Arugula in Zone 6B — Texas

Arugula, with its peppery bite, is a fantastic addition to any Texas garden. It's quick to mature, versatile in salads and cooked dishes, and surprisingly rewarding to grow yourself. Plus, you can plant it in both spring and fall, extending your harvest in our long growing season.

The Texas climate can be unpredictable, with periods of extreme heat and variable rainfall. But with some attention to timing, you can easily enjoy a steady supply of fresh arugula from your garden. Our 230-day growing season gives us plenty of opportunity to get it right.

Starting arugula indoors is an option, especially if you want a very early spring harvest, but direct sowing is generally easier. If you choose to start indoors, aim for mid February through early March, about three weeks before you plan to transplant. Use seed trays or small pots filled with seed-starting mix and keep them in a warm location with plenty of light – a sunny windowsill or under grow lights works well.

Bottom watering is a great way to keep the soil consistently moist without disturbing the delicate seedlings. Given our early spring warmth, you’ll need to watch for rapid growth and be ready to transplant promptly.

Transplant your arugula seedlings outdoors from mid March through late April. Before transplanting, harden them off by gradually exposing them to outdoor conditions for about a week. This helps them adjust to the Texas sunshine and temperature swings.

Space the seedlings about 6 inches apart in well-drained soil. Keep an eye on the weather forecast; a late freeze can still happen, so be prepared to cover your young plants if needed.

Direct sowing arugula is a simple and effective method for Texas gardeners. Sow seeds directly into the garden from late February through mid September, ensuring the soil temperature is consistently above 40°F. Prepare the soil by loosening it and removing any rocks or debris.

Sow the seeds about ¼ inch deep and 6 inches apart. Arugula is fast-growing, but it tends to bolt in the Texas heat, so focus on planting during cooler periods.

Arugula needs consistent moisture, but it doesn’t like to be waterlogged. In Texas, a good rule of thumb is to water deeply about once or twice a week, depending on rainfall and temperature. Stick your finger about 2 inches into the soil; if it feels dry, it's time to water.

During the hotter parts of the year, you may need to water more frequently. Aim for about 1 inch of water per week. Water at the base of the plants to avoid wetting the leaves, especially with our variable humidity, which can encourage fungal diseases.

Signs of underwatering include wilting and yellowing leaves, while overwatering can lead to root rot. A layer of mulch, like shredded leaves or straw, can help retain moisture and keep the soil cool, which is especially important during the Texas heat.

You can expect your first arugula harvest about 40 days after planting, typically from early April through mid November in Texas. Harvest the young leaves when they are 2-3 inches long for a milder flavor. Larger leaves will have a more pronounced, peppery taste.

To harvest, simply snip off the leaves with scissors or pluck them by hand, being careful not to damage the plant's central stem. Regular harvesting encourages continued production. As the first frost approaches in early November, harvest any remaining leaves to enjoy before the cold weather sets in.

Here are some common problems you might encounter growing arugula in Texas:

Flea Beetles

• What it looks like: Tiny round holes (shot-hole pattern) in the leaves, especially on young seedlings. You might also see small, dark beetles that jump when disturbed.
• What causes it: These small jumping beetles feed on the leaves, causing the most damage to small, young plants.
• How to fix/prevent it: Use row covers to protect seedlings. Delay planting until plants are larger and more resilient. You can also try coating the leaves with kaolin clay or spraying with neem oil. Interplanting with basil or catnip can also help deter them.

Bolting in Heat

• What it looks like: The plant sends up a flower stalk, and the leaves become tough and bitter.
• What causes it: Arugula is a cool-season crop and will bolt (go to seed) when temperatures rise consistently above 80°F.
• How to fix/prevent it: Time your plantings for cooler weather in spring and fall. Choose bolt-resistant varieties. Provide shade during warm spells and mulch to keep the soil cool. Harvest regularly to encourage leaf production before bolting progresses.

Aphids

• What it looks like: Clusters of tiny, soft-bodied insects (green, black, or white) on stems and leaf undersides. You might also notice a sticky honeydew residue and curled or distorted new growth.
• What causes it: These sap-sucking insects reproduce rapidly, especially in warm weather. Ants may also farm them for the honeydew they produce.
• How to fix/prevent it: Knock aphids off with a strong water spray. Encourage natural predators like ladybugs and lacewings. Use insecticidal soap for heavy infestations or apply neem oil systemically. Avoid excess nitrogen fertilizer, as it can attract aphids.

Downy Mildew

• What it looks like: Yellow patches on leaf tops with fuzzy gray-purple growth on the undersides. Leaves will eventually brown and die from the bottom up.
• What causes it: This oomycete pathogen spreads in cool, humid conditions via wind-carried spores.
• How to fix/prevent it: Remove affected leaves immediately. Improve air circulation around the plants. Water at the base, avoiding overhead watering. You can also use copper-based fungicides for prevention and plant resistant varieties if available.

Texas Specific Challenges: The hot-to-extreme heat during the Texas summer can cause arugula to bolt quickly, so timing your plantings is crucial. Variable humidity can also contribute to fungal diseases like downy mildew. Unpredictable rainfall means you need to be vigilant about watering, ensuring the plants receive consistent moisture without becoming waterlogged.

Arugula benefits from companion planting. Lettuce and spinach make good neighbors, as they have similar growing requirements and don't compete for the same nutrients. Carrots and beets help to loosen the soil, which aids arugula's root growth. Onions can deter pests, protecting your arugula crop.

Avoid planting arugula near strawberries, as they can attract pests that also affect arugula. Keep your arugula patch happy by choosing the right companions for our Texas garden.