Herbs used in cooking enhance the flavors of your foods. Herbs used in your garden enhance the health of your garden. Herbs deter pests and attract beneficial insects, and some may add flavor to the vegetables as they mature on the plant. Some herbs exude scents that attract or repel insects without disrupting the natural food chain within the ecosystem of your garden.
The earthy aroma of a rosemary plant repels cabbage fly, carrot fly and bean beetles. Their flowers attract bees to your garden, and the bees pollinate your flowering plants. Rosemary also provides a habitat for ladybugs to lay their eggs. Ladybugs in your garden greatly reduce any aphid infestation on your plants.
Carrot fly, beetles and slugs dislike the scent of sage. Plant this woody herb near your carrot patch and squash plants, but not near your cucumbers.
Protect your cucumbers with the tall and willowy dill plant. Dill attracts such beneficial bugs as the parasitic wasp and deters the cucumber beetle. Like rosemary, dill also attracts bees needed for pollination. Mature dill plants may negatively affect your tomato plants, which are sensitive to certain scents such as tobacco and dill. Keep dill away from your tomatoes, and don't smoke in your garden.
Thyme is a prolific herb but may be harvested frequently. If you have raised beds, plant thyme as a ground cover between your beds. Walking on thyme releases its delicate scent. Thyme deters white fly, cabbage fly and, when flowering, attracts bees and wasps to your garden.
The lovely scented lavender attracts a host of beneficial bugs, including bees for pollinating and the parasitic wasp for eating pests. Create a border of lavender for your garden to deter moths.
Plant tansy near your raspberries and grapes to prevent borers and near your squash to discourage squash bugs. Tansy also concentrates potassium, a necessary nutrient for most plants, in the soil. Cut back tansy in the fall and add the cuttings to your compost to increase its nutrient value.
Yarrow is a tall, flowering plant that attracts ladybugs to your garden. The nectar of the flower also attracts hoverflies and wasps, both predatory insects that aid in controlling pests such as aphids and white fly. Yarrow is also thought to concentrate the oils within nearby plants, thereby increasing their ability to process nutrients and produce more flavorful fruits.