Bell Peppers in Zone 9B — Desert Southwest

Bell peppers are a fantastic addition to any Desert Southwest garden. Their sweet flavor and crisp texture make them a versatile ingredient in countless dishes. Plus, there's nothing quite like the satisfaction of harvesting your own colorful peppers, especially when our long growing season allows for a generous spring and fall harvest.

Growing peppers here does come with its challenges, like extreme heat and alkaline soil. However, with careful timing and a few desert-gardening tricks, you can successfully grow bell peppers and enjoy a bountiful harvest. Our 313-day growing season gives us plenty of opportunity to get it right.

Starting bell pepper seeds indoors is the way to go in our climate. Begin in mid- December through early January, about eight weeks before you plan to transplant them outside. This gets you a jump start, allowing peppers to mature before the worst of the summer heat.

Use seed trays with a good seed-starting mix. Provide warmth with a heat mat and plenty of light with grow lights. Bottom watering is ideal to keep the soil consistently moist without damping off. Remember, spring comes early here, so getting a head start indoors is key.

Transplant your bell pepper seedlings outdoors in mid February through mid March. Before planting, harden them off by gradually exposing them to outdoor conditions for about a week. This prevents shock from the intense Desert Southwest sun.

Space your plants 18-24 inches apart in well-draining soil. Keep an eye on the weather forecast. Occasional cold snaps can still happen, so be ready to cover your seedlings if temperatures dip unexpectedly.

Consistent watering is essential for bell peppers in our arid climate. Uneven moisture leads to blossom end rot and thin-walled fruit. The key is to find that balance, especially with the monsoon season's unpredictable bursts of moisture.

During the spring growing season, check the soil moisture using the "finger test" – stick your finger about two inches deep into the soil. If it feels dry, it's time to water. Aim for about 1-2 inches of water per week, watering deeply at the base of the plant rather than overhead to minimize fungal issues in our low humidity. During the extreme heat of summer, increase watering frequency as needed.

Wilting leaves indicate underwatering, while yellowing leaves suggest overwatering. Apply a layer of organic mulch, like compost, to help retain moisture and regulate soil temperature. This is especially helpful in our alkaline soil.

While bell peppers have a bush-like growth habit, the weight of the fruit can sometimes cause branches to break or the entire plant to topple over. Providing support is a good idea, especially as harvest time approaches.

A simple stake and some garden twine work wonders. Install the stake near the plant at transplanting time to avoid disturbing the roots later. As the plant grows and the peppers develop, gently tie the branches to the stake for support.

Pruning bell peppers isn't strictly necessary, but it can improve airflow and fruit production. Pinch off any early flowers that appear before the plant is well-established. This encourages the plant to focus on vegetative growth first.

Remove any peppers that touch the ground to prevent rot. Prune out some of the interior branches to improve air circulation and sunlight penetration. As the first frost approaches in mid- December, prune off any new flowers to encourage the plant to ripen existing fruit.

You can expect your first harvest of bell peppers in late April through mid June, about 70 days after transplanting. Bell peppers can be harvested at the green, immature stage, but their flavor is sweetest when they turn red, yellow, or orange.

Gently twist or cut the pepper from the plant using pruning shears. Regular harvesting encourages the plant to produce more peppers. As frost threatens, harvest all remaining peppers, even if they are green. They will ripen indoors if stored in a paper bag with an apple or banana.

Bell peppers can encounter a few problems in the Desert Southwest. Here's how to tackle them:

• Blossom End Rot
• What it looks like: A sunken, dark brown or black leathery patch on the bottom of the pepper.
• What causes it: Inconsistent watering leads to calcium deficiency. Our dry climate makes this a common issue.
• How to fix/prevent it: Water consistently and deeply. Mulch heavily to maintain even soil moisture. Remove affected fruit.
• Blossom Drop
• What it looks like: Flowers fall off without setting fruit. Small fruit yellows and drops.
• What causes it: High temperatures and low humidity stress the plant. Common during our extreme summer heat.
• How to fix/prevent it: Provide afternoon shade during extreme heat. Keep plants well-watered. Hand-pollinate if necessary.
• Aphids
• What it looks like: Clusters of tiny green, black, or white insects on stems and leaf undersides. Sticky honeydew residue.
• What causes it: Rapid reproduction in warm weather. They love our long growing season.
• How to fix/prevent it: Strong water spray to knock them off. Introduce ladybugs. Insecticidal soap or neem oil for heavy infestations.
• Sunscald
• What it looks like: White, papery patches on fruit exposed to direct sun.
• What causes it: Intense, direct sunlight. A real threat in our desert environment.
• How to fix/prevent it: Don't over-prune. Use shade cloth during the hottest part of the day.

Desert Southwest Specific Challenges: The extreme heat, arid humidity, and occasional monsoon rains of the Desert Southwest create unique challenges for bell pepper growers. Consistent watering is crucial to combat blossom end rot and blossom drop. Shade cloth is essential for summer survival.

Companion planting can help your bell peppers thrive in the Desert Southwest.

• Good companions: Tomatoes provide shade, basil repels pests, carrots loosen the soil, onions deter insects, and spinach provides ground cover to retain moisture. All these things help bell peppers handle our climate better.
• Bad companions: Avoid planting fennel, kohlrabi, and brassicas near bell peppers. Fennel inhibits growth, while kohlrabi and brassicas compete for nutrients in our already challenging soil.