Arugula in Zone 8B — Florida

Arugula is a fantastic addition to your Florida garden, offering a peppery kick to salads, sandwiches, and even pizzas. Its quick growth and cool-season preference make it a satisfying crop to grow here, especially when our typical summer crops are struggling in the heat.

Florida gardening calendar is different, and summer is the slow season. While we face challenges like extreme humidity and sandy soil, timing your arugula plantings right allows you to enjoy a continuous harvest during our cooler months. With our 303-day growing season, you can plant in fall and harvest in winter.

Starting arugula indoors in Florida isn't essential, as it direct sows so easily, but it can give you a head start. If you want to get a jump on the season, aim to start your seeds indoors from early to late January, about three weeks before you plan to transplant.

Use seed trays or small pots filled with a good seed-starting mix. Keep them warm and provide plenty of light, either from a sunny window or a grow light. Bottom watering is a good way to keep the seedlings evenly moist without encouraging fungal diseases, which can be a problem with our high humidity. Remember our spring start is reversed here, so getting a head start gives you an edge.

Transplanting arugula seedlings outdoors in Florida should happen from early February through mid March. Before you move them permanently, harden them off by gradually exposing them to outdoor conditions for about a week.

Space your seedlings about 6 inches apart in well-drained soil. Keep an eye on the weather forecast – those late cold snaps can still happen, so be prepared to cover your seedlings if temperatures dip near freezing.

Direct sowing arugula is the easiest way to grow it in Florida. Since it's fast-growing, you can sow seeds directly into your garden bed from mid January through late October.

Prepare your soil by loosening it and removing any rocks or debris. Sow seeds about ¼ inch deep and 6 inches apart. Arugula needs cool weather to thrive, so avoid planting during the hottest parts of the year to prevent bolting.

Arugula needs consistent moisture, but avoid waterlogging the soil, which can lead to root rot in our humid climate. Aim to keep the soil consistently moist to the touch.

During our drier spring and fall months, you'll likely need to water deeply about once a week, providing around 1 inch of water. Use the "finger test" – stick your finger about 2 inches deep into the soil. If it feels dry, it's time to water. In our wet-summer months, rainfall may be sufficient, but monitor the soil moisture regularly. It is best to water at the base of the plant to avoid wetting the leaves and promoting fungal diseases in our humid environment.

Wilting leaves are a sign of underwatering, while yellowing leaves can indicate overwatering. Adding a layer of mulch, like pine straw or wood chips, can help retain moisture in the soil and suppress weeds.

You can expect your first arugula harvest in late February through late December, about 40 days after planting. Start harvesting when the leaves are 2-3 inches long for a milder flavor. Larger leaves will have a more intense, peppery taste.

To harvest, simply snip off the outer leaves with scissors or your fingers, leaving the inner leaves to continue growing. This encourages continuous production throughout the season. As the first frost approaches in mid- December, you can cover your plants to extend the harvest a bit longer, but arugula is best enjoyed during our cooler months.

Flea Beetles

• What it looks like: Tiny round holes (shot-hole pattern) appear on the leaves, especially on young seedlings. You might also see small, dark beetles jumping around when disturbed.
• What causes it: These small jumping beetles feed on the leaves. They are most damaging to small, young plants.
• How to fix/prevent it: Use row covers to protect seedlings during their vulnerable stage. You can also delay planting until plants are larger and more resilient. Coating the leaves with kaolin clay can deter them. Neem oil spray can also help. Interplanting with basil or catnip may also help repel them.

Bolting in Heat

• What it looks like: The arugula plant sends up a flower stalk, and the leaves become tough and bitter. The harvest quality declines significantly.
• What causes it: Extended warm temperatures, a common occurrence in Florida, trigger bolting. Arugula prefers cooler temperatures.
• How to fix/prevent it: Time your plantings for the cooler parts of the year (spring and fall). Choose bolt-resistant varieties if available. Provide shade during warm spells with shade cloth. Mulch around the plants to keep the soil cool. Harvest frequently to encourage continued leaf production before bolting progresses.

Aphids

• What it looks like: Clusters of tiny 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: Rapidly reproducing, sap-sucking insects. Populations explode in warm weather.
• How to fix/prevent it: A strong spray of water from the hose can knock them off the plants. Encourage beneficial insects like ladybugs and lacewings, which are natural predators. Insecticidal soap can be used for heavy infestations. Neem oil also works well. Avoid excess nitrogen fertilizer, as it attracts aphids.

Downy Mildew

• What it looks like: Yellow patches appear on the tops of the leaves, with fuzzy, gray-purple growth on the undersides. The leaves will eventually brown and die from the bottom up.
• What causes it: A fungal pathogen that spreads in cool, humid conditions through wind-carried spores.
• How to fix/prevent it: Remove affected leaves immediately. Improve air circulation around the plants. Water at the base of the plant, avoiding overhead watering. Copper-based fungicides can be used for prevention. Plant resistant varieties if available.

Florida Specific Challenges: Our hot heat, very-high humidity, and wet-summer rainfall create the perfect environment for fungal diseases and pests to thrive. Choose disease-resistant varieties, ensure good air circulation, and monitor your plants regularly to catch problems early. Remember that nematode-resistant varieties are important for many crops here, but arugula is fast, so they don't usually affect it much.

Arugula benefits from companion planting, especially in our Florida gardens. Planting lettuce and spinach nearby helps create a cooler, moister microclimate that arugula enjoys. Carrots and beets are also good companions, as they don't compete for the same nutrients and can help loosen the soil. Onions can help deter pests that might bother your arugula.

Avoid planting arugula near strawberries. Strawberries are susceptible to root-knot nematodes, which can be a problem in our sandy Florida soils, and planting them together can increase the risk of infestation.