Anaheim Pepper in Zone 5B — Mountain West

Anaheim peppers are a fantastic choice for the Mountain West garden. Their mild heat and versatility in the kitchen make them a rewarding crop, and the satisfaction of roasting your own chiles after a summer of tending is hard to beat. Plus, those cool nights we get even in summer help develop a really nice, concentrated flavor.

Our high altitude, intense sun, and short growing season present some challenges, but with careful timing and a little planning, you can absolutely grow Anaheim peppers successfully here. Our 149-day growing season is enough time to bring them to harvest if you start them indoors.

Starting Anaheim pepper seeds indoors is the way to go in our short-season climate. Start your seeds mid-March through early April, roughly 8 weeks before you plan to transplant them outdoors. This gives them a head start before our unpredictable late spring weather hits.

Use seed trays with a good seed-starting mix, and provide consistent warmth (around 75-80°F) using a heat mat if needed. Make sure they get plenty of light – a grow light is essential for strong, healthy seedlings, especially with our intense UV. Water from the bottom to encourage strong root growth and prevent damping-off.

Transplant your Anaheim pepper seedlings outdoors mid-May through mid-June, after the risk of frost has passed. Before planting, harden them off by gradually exposing them to outdoor conditions for about a week. This helps them adjust to the intense sun and cooler nights.

Space your plants 18-24 inches apart in a sunny spot with well-drained soil. Keep an eye on the weather forecast – late frosts or unexpected cold snaps can still occur, so be prepared to cover your plants if necessary.

Anaheim peppers need consistent moisture, but they don't like soggy feet, which is a balance you need to strike in our dry climate. Aim to water deeply about once or twice a week, depending on rainfall and soil drainage. Stick your finger about 2 inches into the soil – if it feels dry, it's time to water.

In our region's low humidity and dry conditions, you’ll generally want to provide about 1-2 inches of water per week, especially during the hottest part of the summer. Water at the base of the plant to avoid wetting the foliage, which can lead to fungal issues, even in our dry air.

Wilting leaves are a sign of underwatering, while yellowing leaves can indicate overwatering. Mulching around your plants with straw or wood chips helps retain moisture and regulate soil temperature, a big plus in our intense sun.

Anaheim pepper plants can get quite tall and laden with fruit, so providing support is a good idea, although not strictly required. Staking is the simplest method.

Install stakes at planting time, placing them a few inches away from the plant. As the plant grows, gently tie the main stem to the stake with soft twine or plant ties. This will prevent the branches from breaking under the weight of the peppers, especially during our occasional summer hail storms.

Pruning Anaheim peppers is fairly straightforward. Pinch off any early flowers that appear before the plant is a foot tall. This encourages the plant to focus on vegetative growth, leading to a stronger plant and higher yields later in the season.

Throughout the season, remove any yellowing or dead leaves. As the first frost approaches in early October, you can pinch off any new flowers to encourage the plant to ripen the existing peppers rather than put energy into new fruit that won't mature.

You can expect your first harvest of Anaheim peppers from early August through mid-September, about 75 days after transplanting. You can harvest them green when they are 6-8 inches long for a milder flavor, or wait until they turn red for more heat.

The peppers should feel firm and have thick walls. Use pruning shears or a sharp knife to cut the peppers from the plant, leaving a short stem attached. Regular harvesting encourages continuous production.

As the first frost approaches in early October, harvest all remaining peppers, even if they are still green. They will ripen indoors if you place them in a paper bag with a ripe apple or banana.

Here are some common problems you might encounter with Anaheim peppers in the Mountain West:

Blossom End Rot

• What it looks like: A sunken, dark brown or black leathery patch on the bottom (blossom end) of the fruit. It often affects the first fruits of the season.
• What causes it: Calcium deficiency caused by inconsistent watering. It's not a disease, but a nutrient uptake problem triggered by our region’s drought/flood cycles.
• How to fix/prevent it: Water consistently! Mulch heavily to maintain even soil moisture. Avoid over-fertilizing with nitrogen, and remove affected fruit.

Sunscald

• What it looks like: White, papery patches on fruit exposed to direct sun. Affected areas may blister and become susceptible to rot.
• What causes it: Intense, direct sunlight on fruit, usually after leaves are removed or lost, suddenly exposing previously shaded fruit. Our high altitude and intense UV make this a real risk.
• How to fix/prevent it: Don't over-prune foliage. Use shade cloth during extreme heat. Maintain healthy foliage to shade fruit naturally. If fruit is already exposed, drape a small piece of row cover over it.

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).

Mountain West Specific Challenges: The combination of intense sun, low humidity, and dry conditions in the Mountain West can stress Anaheim pepper plants, making them more susceptible to blossom end rot and sunscald. Consistent watering and providing adequate shade are key to success.

Companion planting can help your Anaheim peppers thrive. Tomatoes and basil are excellent companions, as they share similar growing requirements and can help deter pests. Carrots and onions are also good choices, as they don't compete for nutrients and can help repel certain insects.

Avoid planting fennel near your peppers, as it can inhibit their growth. Brassicas like cabbage and broccoli also aren't ideal companions, as they can attract pests that may also attack your peppers.