When to Plant Jalapeño Pepper in Boulder, Colorado (80310)
Location
Boulder, Colorado
ZIP Code
80310
USDA Zone
6a
Last Frost
Monday, April 20, 2026
📅 Planting Calendar
Start Seeds Indoors Monday, February 9, 2026
Transplant Outdoors Monday, May 4, 2026
Pro Tip: Start Jalapeño Pepper seeds indoors 10 weeks before your last frost date for best results.
🌿 Plant Details
Scientific Name Capsicum annuum
Days to Maturity 75 days
Mature Height 24-36"
Spread 18"
Type Bush
Fruit Size Small (2-3 inches)
☀️ Growing Requirements
☀️
Sun
Full Sun (6-8 hours)
💧
Water
Moderate
↔️
Spacing
18" apart
🌱
Planting Depth
0.25" deep
Seeds typically germinate in 7-14 days
Other Plants for Boulder
Blackberry Blueberry Raspberry Strawberry Basil Chamomile Chives Cilantro Dill Lavender Lemon Balm Marjoram Mint Oregano Parsley Rosemary Sage Tarragon Thyme Acorn Squash Artichoke Arugula Asparagus Beefsteak Tomato Beet Bell Pepper Bok Choy Broccoli Brussel Sprout Butternut Squash Cabbage Cantaloupe Carrot Cauliflower Cayenne Pepper Celery Cherry Tomato Chili Pepper Collard Green Common Bean Cucumber Eggplant Endive Fennel Garlic Grape Tomato Green Bean Habanero Pepper Head Lettuce Heirloom Tomato Honeydew Melon Kale Kohlrabi Leaf Lettuce Leek Lima Bean Mustard Okra Onion Parsnip Pea Poblano Pepper Pole Pea Potato Pumpkin Radicchio Radish Rhubarb Roma Tomato Rutabaga Serrano Pepper Shallot Snap Pea Snow Pea Spaghetti Squash Spinach Squash Sweet Corn Sweet Potato Swiss Chard Tomato Turnip Watermelon Zucchini
Growing Jalapeño Pepper in Zone 6a
Jalapeño Pepper (Capsicum annuum) is a popular garden vegetable. In Boulder, Colorado, which is in USDA Hardiness Zone 6a, you should start seeds indoors around Monday, February 9, 2026.
Your average last frost date is Monday, April 20, 2026. Plan to transplant your Jalapeño Pepper seedlings outdoors around Monday, May 4, 2026, about 2 weeks after your last frost date.