Strawberry in Zone 6B — Mountain West

Strawberries are a true taste of summer in the Mountain West, and well worth the effort. There's nothing like a sun-ripened strawberry, bursting with flavor intensified by our intense sun and cool nights. They're incredibly versatile, perfect for snacking, jams, or pies. Plus, the satisfaction of growing your own berries in our challenging climate is hard to beat.

Our high altitude, intense UV, and alkaline soil can make growing anything a bit tricky. But don't let that discourage you. With a little planning and attention, you can absolutely enjoy a bountiful strawberry harvest during our relatively short, 163-day growing season. The key is timing.

Transplant your strawberry starts outdoors from mid-April through early May. This gives them enough time to establish before our brief but intense summer. Make sure to harden off your transplants for about a week before planting. Gradually expose them to the outdoor elements to avoid shocking them.

Space your plants 12-18 inches apart to allow for spreading. Keep an eye on the weather forecast: late spring snow or hard frost is always a possibility in the mountains. Be ready to cover your newly planted strawberries if needed.

Strawberries need consistent moisture, especially when they're fruiting. In our dry Mountain climate, this is crucial. Aim for about 1 inch of water per week, but always check the soil moisture first. Stick your finger about 2 inches deep into the soil. If it feels dry, it's time to water.

Water at the base of the plants to avoid wetting the foliage. Our low humidity is generally a plus, but wet leaves can still lead to fungal problems. Drip irrigation is ideal. Signs of underwatering include wilting leaves and dry, hard berries. Overwatering can lead to root rot, so watch for yellowing leaves and mushy berries.

Mulch heavily around your strawberry plants. This helps retain moisture in our dry air, suppress weeds, and keep the berries clean. Straw, pine needles, or wood chips work well.

Strawberry pruning is pretty minimal, but it's important. Throughout the growing season, remove runners (the long stems that grow out from the main plant) unless you want the plants to spread. Cutting off the runners directs the plant's energy into producing more fruit.

For June-bearing varieties, renovate the beds after harvest. Mow or cut back the foliage to about an inch above the crown. This encourages new growth for next year. As the first frost approaches in early October, don't prune. Leave the foliage in place to insulate the crown over winter.

Get ready for your first strawberry harvest from early July through late August. The berries are ready to pick when they're fully red, fragrant, and have no white shoulders. Pick them in the morning for the best flavor.

Gently twist or cut the berry off the plant, leaving the green cap attached. Harvest regularly to encourage continued production. As the first frost approaches, pick any remaining ripe or nearly-ripe berries. They won't ripen off the vine, but you can use them in jams or smoothies.

Here are some common strawberry problems you might face in the Mountain West:

Gray Mold

• What it looks like: Fuzzy gray mold on berries, especially after wet weather.
• What causes it: A fungal disease that thrives in cool, damp conditions.
• How to fix/prevent it: Improve air circulation by spacing plants properly. Remove infected berries promptly. Water at the base of the plants.

Slugs

• What it looks like: Irregular holes in leaves, especially low-growing plants. Silvery slime trails on leaves and soil. Damage worse at night and in wet weather.
• What causes it: Gastropods that feed at night in moist conditions. Hide under mulch, boards, and debris during the day.
• How to fix/prevent it: Beer traps (shallow dish of beer sunk into soil). Iron phosphate bait (pet-safe). Remove hiding spots. Water in morning so soil surface dries by evening. Copper tape around beds. Diatomaceous earth around plants.

Birds

• What it looks like: Missing or pecked berries.
• What causes it: Birds love strawberries as much as we do!
• How to fix/prevent it: Netting is the most effective solution. You can also try scarecrows or shiny objects, but birds often get used to them.

Strawberry Crown Borer

• What it looks like: Wilting plants, reduced vigor. Small, white grubs inside the crown of the plant.
• What causes it: A beetle larva that tunnels into the crown, damaging the plant.
• How to fix/prevent it: Remove and destroy infested plants. Rotate crops. Beneficial nematodes can help control the larvae in the soil.

Verticillium Wilt

• What it looks like: Lower leaves yellow, wilt, and die, progressing upward. One side of plant may be affected first. Brown streaks in stem cross-section.
• What causes it: Soil-borne fungus that persists for years. Cooler soil temperatures favor it (unlike fusarium). Wide host range.
• How to fix/prevent it: No cure — remove infected plants. Rotate with non-susceptible crops (corn, grains). Solarize soil. Plant resistant varieties (look for 'V' on labels).

Mountain West Specific Challenges: Our moderate-at-altitude heat and low humidity generally help reduce fungal diseases compared to other regions. However, our intense UV radiation can stress plants, making them more susceptible to pests and diseases. Consistent watering and good soil health are key to overcoming these challenges.

Companion planting can really benefit your strawberries. Lettuce and spinach are good companions because they provide ground cover, helping to keep the soil cool and moist. Onions and garlic deter pests with their strong scent. Thyme is also a good pest repellent. Borage attracts beneficial insects that can help pollinate your strawberries.

Avoid planting strawberries near broccoli, cauliflower, peppers, or tomatoes. These plants can compete for nutrients and water, and they may also attract pests that can harm your strawberries. Plus, tomatoes and strawberries are susceptible to Verticillium wilt, so planting them together can increase the risk of disease.