The appetizing annual Arugula (Eruca sativa) is also commonly known as rocket salad or sometimes called colewort, garden rocket, gharghir, roquette, rucola, rucoli, and rugula. While often viewed as a lettuce, this sharp-tasting leafy green is actually is a member of the Brassicaceae family of plants (aka mustard plants) which includes some other well-known veggies such as kale and cauliflower. Arugula is known for its signature spicy, peppery flavor, but the heat intensity of this can vary depending upon variety.
This Mediterranean native has been grown since the turn of the first millennium and the seeds and leaves were once used as an aphrodisiac, with consumption often banned in monasteries. While it was not eagerly cultivated, tending to be picked as it grew wild, it did spread through Europe. By the 17th century, European settlers brought arugula to the Americas. As the next millennium began to roll around, arugula grew in popularity in many areas, especially in the US.
To grow arugula, it’s preferential to do plantings every few weeks to ensure a continuous harvest. When sowing seeds, do so as early as is feasible in the early spring or into the late fall. Arugula performs best in cool temperatures (60-65°F) and can even withstand light frosts. However, if you want to try growing in warmer conditions, the wild Italian arugula (Eruca selvatica) is more heat resistant than the common arugula.
Arugula is best planted in full sun, 6” apart in furrows 1-2’ apart, with ideal soils being loose and loamy at a pH of 6.0-7.0. However, it can tolerate a wide range of soil types as long as they provide adequate water holding capacity, but drain well. Due to its shallow root system, arugula requires consistent and frequent waterings to ensure a bountiful crop. Be sure to water the base of the plant and not the leaves. This will help reduce the likelihood of mildews, rusts, and blights. Rotating arugula with non-Brassicaceae family member plants, and avoiding overcrowding in your garden, can help reduce the likelihood of disease as well.
As your crop grows, garden pests can also afflict your arugula. Flea beetles are a common problem encountered when growing arugula, as are slugs, some caterpillars, aphids, and even birds. Floating row covers can help reduce pest populations, as can weed management and keeping an overall tidy garden. Planting trap crops, such as radishes, can deter pests away from your arugula. On the flipside, you can sow plants like yarrow and marigold to attract beneficial insects, such as predatory wasps and ladybugs to help control populations on unwanted insects.
Plant maturity is typically reached around 1-2 months. However, young leaves can be harvested in just a little over 2 weeks. Look for plants that have reached a height of 3-4” and begin your harvest to acquire a milder flavor leaf and/or to encourage continued and abundant leaf growth. As you notice a decrease in leaf growth, or in flavor, cease harvesting the smaller leaves.
When it comes time to harvest your arugula, pick leaves in the evening. If arugula is picked in the midst of the sun’s intensity wilting is likely to occur. Picking in the evening also prevents harvest during wet times and will help reduce soggy leaves. Once arugula is picked, store leaves wrapped in cloth or paper towels and placed in a perforated plastic bag. Keep the bagged arugula in the vegetable crisper drawer in your refrigerator for up to 10 days. However, note that some flavor may be lost after 5-6 days.
Arugula, with its powerful, punchy flavor offers quite a punch of nutrition too. In a one cup (20 grams) serving it offers 4 calories, 0 grams of fat, protein, and carbohydrates. Arugula is a good source of Vitamin K-1, and offers Vitamins A, C, B-2 (Riboflavin), B-9 (Folate), and minerals calcium, non-heme iron, magnesium, manganese, phosphorus, and potassium.
The nutritionally interesting thing about arugula is that it contains many compounds that boost our health in various ways. One thing arugula does is act as an anti-carcinogen. It does this due to the glucosinolates it possesses which are broken down into indoles, isothiocyanates in particular. These compounds help your body clean up cancerous cells before they can cause damage and help regulate hormone activity in order to reduce hormone-related cancer risks.
Arugula also acts as an anti-carcinogen due to the chlorophyll it contains. Dark leafy green vegetables like arugula contain chlorophyll, the pigment that gives plants their green color and helps them trap sunlight needed for photosynthesis. When we consume the chlorophyll from plants like arugula, it helps us block the cancer causing polycyclic aromatic hydrocarbons found in tobacco smoke and the heterocyclic amines found in meats cooked at high temperatures.
This zesty vegetable doesn’t stop there though. Along with other leafy greens, arugula contains an antioxidant known as alpha-lipoic acid (LA) that can reduce blood glucose levels, boost insulin sensitivity, and spoil oxidation’s good times by scavenging free radicals. LA can also decrease nerve damage in those with diabetes, improve mitochondrial function, slow the aging process, protect against neurodegenerative diseases, and chelate toxic metals by increasing intracellular glutathione levels.
One more benefit of arugula is that, like beets, it contains nitrates. Nitrates have gotten a bad rap due to the fact that they can trigger migraines in sensitive individuals, plus nitrates, once converted to nitrite can form nitrosamines, which are shown to be carcinogenic in animal studies. However, when this occurs the source of the nitrate is usually from processed meats, such as hotdogs and bologna. Arugula, like other nitrate containing produce, also contain vitamin C, which naturally inhibits the nitrosamines formation, and therefore arugula isn’t considered to be a carcinogen. In fact, high intakes of dietary nitrate can reduce blood pressure and decrease myocardial oxygen consumption during exercise, therefore improving athletic performance.
With its pungent taste, this lovely leafy green is often mixed raw into fresh garden salads or simply chilled on its own and drizzled with olive oil and lemon juice and sprinkled with a good hard cheese. Arugula also works well added atop pizzas after they’re done baking, or it can be cooked into omelets and sauces. Since arugula does have such a spicy flavor and fragrant scent I love creating a beautiful pesto with it. Here’s a recipe I like to make to top meat dishes that have understated flavors or even to use as an addition to potatoes or tomatoes.
Arugula Almond Pesto
1 cup arugula leaves
½ cup olive or avocado oil
1 cup properly soaked and toasted almonds
5 garlic cloves, mashed
½ cup freshly grated parmesan
Salt and freshly ground pepper to taste
Bring a large pot of water to a boil
Cook until bright green (~30 seconds)
Remove arugula and place in a bowl full of ice water for several minutes until cold
Drain and pat dry arugula
Place arugula and remaining ingredients in a food processor
Pulse until mixture is a coarse puree
Serve and enjoy!
While this isn’t your traditional pesto, as it uses almonds instead of pine nuts or walnuts, it still has a delightful pesto flavor and texture. And as you make this pesto, or any pesto, you may notice it changes color due to oxidation. The blanching of the arugula can help prevent this, as can adding an acid, such as lemon juice, to your mixture. You can also add ~ ¼ teaspoon of Vitamin C powder to your pesto to keep it bright green looking. Pouring a thin layer of olive oil over your pesto as you go to store can prevent air from reaching your pesto and will also minimize the color change. Even with all these tips to keep your pesto looking appetizing, the best way to have the brightest color and most flavor is to eat your pesto fresh, but if you do store it be sure to consume it within 1-2 days of making it.
With its outstanding flavor and multiple health benefits, arugula is a remarkable vegetable. It’s delightful growing in the garden and complimenting most any dish. The robust flavor and growing style of arugula makes this leafy green one of a kind and something you will want to grow every year. So, get your arugula growing my friends, and stay zesty!
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Levine, D. November 7, 2013. Regents of the University of California. University of California Master Gardeners of Napa County weekly column. Arugula, How to Grow and More. https://ucanr.edu/blogs/blogcore/postdetail.cfm?postnum=12026
Linus Pauling Institute. 2017. Oregon State University. Chlorophyll and Chlorophyllin. https://lpi.oregonstate.edu/mic/dietary-factors/phytochemicals/chlorophyll-chlorophyllin
Tibullo, D., et al. July 4, 2017. Inflammation Research. Biochemical and clinical relevance of alpha lipoic acid: antioxidant and anti-inflammatory activity, molecular pathways and therapeutic potential. Pages: 1-13. doi:10.1007/s00011-017-1079-6. https://link.springer.com/article/10.1007%2Fs00011-017-1079-6