Arugula is a fast-growing, cool-season leafy green known for its distinct, peppery flavor. It matures quickly, often ready for harvest in 20 to 40 days. Arugula performs best in the moderate temperatures of spring and fall, as heat stress causes it to grow bitter or bolt (go to seed). Companion planting uses beneficial relationships between different plant species to improve growth, deter pests, and maximize garden space. Selecting the right neighbors helps create a balanced microclimate that extends the arugula harvest.
Plants That Offer Mutual Benefits to Arugula
Companion plants support arugula by providing shade, improving soil conditions, or repelling common pests. Taller crops can shield arugula from intense afternoon sun, slowing the premature bolting triggered by heat. Bush beans and peas are useful companions because they host nitrogen-fixing bacteria, enriching the soil with nutrients that support leafy growth. The moderate size of bush beans also offers light shade without blocking necessary sunlight.
Aromatic herbs and alliums are beneficial for deterring pests. Chives, onions, and garlic emit strong scents that confuse or repel insect pests, such as the flea beetle, which chews holes in arugula leaves. Dill and cilantro attract beneficial predatory insects like ladybugs and parasitic wasps. These insects naturally control harmful pests such as aphids and caterpillars, protecting the arugula patch.
Low-growing greens, such as lettuce, spinach, and Swiss chard, share similar moisture and temperature needs with arugula. When planted together, they create a dense canopy that covers the soil, maintaining a cooler, more consistent soil temperature. This ground cover effect helps retain moisture, reducing the water stress that causes bitterness in arugula leaves. Root crops like carrots and beets also make good neighbors because their growth is below the soil surface, avoiding competition with arugula’s shallow root system.
Plants to Avoid Planting Near Arugula
Certain plants negatively affect arugula by competing for resources or increasing the risk of pests. Arugula belongs to the Brassicaceae family, which includes cabbage, broccoli, and kale. Planting arugula near these relatives increases the concentration of shared pests, such as flea beetles and cabbage worms, allowing infestations to spread quickly.
Heavy feeders, particularly nightshades like tomatoes, peppers, and eggplants, should be avoided. These long-season vegetables draw substantial nutrients from the soil, depleting resources needed for arugula’s rapid growth. Nightshades also thrive in warmer conditions and a more acidic soil pH than arugula prefers, creating an unfavorable mismatch.
Plants with aggressive root systems or chemical inhibition should be kept at a distance. Sunflowers and corn provide shade but have dense root structures that aggressively compete for water and nutrients. The herb fennel should not be planted near arugula because it releases compounds that inhibit the growth of neighboring plants. Uncontained mint can also quickly overwhelm a planting bed with its vigorous, spreading root system.
Practical Layout and Timing Strategies
The physical arrangement and timing of plantings maximize the benefits of companion planting with arugula. Arugula is ideal for intercropping, where it is planted as a quick-maturing “filler” crop between rows of slower-growing vegetables like tomatoes or peppers. Since arugula is harvested within a month, it utilizes the space before the main crop requires the full area for maturity.
To mitigate heat stress and prevent bolting, position taller shade providers on the south or west side of the arugula patch. This placement blocks the most intense afternoon sun while still allowing adequate morning light exposure. Timing can also be managed through succession planting. This involves immediately sowing a fresh batch of arugula seeds in the space vacated by an early-maturing companion, such as radishes, allowing for a continuous harvest throughout the cool season.