The Self-Seeding Flower You Should Plant With Tomatoes For All Of Its Benefits

Tomatoes are many gardeners' favorite summer crop, but pests can ruin those dreams of homegrown salads and pasta sauces. That's why some growers add a surprising companion plant to their garden beds. More commonly known as an annual bedding flower, sweet alyssum (Lobularia maritima) makes an excellent plant partner for tomatoes — and it can self-seed in your garden year after year.

With flowers that are pink, purple, or white, this annual plant attracts many beneficial insects to the garden. Those tiny but fragrant flowers provide nectar for parasitoid wasps, some of which target aphids, a common pest that'll attack your tomatoes in the garden. Sweet alyssum also appeals to ladybugs and hoverflies, both of which are also powerful allies in fighting aphids. Along with drawing in pest patrollers, this plant also attracts pollinators, which can lead to a more bountiful harvest, so long as the growing conditions are right to support this dainty plant.

With a spreading, mat-like growth habit, these plants reach between 3 and 9 inches tall, making them perfect for use as a ground cover under tomato plants. And since these flowering plants can be grown in full sun to part shade, they'll be fine whether they are on the sunny side of your tomato crop or are somewhat shaded beneath its vines. Sweet alyssum needs well-draining soil and prefers moist conditions, but will tolerate dry conditions occasionally. Often grown as an annual in cooler regions, sweet alyssum is considered a short-lived perennial in USDA Hardiness Zones 9-11.

Whether you decide to grow it among your tomato plants or not, you should count sweet alyssum among the self-seeding flowers to plant for continuous color in your garden year after year. To take advantage of these flowers' tendency to self-seed, let the dead plants overwinter in your garden, removing them only in springtime. Over the winter, the seeds will fall into your soil, allowing a new crop of sweet alyssum flowers to begin growing in the spring. Once you have sweet alyssum established in your garden, be sure to add some additional companion plants to grow next to your tomatoes, such as borage and French marigolds – both of which can also self-seed.