aphids and pests
Garlic - deters aphids and pests
Onion - deters aphids and pests
Poached egg plant (flower) - attracts hoverflies which control aphids
Zinnia - attracts pollinators, provides shade
Onion
Marigold - reduces egg laying of onion maggot fly
Pea
Chives - deters aphids
Alyssum - attracts pollinaters
Pepper
Basil - improves growth and flavour, repels insects
Marjoram - repels insects
Oregano - repels insects
Potato
Bean - improves size of tuber
Catmint - repels potato beetle (but can bring cats)
Coriander - protects against aphids, spider mites and potato beetle
Horseradis - repels potato beetles
Marigold - suppresses weeds
Pumpkin
Buckwheat - attracts pest predators
Nasturtium - deters pumpkin and squash beetles
Oregano - deters beetles and root nematodes
Radish
Chervil - imrpoves growth and flavour
Peas - provides nitrogen
Spinach
Beans - provides shade
Coriander - repels insects
Oregano - repels insects
Peas - provides shade
Rosemary - repels insects
Strawberry
Borage - enhances flavour and vigour, increases yield
Tomato
Asparagus - repels nematodes
Basil - can repel and disorient certain pests, can attract bees, improves growth and flavour of tomatoes
Borage - attracts pollinaters, repels hornworms
Calendula - deters pests
Lemon balm - improves flavour and growth, repels insects
Marigold - deters nematodes
Parsley - attracts beneficial insects, improves flavour
Thyme - reduces egg laying by armyworms
Honourable mentions
Mint - deters aphids, ants and flea beetles
not in the list because if can be a very aggresive grower. Keep seperate in a pot nearby
Tansy - deters ants, beetles, bugs
not in the list because it can be very poisonous
Companion planting sadly has a fairly limited amount of scientifical information. This means that there can be a lot of hit-and-miss. Regardless of that, whilst it may not always reap benefits, it's not bad to try.
The effectiveness can also differ between species.
Apple
Nasturtium - repels codling moth
Apricot
Basil - repels insects
Asparagus
Basil - improves flavour
Calendula - deters asparagus beetles
Parsley - improves flavour
Petunia - deters asparagus beetles
Tomatoes - deters asparagus beetles
Basil
Purslane - provides soil shade
Bean
Corn - provides support
Lovage - insect repeller
Rosemary - Insect repeller
Sunflower - provides support and shade
Broccoli
Nasturtium - attracts caterpillars away (plant nearby)
Cabbage
Dill - attracts beneficial insects
Garlic - repels cabbage white butterfly
Nasturtium - attracts caterpillars away (plant nearby), deters beetles and aphids
Sage - helps repel cabbage moths
Carrot
Chives - improves growth and flavour, deters aphids, mites and flies
Leeks - repel carrot rust fly
Rosemary - repels carrot fly
Sage - repels carrot fly
Corn
Beans - provides nitrogen
Dill - deters aphids and mites
Spinach - provides soil shade
Sunflower - structure and windbreak
Courgette / Zucchini
Buckwheat - attracts pest predators
Nasturium - deters aphids and whiteflies
Cucumber
Dill - deters aphids and mites
Nasturtium - improves growth and flavour, deters aphids and beetles
Oregano - deters pest
Radish - repel cucumber beetle and flea beetle
Sunflower - provides support and shade
Kale
Nasturtium - attracts caterpillars away (plant nearby)
Lettuce
Basil - improve flavour and growth
Chives - deters aphids and pests
Garlic - deters aphids and pests
Onion - deters aphids and pests
Poached egg plant (flower) - attracts hoverflies which control aphids
Zinnia - attracts pollinators, provides shade
Onion
Marigold - reduces egg laying of onion maggot fly
Pea
Chives - deters aphids
Alyssum - attracts pollinaters
Pepper
Basil - improves growth and flavour, repels insects
Marjoram - repels insects
Oregano - repels insects
Potato
Bean - improves size of tuber
Catmint - repels potato beetle (but can bring cats)
Coriander - protects against aphids, spider mites and potato beetle
Horseradis - repels potato beetles
Marigold - suppresses weeds
Pumpkin
Buckwheat - attracts pest predators
Nasturtium - deters pumpkin and squash beetles
Oregano - deters beetles and root nematodes
Radish
Chervil - imrpoves growth and flavour
Peas - provides nitrogen
Spinach
Beans - provides shade
Coriander - repels insects
Oregano - repels insects
Peas - provides shade
Rosemary - repels insects
Strawberry
Borage - enhances flavour and vigour, increases yield
Tomato
Asparagus - repels nematodes
Basil - can repel and disorient certain pests, can attract bees, improves growth and flavour of tomatoes
Borage - attracts pollinaters, repels hornworms
Calendula - deters pests
Lemon balm - improves flavour and growth, repels insects
Marigold - deters nematodes
Parsley - attracts beneficial insects, improves flavour
Thyme - reduces egg laying by armyworms
Honourable mentions
Mint - deters aphids, ants and flea beetles
not in the list because if can be a very aggresive grower. Keep seperate in a pot nearby
Tansy - deters ants, beetles, bugs
not in the list because it can be very poisonous