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Leek and Tomato Companion Planting

By Theresa Leschmann ; Updated September 21, 2017
Harvested leeks
leek image by AGITA LEIMANE from Fotolia.com

Companion planting is a technique used to get the most out of a garden, primarily a vegetable garden. It is employed when only small spaces are available or when boosting production of fruits and vegetables is desired. Understanding what companion gardening is and how to employ it where it pertains to tomatoes and leeks can increase the yield from your garden.

What is Companion Planting?

Companion planting is the grouping of plants that, when planted near each other, produce better yields, better tasting fruits or vegetables or simply grow better. Some plants have this effect on specific plants or whole families. Planning your garden with companion plants in mind will help you get the most out of your garden.

Companions for Leeks

Leeks are in the onion family of plants and prefer beds planted in the full sun though partial shade is tolerated. They have moderate soil nutrient and water requirements. Plants with similar soil, sunlight and watering requirements make natural companions. Among them are bush beans, beets, carrots, celery, garlic, onions, parsley and tomatoes. Leeks also like to be near apple trees.

Companions for Tomatoes

Tomatoes on the vine
tomatoes image by Horticulture from Fotolia.com

Tomatoes are a family of their own and there are hundreds of varieties. Tomatoes like warm temperatures and full sun. They require lots of watering during the growing period but less during the harvest. They have only low soil nutrient requirements, making them compatible with many plants, including some flowers. Companion plants to use with tomatoes are asparagus, basil, bush beans, carrots, celery, anything in the cabbage family, cucumbers, garlic, mint, marigolds parsley, peppers and anything in the onion family.

Plants to Avoid for Leeks

Leeks dislike any beans that are not bush types and all peas. Peas don’t do well when any member of the onion family is planted nearby. Pole beans also have a negative impact on leeks. It is best to keep these plants in separate beds altogether. Avoid planting leeks in beds where shallots, onions, chives or garlic were previously planted.

Plants to Avoid for Tomatoes

Because of the tomato’s modest needs, very few plants are bad companions. Those you will want to avoid include pole beans, dill, fennel and potatoes. Pole beans require light watering, which would hurt tomatoes. Dill requires heavy watering all season making it an unsuitable companion. Fennel is very particular and only tolerates plants in the mint family. Potatoes are in the tomato family and don’t do well side by side. Do not plant in beds where potatoes, peppers or eggplant previously grew.