While the ancient Romans and Egyptians thought the oil and foliage of arugula to be an aphrodisiac, most people nowadays enjoy arugula added to sandwiches and salads for a bit of tangy, spicy taste or used as a topping on pizza. It is also commonly found as a component of mesclun salad mixes.
Named in the Old Testament, arugula has been around forever or almost, and it is believed that cultivation began as far back as the 6th century BC.
This leafy green is a self-seeding, annual, cool-season crop that is a rapid grower. Botanically known as Eruca sativaor Eruca vesicaria, it is commonly called rocket, arugula, rucola, rucoli, or roquette.
Native to warmer Mediterranean regions like Morrocco, Portugal, Turkey, and Italy, it also calls western Asia home. Used medicinally, even to this day in India, West Asia, and Pakistan. Arugula seeds are pressed for oil that is then used for inflammatory skin conditions, dandruff, killing lice, and stimulating hair growth. It is a member of the Brassicaceae or mustard family and is related to vegetables like broccoli, cabbage, and kale, but with a tangier taste than most greens.
It can be planted in USDA hardiness zones 3 through 11 in either early spring or at the beginning of autumn and is generally ready to be harvested in as little as six to eight weeks after sowing seeds. Germination takes place quickly in cool soil and this plant can even resist a bit of frost, although row cover protection will offer better results. Arugula also makes a great companion crop because it has very shallow root systems so it will not require a lot of space and can be sown around crops that are slow-growers.
Planting Arugula
This is an easy-going kind of green as it will tolerate various conditions. It prefers a soil bed that is rich in nutrients and that drains well. If you have the possibility, you may want to amend the soil with organic matter when tilling before sowing seeds. If desired, it can be successfully cultivated in containers and raised garden beds. Soil pH should measure between 6 and 7 for a quality harvest.
Originating in the Mediterranean, Arugula likes exposure to full sunlight, so select a location for your plants that receives six or more hours of sunlight daily. This green can grow in partial shade, but the results will not be as satisfactory. Also, do not plant arugula where other members of the Brassicaceae have recently been cultivated, as diseases or pests may still be present in the soil bed. Crop rotation is a plus.
If you are planting in a warmer climate, look for a cultivar that is heat-resistant.
When to Plant Arugula
Baby Arugula seeds can be sown when the ground temperature is stable at 40°F. Once your soil bed can be tilled, go ahead and sow. If you prefer a winter harvest, sew at the end of summer or the beginning of autumn.
How to Sow Arugula Seeds
Arugula seeds can be sown in rows that are spaced ten to twelve inches apart. Seeds should be sown with an inch of space between them and about a quarter of an inch deep. Seeds will germinate in approximately a week unless your climate is cooler. In this case, it may require a few more days. Before sowing, you can speed up the germination process by soaking arugula seeds in water for several hours. If you would like a prolonged harvest of arugula, sow seeds every fifteen to twenty days to keep the greens coming.
Arugula Plant Care
Overall, Arugula requires little care. It needs soil to be maintained consistently moist. This is very important when the weather warms up, otherwise, your plants may bolt and immediately produce flowers and seeds without having developed their foliage.
Once seedlings have appeared, thin them so that they are spaced approximately six inches apart. The seedlings you remove can be added to salads. If you are planting arugula in warmer weather, do consider providing some shade to prevent heat stress and bolting.
Arugula Pests and Diseases
Like all leafy greens, there are inevitably pests that will find your greens just as appealing as you do. In the case of arugula, you may find:
·        Birds
Birds enjoy nibbling on fresh greens. The best options for protecting your cultivation are row covers or netting.
·        Cabbage Loopers
These are small green caterpillars that will munch on leaves and will grow larger the more they eat. Remove them manually and scatter diatomaceous earth around plants. Use floating row covers as prevention.
·        Cabbage Worms
Foliage will have big uneven holes or even appear skeletonized. Worms will leave dark green excrement on plants and may lay eggs, that are yellowish in color on the undersides of leaves. Remove any worms you find manually and grow companion plants that worms don’t enjoy like thyme. You can also spray plants with Bacillus thuringiensis, which is a beneficial bacterium.
·        Flea Beetles
These critters will leave lots of tiny holes in foliage. One of the most efficacious methods for avoiding beetles is the use of row covers. You can also mulch heavily.
·        Slugs
Slimy grey slugs or soft brown mollusks may eat large holes in foliage. You can remove these manually or create traps filled with beer. Bury the cups in the soil with the rim just above the surface. Slugs find beer attractive and will hopefully fall in. Another option is scattering diatomaceous earth at the base of the plant.
Diseases
·        Downy Mildew
This fungus leaves angular yellow spotting on foliage that later turns brown. Cottony growth will be found on leaf undersides and will be white, grey, or purplish in hue. Leaves will suffer distortion during growth and drop. All infected leaves should be removed. Avoid overhead watering and make sure your plants enjoy good air circulation. You can also select to grow varieties that are resistant to Downy Mildew.
·        Leaf Blight
Wet brown spots or yellowing foliage are generally indications of Leaf Blight which is a bacterial infection. Infected plants should be removed and destroyed. Water plants at the base instead of overhead as a preventative measure.
·        White Rust
White Rust is also a fungal infection that forms blisters on leaf undersides that will be a chalky-white hue.You may also see yellowish-green spots that are tiny or again blisters on the top surfaces of foliage. Check stems that may also be infected. All infected plants should be destroyed. Consider cultivating resistant varieties and use crop rotation regularly.
Harvesting Arugula
Arugula is best enjoyed when harvested while still young. Older leaves can have a stronger taste and be tougher to chew. Foliage should be harvested when it reaches approximately three inches in length. You can harvest individual leaves or pull up entire plants for consummation. The white blooms produced by the plant can be eaten as well. Ideally harvest leaves in the early morning or evening to avoid any wilting if the sun is hot.
Storing Arugula
Fresh arugula leaves can be stored in the refrigerator for up to ten days. Place them inside the crisper drawer after wrapping leaves in cloth or paper towels and putting them in a perforated plastic bag.
They can also be washed and chopped into tiny pieces, and then placed in ice cube trays. Cover the chopped arugula with a little olive oil and then freeze your arugula cubes. They can be removed as needed and used in soups, sautés, and even scrambled eggs for an extra bit of tangy flavor.