Enhance Your Garden Tomatoes With A Fresh-Smelling, Flowering Companion

Understanding the benefits one species provides to another simply because they're planted together is the foundation of companion planting. Some pairings, like carrots and onions, are mutually beneficial. The smell of onions keeps carrot-loving pests away while carrot fronds suppress weeds around the onions. In others, one plant does all the work. For example, cucumbers can benefit from sunflowers' trellis-like height, their shade, and their attractiveness to pollinators. Companion plants for tomatoes can be early indicators of disease, like basil, or they can ward off nematodes, as marigolds sometimes do. But one fragrant, colorful perennial, lavender (Lavandula spp.), disorients common tomato pests with its strong aroma.

Lavender may bewilder pests like moths, mosquitos, and snails by masking the scent of the tomato plants. For pests that rely on sight, lavender can also make it difficult to find their desired target. The bushy perennial not only benefits tomatoes by confusing pests; it also attracts pollinators like bees, a benefit that places lavender on the list of the best plants for a pollinator garden. While tomatoes are self-pollinating, meaning the flowers have both male and female reproductive parts, bees and butterflies boost the chance of successful fruits by increasing the amount of pollen released and transferred. 

Hardy in USDA zones 5 through 9, lavender can grow up to 3 feet tall and spread 2 feet wide, with grey-green two-inch-long leaves. The bushy plant prefers full or partial sun and neutral to alkaline soil. The small flowers grow on spikes, blooming in the summer with expected shades ranging from white to lilac to purple, but there are even yellow cultivars. Lavender is neither aggressive nor invasive, and it's resistant to deer, drought, and rabbits. Because lavender is a sub-shrub, it should not be severely pruned, though harvesting the flowers isn't harmful. If you experience a cold winter, protect the plants with extra mulch use a mulch substitute and cover them during long cold snaps. 

Since lavender is a perennial and tomatoes are annuals, it might seem counterintuitive that they can both thrive when grown together. While lavender's ideal soil is rocky and dry, it will tolerate the rich soil that tomatoes thrive in. The sweet spot for soil pH that's ideal for lavender and tomatoes is a neutral 7. Measure the pH of your soil with a home test kit or contact your local extension office. Both plants benefit from moist, well-drained soil. If you've mulched the lavender, it shouldn't need fertilizer, but beware that it may have more foliage than beneficial blooms if it gets too many nutrients. Tomatoes, on the other hand, should be fertilized when they start to set fruit, but usually don't need additional fertilization. Apply the fertilizer to the tomato plants by hand, or use fertilizer spikes set close to the plant. Try not to expose the lavender to the fertilizer, but even if you do expose it to the one-time application, the effects shouldn't be permanent.