When to Plant Broccoli in Denver, Colorado (80263)
Location
Denver, Colorado
ZIP Code
80263
USDA Zone
6a
Last Frost
Monday, April 20, 2026
📅 Planting Calendar
Direct Sow Outdoors Monday, March 9, 2026
Pro Tip: Broccoli can be directly sown outdoors. Plant 6 weeks before your last frost date.
🌿 Plant Details
Scientific Name Brassica oleracea
Days to Maturity 60 days
Mature Height 18-30"
Spread 18"
Type Head
Fruit Size Medium (4-7 inch head)
☀️ Growing Requirements
☀️
Sun
Full Sun (6 hours)
💧
Water
Regular (1-1.5 inches/week)
↔️
Spacing
18" apart
🌱
Planting Depth
0.5" deep
Seeds typically germinate in 4-7 days
🤝 Good Companions
BeetCeleryOnionPotatoDill
⚠️ Avoid Planting Near
TomatoStrawberryPepper
Other Plants for Denver
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 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 Jalapeño Pepper 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 Broccoli in Zone 6a
Broccoli (Brassica oleracea) is a popular garden vegetable. In Denver, Colorado, which is in USDA Hardiness Zone 6a, you should direct sow seeds around Monday, March 9, 2026.
Your average last frost date is Monday, April 20, 2026. Broccoli grows well when direct sown, as it doesn't transplant well or germinates quickly outdoors.