Pepperoncini in Zone 6B — Pacific Northwest

Pepperoncini peppers are absolutely worth growing here in the PNW. Their mild, slightly sweet heat is fantastic for pickling, adding to salads, or grilling. Plus, the satisfaction of harvesting your own peppers, especially with our cool nights enhancing their flavor, is hard to beat.

While our mild summers and wet springs can present challenges for warm-season crops, starting Pepperoncini indoors gives them a head start. With a little planning and attention to timing, you can enjoy a great harvest within our 162-day growing season.

Starting Pepperoncini indoors from mid-March through early April is essential to get a jump on our relatively short growing season. This gives you about 8 weeks to get your seedlings strong before transplanting. Use seed trays with a good seed-starting mix, and provide consistent warmth – a heat mat is really helpful, since our springs tend to be cool.

Consistent moisture is key, but avoid soggy soil. Bottom watering is an excellent trick: set your seed trays in a shallow dish of water and let the soil absorb what it needs. This encourages strong root growth and prevents damping off, which is a problem with our overcast spring days. Don't forget to give them plenty of light, too.

Transplant your Pepperoncini seedlings outdoors from mid-May through mid-June, after the last chance of frost has passed. It's important to harden off your seedlings for about a week before planting them in the ground. Gradually expose them to outdoor conditions, starting with just an hour or two of sunlight and wind each day, and slowly increasing the time.

Space the plants about 18-24 inches apart in a sunny spot with well-drained soil. Even in late May, the soil can still be cool, so you can warm it up by covering it with black plastic mulch a week or two before transplanting.

Pepperoncini peppers need moderate watering, especially during our dry summer months. While they aren't drought-tolerant, they also don't like to sit in soggy soil. During our wet springs, you might not need to water at all, but once the dry summer hits, you'll likely need to water a couple times a week, depending on rainfall.

The finger test is your best guide: stick your finger into the soil about 2 inches deep. If it feels dry, it's time to water. Aim for about 1 inch of water per week. Water at the base of the plant to avoid wetting the foliage, which can help prevent fungal diseases in our humid springs.

Slightly wrinkled skin on the peppers is normal and doesn't necessarily mean they're underwatered. Overwatering can cause yellowing leaves and root rot. Mulching around the base of the plants with straw or wood chips helps retain moisture and keeps the soil cool during those mild summer days.

Pepperoncini plants are generally compact and bushy, so they rarely need support unless they become heavily loaded with peppers. If you find your plants are starting to lean or topple over, a simple stake or tomato cage can provide the support they need.

Install the support at planting time to avoid disturbing the roots later. Gently tie the main stem to the stake with soft twine, or position the tomato cage around the plant. As the plant grows, continue to tie it to the stake as needed.

Training the branches to grow within the support structure can also help prevent breakage. This is especially helpful if you have a particularly prolific plant.

Pinching off the early flowers on your Pepperoncini plants can encourage more vegetative growth, leading to a stronger plant and a bigger harvest later in the season. Do this early in the season, before the plant is fully established.

Harvesting frequently is another form of pruning. By picking the peppers regularly, you encourage the plant to produce more. As our first frost approaches in early October, you can remove any remaining small flowers to direct the plant's energy into ripening the existing peppers.

You can expect your first harvest of Pepperoncini from late July through mid-September, about 72 days after transplanting. The peppers are typically harvested when they are yellow-green and about 2-3 inches long, especially if you plan to pickle them. They can also be left on the vine to ripen to a full red color.

To harvest, use pruning shears or a sharp knife to cut the pepper from the plant, leaving a small stem attached. Avoid pulling the peppers, as this can damage the plant. Regular harvesting encourages continuous production throughout the season.

As the first frost approaches in early October, harvest all remaining peppers, even the green ones. Mature green peppers will ripen indoors if stored in a cool, dark place.

Here are a few common problems you might encounter with Pepperoncini in the PNW:

Over-Ripening

• What it looks like: Peppers become overly soft, wrinkled, and may develop dark spots or mold.
• What causes it: Forgetting to harvest at the right time, or leaving peppers on the vine too long. In our mild summers, it's easy to lose track.
• How to fix/prevent it: Check your plants regularly and harvest peppers as they reach the desired size and color. Store harvested peppers properly.

Aphids

• What it looks like: Clusters of tiny soft-bodied insects (green, black, or white) on stems and leaf undersides. Sticky honeydew residue. Curled or distorted new growth.
• What causes it: Rapid-reproducing sap-sucking insects. Populations explode in warm weather. Ant colonies may farm them for honeydew.
• How to fix/prevent it: Strong water spray knocks them off. Encourage ladybugs and lacewings (natural predators). Insecticidal soap for heavy infestations. Neem oil works systemically. Avoid excess nitrogen fertilizer (it attracts them).

Blossom Drop

• What it looks like: Flowers fall off without setting fruit. Small fruit yellows and drops. Plant looks healthy but produces no fruit.
• What causes it: Temperature stress. Peppers and tomatoes don't set fruit well when nights stay above 75°F or days exceed 95°F. Also caused by low humidity, excess nitrogen, or poor pollination.
• How to fix/prevent it: Be patient — fruit set resumes when temperatures moderate. Provide afternoon shade during extreme heat. Keep plants well-watered. Avoid excess nitrogen. Try hand-pollination.

Pacific Northwest Specific Challenges: Because of our dry-summer climate, blossom end rot can be caused by irregular watering. Also, late blight, while more common in tomatoes, can affect peppers as well.

Tomato plants make excellent companions for Pepperoncini, as they share similar growing requirements and can offer mutual support. Basil is another great choice, as it repels many common pests and attracts beneficial insects.

Carrots and onions are also beneficial companions. Carrots loosen the soil, while onions deter pests with their strong scent. Avoid planting Pepperoncini near fennel or brassicas (like cabbage and broccoli). Fennel inhibits the growth of many plants, and brassicas can attract pests that also affect peppers.