Bell Peppers in Zone 7A — Pacific Northwest

Bell peppers are a rewarding addition to any Pacific Northwest garden. Their crisp, sweet flavor shines in summer salads, stir-fries, and stuffed pepper recipes. The satisfaction of harvesting colorful, homegrown peppers after our cool spring is truly special. Plus, cool nights in the PNW actually improve the flavor!

While our region isn't known for blistering heat, bell peppers thrive here with a little planning. Our 183-day growing season is long enough to bring peppers to maturity if you start seeds indoors and provide a bit of extra warmth. Don't let our reputation for "mild summers" scare you off – you can absolutely grow delicious peppers in your garden.

Starting bell pepper seeds indoors in early to late March gives them a head start on our relatively short growing season. Peppers need warmth to germinate, so use a heat mat under your seed trays and aim for a soil temperature around 80-85°F. A sunny windowsill can work once seedlings emerge, but supplemental grow lights are ideal, especially during our often overcast spring days.

Use a well-draining seed starting mix and sow seeds about ¼ inch deep. Keep the soil consistently moist, but not soggy. Bottom watering is a great way to prevent damping off – simply set the seed trays in a shallow tray of water and let the soil absorb moisture from the bottom. Remember, spring can be slow to get going in the PNW, so patience is key!

Transplant your pepper seedlings outdoors from early May through early June, once the danger of frost has passed and the soil has warmed up. Before transplanting, it's crucial to harden off your seedlings. This involves gradually exposing them to outdoor conditions over the course of a week. Start with an hour or two of shade, then gradually increase the time and sun exposure each day.

Choose a sunny spot in your garden with well-drained soil. Space your pepper plants 18-24 inches apart. Be mindful of potential late-season cold snaps, especially in early May. If a frost is predicted, cover your transplants with row covers or blankets.

Consistent watering is essential for healthy bell pepper growth and thick-walled fruit in our dry summer months. Peppers are not drought-tolerant, and water stress can lead to blossom end rot and blossom drop. Aim to keep the soil consistently moist, but not waterlogged.

During our wet springs, you may not need to water at all, but once the dry summer months arrive, plan to water deeply about 1-2 inches per week. Stick your finger about 2 inches into the soil – if it feels dry, it's time to water. Watering at the base of the plant is best to avoid wetting the foliage, which can encourage fungal diseases in humid pockets.

Signs of underwatering include wilting leaves and dry, cracked soil. Overwatering can lead to yellowing leaves and root rot. A layer of mulch, such as straw or compost, helps to retain moisture, suppress weeds, and regulate soil temperature – all beneficial in our PNW climate.

While bell peppers have a bush-like growth habit, the weight of heavy fruit can cause branches to break or topple over, especially after a rain. Providing support is optional, but highly recommended, especially for larger varieties.

A simple stake and some garden twine are usually sufficient to keep your pepper plants upright. Install the stake at planting time, a few inches away from the main stem, and gently tie the plant to the stake as it grows. Cages also work well.

Pruning bell peppers isn't strictly necessary, but it can improve airflow and encourage larger, earlier fruit. Pinch off any early flowers that appear before the plant is about 12 inches tall to encourage stronger vegetative growth.

Remove any fruit that touches the ground to prevent rot. You can also prune out some of the interior branches to improve airflow and sunlight penetration, especially in dense plants. As the first frost approaches in mid- October, you can remove any remaining small flowers to encourage the plant to focus its energy on ripening existing fruit.

You can expect your first bell pepper harvest from mid July through late August, about 70 days after transplanting. Green peppers are technically immature, but perfectly edible. However, for the sweetest flavor, wait until the peppers turn their mature color – red, yellow, or orange.

Gently twist or cut the pepper from the plant, leaving a small piece of stem attached. Regular harvesting encourages continued production. As the first frost approaches in mid- October, harvest all remaining peppers, even if they are still green. Green peppers can ripen indoors if stored in a paper bag with an apple or banana.

Bell peppers can face a few common problems in the Pacific Northwest, but they are generally manageable with proactive care.

• 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 leading to a calcium deficiency. Common during our dry summer months if watering isn't regular.
• How to fix/prevent it: Water deeply and consistently, especially during dry spells. Mulch around plants to retain moisture. Remove affected fruit.
• Blossom Drop
• What it looks like: Flowers fall off without setting fruit. Small fruit yellows and drops.
• What causes it: Temperature stress, especially during our occasional heat spikes. Can also be caused by low humidity.
• How to fix/prevent it: Be patient – fruit set usually resumes when temperatures cool down. Provide afternoon shade during heat waves. Ensure consistent watering.
• 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 of sap-sucking insects. Can be prevalent in the PNW, but typically less severe than warmer climates.
• How to fix/prevent it: Knock them off with a strong spray of water. Encourage beneficial insects like ladybugs. Use 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 on fruit, often after pruning or leaf loss. More of a concern during heat waves.
• How to fix/prevent it: Avoid over-pruning. Use shade cloth during extreme heat.

Pacific Northwest Specific Challenges: Late blight can be a concern in our region, so choose blight-resistant varieties if possible. Our cool soil in spring can slow growth, so consider using black plastic mulch to warm the soil before transplanting. Even though our summers are mild, our dry-summer rainfall patterns mean consistent watering is vital. Also, watch out for slugs, especially on young plants!

Companion planting can help your bell peppers thrive in the Pacific Northwest.

Good companions for bell peppers include tomatoes, as they have similar growing requirements and can provide mutual support. Basil repels pests like aphids and whiteflies, while also attracting pollinators. Carrots improve soil drainage, and onions deter certain pests. Spinach can act as a living mulch, suppressing weeds and retaining moisture.

Avoid planting bell peppers near fennel, as it inhibits their growth. Kohlrabi and other brassicas (like cabbage and broccoli) compete for nutrients and can attract pests that also affect peppers.