How to Grow Arugula

By: Angela Judd | December 10, 2020

Learning how to grow arugula is simple. It doesn’t require much room and grows well in almost any container. Arugula is a fast-growing, cool-season green known for its peppery flavor. The tender leaves are delicious added to salads or piled on top of pizza.

Keep reading for the planting dates for growing arugula in the low desert of Arizona. There is also a bonus tip at the end for growing arugula in containers.

5 Tips for How to Grow Arugula

1. Plant arugula at the right time

Arugula prefers cooler temperatures. Prolonged warm temperatures cause arugula to bolt and become bitter. It doesn’t like the heat, but arugula tolerates a little frost.

In most areas, plant arugula after the last spring frost date. Ideal soil temperature for planting is 45°F – 65°F. Arugula grows best in temperatures between 45°F – 55°F.

In the low desert of Arizona:

Start seeds indoors: September – January

Plant seeds outside: August 15 – January

Plant transplants outside: October – February

Succession plant arugula every 2-3 weeks during the growing season for a continual harvest of the leaves. Learn more about succession planting in this guide.

2. Plant arugula correctly

Arugula grows quickly and does best planted from seed. Arugula grown from transplant often bolts more quickly than arugula grown from seed.
Plant arugula seeds 1/4 inch deep and 1-2 inches apart. Keep soil moist until the seeds sprout.
Thin little seedlings (when they are several inches tall) to 2 to 3 inches apart. Thin seedlings to 6 inches apart for larger plants. Arugula thinnings are tender and delicious.
Arugula can be grown in full sun during cool weather. It also tolerates partial shade (4-6 hours sun).
Beets, carrots, cucumbers and onions are good companion plants for arugula.

For square foot gardening, plant 4 arugula per square foot.

3. Try different varieties of arugula

Astro arugula has a mild flavor and is somewhat heat-tolerant.

It alian arugula (also called Rocket or Roquette) is the most common variety of arugula.

Wasabi arugula a wild arugula with a taste similar to wasabi.

Heirloom Rustic arugula is a slow-growing (slower to bolt) more intensely flavored arugula.

4. Don’t allow arugula to dry out

Arugula has a shallow root system and requires frequent watering. Dry conditions cause arugula to become bitter and/or bolt.

To avoid problems with disease, try not to get water on the leaves when watering. Water in the morning if possible.

WHAT IS BOLTING? When a plant is under stress from lack of water, temperature, or other environmental factors, the plant may prematurely produce a flowering stem that produces seeds. Once a plant bolts, it often becomes inedible and bitter. Plants that may bolt include lettuce, cilantro, spinach, arugula, and celery.

5. How to grow arugula? Harvest arugula often

Young arugula leaves have a mild, peppery flavor which gets stronger as the leaves grow larger.

Pick off the outer leaves of arugula. Picking leaves regularly encourages growth. Learn more about cut-and-come-again harvesting in this guide.

Arugula leaves are ready to harvest 35-50 days after planting from seed. Begin harvesting arugula once the leaves are 4 to 6 inches long.

The flowers of bolting arugula are edible and add a distinctive peppery flavor to dishes. Arugula flowers develop into seed pods. Cut back arugula flowers before seeds form if you do not want arugula to reseed in your garden.