Arugula, Eruca sativa, belongs to the Brassicaceae family. In the U.S. it is grown as an annual leafy green which provides a pungent bitter flavor used in salad mixes. In Europe, where it is most common, it is sold as an herb. Arugula prefers to grow during the cooler seasons of spring and fall but there are a few varieties that will tolerate the summer heat and are slower to bolt. Bolting is a term used meaning “to flower”. Some plants will “bolt” to flower quickly when conditions tell the plant to hurry to flower and make seed. Most cool season crops will bolt during warmer seasons. So planting arugula in June might not be the best time unless you are growing it to collect seed. It doesn’t overwinter, but its wild cousin, Sylvetta, Diplotaxis tenuifolia is slower growing and will grow well with winter protection such as in a cold frame. The leaves are more lobed and tastes less pungent than arugula, but is more highly sought after by chefs according to Johnny’s Selected Seeds.
Arugula should be directly sown in average garden soil, but you can start it indoors then transplant it outside. Eliot Coleman suggests planting seeds directly in the soil 1 inch apart in rows 6 inches apart. You can start arugula in a cold frame in late February. Ideal germination is about 65-68 degrees (Fahrenheit). Once germinated and the first true leaves are present, it will grow outdoors unprotected at 40 degrees. The best temperature range would be 50-65. Sowing every 2 to 3 weeks through the spring will ensure a continuous harvest.
To harvest, you just use a pair of scissors and cut at the soil line. You can have baby arugula in about 21 days, and full size leaves in about 40 days. It’s best to harvest first thing in the morning. Wash with cold water, and store any excess in the refrigerator. Using a salad spinner is really helpful in eliminating excess water which will improve the storage quality, but its best eaten fresh.
Plan your salad mixes by growing the leafy greens you love. Mix and match, add baby lettuces, spinach, and arugula. The possibilities are endless!