The culmination of the growing season for gardeners is the tomato harvest. However, getting from seed to fruit can be challenging. Aphids, whiteflies and thrips damage the leaves and deform the fruit by sucking the sap from plants. Worms and maggots feed on the leaves or bore into the fruits and buds. Beetles and caterpillars chew holes in the leaves, causing plants to become stunted. Interplanting herbs and vegetables with tomatoes can inhibit these pests.
The strong odor emitted by plants of the allium family, such as chives, garlic, leeks, onions and shallots, will repel a number of pests. Above ground, these plants protect tomatoes from aphids and red spiders, while below ground they repel nematodes. (Ref 4)
Basil performs several functions relating to tomatoes. When paired in the kitchen, these two plants are the foundation for sensational salads and delicious sauces. In the garden, the workhorse basil attracts pollinating bees while deterring aphids, spider mites, thrips, and whiteflies and repelling tomato hornworms. (Ref 4 & Res 1)
Another garden workhorse, borage also benefits tomatoes in several ways. This edible herb not only improves the growth and flavor of tomatoes, but it also repels tomato hornworms and attracts bees and beneficial predatory wasps.
A member of the apiaceae family, coriander also repels aphids and attracts bees to the garden. To eliminate spider mites, brew a coriander tea by crushing 1 tsp. of dried leaves or seeds and steeping it in a cup of boiling water. After the tea cools, spray it on the affected plant.
French Marigold (T. Patula)
The strong scent of French marigolds makes them welcome throughout the garden. These plants, much like members of the allium family, exude their strong smell both above and below the surface. When teamed up with tomatoes, French marigolds will repel whiteflies and nematodes.
In addition to its uses as a tasty salad ingredient and as a garnish in iced tea, mint adds to the health of tomatoes. As an insect repellent, mint deters aphids and other destructive insects. This extremely invasive perennial is particularly attractive to predatory wasps and earthworms.
The pretty, edible blossoms of the nasturtium add color and interest to the garden. Additionally, this versatile flower serves as a deterrent to aphids, beetles, and whiteflies while protecting plants from fungal diseases.