Fresh crunchy carrots are good by themselves but better when bathed in a butter dill sauce. Juicy tomatoes served with basil leaves and drizzled with olive oil are a summer salad favorite. Crisp green peppers, onions and cucumber, all topped with cilantro and spritzed with lime juice, are a perfect accompaniment for a barbecue. Herbs and vegetables were meant to go together in the garden and on your plate.
Companion planting is based on vegetables and herbs assisting each other grow by adding nutrients to the soil, chasing away insects or supporting each other. For example, borage contains trace elements that help tomatoes and peppers grow faster and boosts strawberry plants yield. Rosemary deters cabbage moths, carrot flies and bean beetles. Pole beans add nitrogen to the soil for corn and uses the corn for support as it grows.
Vegetables and herbs come in cool season and warm season varieties. Plant the same type of vegetable with like herbs. For example, dill and coriander both prefer cool weather. Plant them with cool season crops like peas, lettuces and leafy greens. Basil and oregano are warm season herbs. Plant them with warm season crops like eggplant, squash and bush beans.
Herbs that originated in the Mediterranean don't need rich soil. However, most vegetables prefer soil that has lots of organic matter. When you fertilize the vegetables don't waste the fertilizer on the herbs.
Contain the Herbs
Some herbs, like spearmint, are rampant spreaders. They grow underground by runners. Oregano is a fast spreader and can easily take over a bed. Rosemary grows to 6 feet wide. Plant the herbs where they won't interfere with the rest of the garden. In the case of spearmint, plant it in a terracotta pot with the drainage holes blocked. Then plant the pot in the herb garden with 2 inches of the pot rim above the ground.
Some herbs and vegetables are just made for each other, so plant them next to each other. When you harvest the vegetable, snip some of the herb to go with it. Basil and tomato is a good combination so is dill and cucumbers. Thyme and peas compliment each other. Oregano and garlic are often used in the same dish.