How to Plant, Grow, and Care for Arugula

Growing arugula provides you with peppery flavor and an amazing source of vitamins A, C, and K. These tart-tasting leaves have become a signature part of cuisine. In a salad, bright green arugula leaves are a perfect addition for an added punch of flavor. And if you grow arugula at home, you’ll have a constant supply!

Historians believe that arugula was once referred to as “oroth,” a green leaf referenced in the Old Testament of the Bible. Indeed, this lovely plant was grown throughout the Mediterranean region during Roman times. Also popular during the Middle Ages in Britain, it was then referred to as rocket or garden rocket. The French called it roquette, possibly inspiring the name of rocket.

It’s a fascinating herb; you’ll love growing and consuming these salad greens!

What is Arugula?

Most commonly, Eruca vesicaria or Eruca sativa are the botanical names for arugula. However, about 40 different botanical names are used over time to refer to it. If this is confusing, you can refer to it as garden rocket, roquette, colewort, rugula, rucola, or even arugula.

Native Area

Its origins are in the Mediterranean, stretching from Turkey, Syria, and Lebanon on the eastern edge all the way west to Portugal and Morocco. Eruca sativa stretches into Southern Asia. A member of the Brassicaceae or mustard family, it shares its genetics with other cruciferous vegetables like kale, cabbage, mustard, and broccoli. Leaning more towards the peppery flavor of the mustard side of the family, they have become a popular salad green.

Characteristics

This leafy annual stays around a foot to two feet tall, although it ranges anywhere from eight inches to nearly 40″. The leaves are pinnate and often two to three inches long, attached to slender stems. They’re described as a longer, narrower lettuce leaf. Rocket produces inflorescences of white flowers with purplish veins running through them. As the flowers go to seed, they form long, tight seed pods. There is even a wild arugula cultivar which is heat tolerant.

Both the leaves and the arugula flowers are eaten. The edible seeds can also be pressed to make taramira seed oil instead. Some sources claim arugula was said to be an aphrodisiac by the Romans. It’s rumored to have been disallowed in monastery gardens because of this. However, lettuce was supposed to soothe one’s passions, and thus arugula was blended into mixed salads for this purpose!

Planting

For most growers, two seasons are ideal to grow arugula. Plant arugula seeds as soon as the soil can be worked in early spring for an early-year crop. When it dies back in late summer, wait for the weather to cool and replant in the fall for a second harvest. As soon as the soil freezes, it will die back again, so harvest before frosty conditions come.

If you want a continual harvest, sow seeds every two to three weeks throughout the season. You’ll need an area of the yard protected from extreme heat or cold but that gets at least partial sun. This herb is forgiving of somewhat shady conditions as long as there’s bright ambient light, but it won’t perform well in scorching heat.

Alternatively, grow arugula in containers. It grows well both indoors and out as long as it has enough bright light.

Sow seeds about a quarter of an inch deep and about an inch apart. Space rows at least ten inches apart for good outward development and to allow ample room for healthy root development. Once seedlings emerge, it’s time to thin seedlings. Keep arugula four inches apart if you grow arugula for young leaves, six inches for mature leaves or seeds.

It is possible to broadcast-sow arugula, with or without other leafy greens, to create thick and lush raised beds. This works best for leaf lettuce, mustards, or other related herbs. Thin seedlings appropriately and harvest from these beds regularly to allow for more development. Starting seeds in advance and transplanting young seedlings out is not impossible, but it may be tricky. It’s easier to sow where you plan to have your arugula growing.

Arugula also makes excellent microgreens.

How to Grow

So now that you know how planting arugula works, what conditions do you need to grow it in your garden for the best spring or fall harvest? Let’s discuss how to grow your own arugula!

Light

Full sun to partial shade is best when you grow arugula. Six to seven hours of daily sunlight is required for them to grow. They can accept indirect but bright lighting in lieu of direct full sun, making them an excellent choice for some of your partially-shaded garden areas.

Water

When growing arugula, the best method is to keep the soil evenly moist. Water in the morning, as this allows plenty of time for leaf surfaces to dry out in the sun. Mulching the garden can also keep the soil consistently moist and reduce watering frequency. A drip irrigation system or soaker hose underneath the mulch can make watering easy.

Soil

Humus-rich, well-drained soil is what your herbs will prefer. However, they’re tolerant of a wide range of garden soil types as long as they retain moisture. If you have sandy soil, amend it with compost and horse manure or cow manure to provide extra moisture retention. Worm castings can also be applied for additional moisture retention.

Hard-packed clay should be broken up by a lot of compost or manure as well. This will reduce the likelihood that it will become hard and prevent easy root development. The pH level for your arugula should be neutral, with a 6.0-7.0 range considered ideal. But they will tolerate slight acidity to slight alkalinity as well.

Temperature

A cool-weather herb, arugula greens develop best in temperatures ranging between 45-65°F (7-18°C). Once the weather in the garden reaches the 80s (around 27°C) or higher, your plant bolts to flower and seed production. Try a slow bolt seed. When it produces seed, the plant dies. Arugula is tolerant to mild frosts but can be damaged and die back in true freezing conditions. If you’re in a mild climate, grow arugula all winter long to have a constant supply.

Fertilizing

Provide a balanced fertilizer to ensure they have what they need to develop healthy young leaves. A dry granular formula can be applied once or twice where arugula grows during the growing season (whether spring or fall). Alternately, use diluted liquid fertilizers at the base as needed to keep the fresh greens healthy.

Maintenance

Arugula doesn’t need pruning, as you’ll harvest leaves regularly to eat it! If you do end up with too much to eat, pinch off any yellowing leaf material. Ensure that your older herbs have space between them, at least a few inches apart, to allow for good airflow around them. You may encounter various disease issues if they’re clustered too closely together.

At the end of the growing season, in late summer or fall, your herbs will die due to summer heat or freezing conditions in the winter. At those times, remove them and prepare the bed for a different crop, or cover crop until it’s time to sow again.

Propagation

Arugula seeds from unreliable sources may be carriers of some fungal diseases. Purchase seeds from reliable sources or treated them with fungicides. This prevents fungal issues spreading to your soil. Since this is a herb that mostly thrives in a mild climate, start it from seed. While it is possible to grow arugula from just the base and shallow root system, it will be stressed from the loss of its leaves and may bolt. Set arugula seeds one to two inches apart.

Harvesting

Now you’ve got an abundance of healthy young leaves. So how do you harvest these arugula leaves and keep them fresh?

Whether you’re harvesting arugula in spring or fall, you’ll use the same methods. Harvest the outer leaves at no more than a third of each herb if you want to use a cut-and-come-again method to extend that plant’s productivity for a longer period of time. A younger and smaller herb yields softer and more tender leaves than the older ones. These have a mild flavor.

You can harvest arugula when it’s very young for baby greens, and they’re a great addition of peppery flavor to any salad. As the arugula leaves get older, their mild flavor is more pronounced and reminiscent of mustard greens with a slightly peppery bite.

If your herb has flowered, the outer leaves will be more bitter. They may also be tough, but they’re still edible if you want to get one last meal from the herb. Looking to harvest arugula seeds for planting or seed oil? Wait for it to flower and form seed pods. Once those dry out, cut off the pods and keep them somewhere to completely dry out before popping them open to save the seed.

Storage

Rinse off your fresh harvest to remove garden pests or dirt, and blot all leaf surfaces dry with a paper towel. Then, use a long strip of paper towel and lay your arugula leaves on it, gradually rolling them up into a neat bundle with all the tender leaves surrounded by the towel. Moisture is the enemy when storing any greens, and this reduces the likelihood of condensation forming.

Place your rolled-up arugula into a storage bag or container in the crisper drawer of the refrigerator. Unfortunately, there aren’t viable ways to provide long-term storage for these greens that don’t make them unappetizing or cause them to lose flavor, so stick with fresh.

Common Problems

Like most salad greens, you are going to find pests trying to snack on them, or disease issues on leaf surfaces. Let’s talk about any problems you may face!

Growing Problems

Most of the non-pest or disease-related issues with arugula revolve around the weather. It’s a cool-weather crop, so unless you are growing a heat-tolerant variety, once the temperature goes up it will bolt and go to seed quickly. To get an early-season crop, plant arugula seeds in early spring. They’ll need 40-60 days to fully mature, but you can begin cut-and-come-again harvesting earlier than that.

Pests

The worst pest of arugula for many is the flea beetle. These hungry pests chew holes in the arugula leaves. Their larvae live in the soil and gnaw on the shallow root system. It’s essential to prevent these from taking hold in your garden. Neem oil is an effective organic treatment against flea beetles. Floating row covers keep them out of your herbs, too.

Aphids are the other major issue you’ll encounter. The cabbage aphid, green peach aphid, and potato aphid are all drawn to arugula. These garden pests spread disease and suck the moisture out. Neem oil or insecticidal soap are effective control methods.

Cabbage loopers are green caterpillars that feast on fresh leaves of arugula, putting holes in them and leaving small poppy-seed-like frass behind where arugula grows. Hand-pick them from your own garden or treat them with BT spray. Floating row covers are a great preventative measure.

Diseases

One of the most common diseases on arugula is downy mildew. This causes yellowish spotting on the upper surfaces of the leaf, with a grey mildew or mold-like substance underneath. Prevent the development of downy mildew with regular applications of neem oil.

When the temperature is warm, and there’s a lot of humidity in the air, plants risk developing bacterial leaf spot. Usually a Pseudomonas species, this bacteria has no organic cure. Remove infected leaves. If the problem persists, remove infected plants entirely.

Finally, damping off caused by Pythium fungi in the soil can be an issue for young arugula plants. Grow in sterile soil when possible to reduce the risk of planting arugula in contaminated soil. If you’re growing in an older bed, pre-treat the seeds and planting area with beneficial mycorrhizae to reduce the likelihood of the pythium attacking. Remove those that show signs of damping off. Avoid growing the leaves in areas where this has happened previously.

Frequently Asked Questions