Grow It in ColoradoPlanting Calendar
Colorado's elevation varies enormously, so planting time depends far more on your location than on the calendar. Use the ranges below as starting points and confirm with local frost data from CSU Extension and your county office.
If you start seeds indoors, see Starting Seeds Indoors for timing based on a mid-May last frost around Colorado Springs, Fountain and El Paso County.
Cool-season vs. warm-season crops
Cool-season
Tolerate light frost; plant in early spring and again for fall: peas, spinach, lettuce, radishes, kale, chard, carrots, beets, onions, potatoes, broccoli, cabbage.
Warm-season
Damaged by frost; plant after the last frost once soil warms: tomatoes, peppers, eggplant, beans, corn, squash, cucumbers, melons, basil.
General timing by region
These are broad, approximate ranges. A single cold night can occur well after average last-frost dates, so watch the forecast and be ready to cover plants.
| Region | Cool-season crops (direct seed / transplant) | Warm-season crops (after frost danger) | Notes |
|---|---|---|---|
| Front Range urban corridor (Denver, Colorado Springs, Fort Collins) | Roughly late March to April | Typically mid-to-late May, often later at higher sites | Average last spring frost roughly early to mid May; first fall frost roughly late September to early October. Varies by neighborhood and elevation. |
| Mountains & high valleys | Roughly May to June | June, if at all; choose very short-season crops | Frost possible almost any month at high elevation; season may be under 100 days or much less. |
| Western Slope lower valleys (Grand Junction, Palisade) | Roughly March to April | Roughly late April to mid May | Longer, warmer season; known for peaches and other fruit. |
| Eastern Plains | Roughly late March to April | Roughly mid-to-late May | Hot summers, strong wind and hail; windbreaks are valuable. |
Tips
- Use a soil thermometer: many warm-season seeds germinate poorly in cold soil.
- Harden off transplants before setting them out; see Starting Seeds Indoors for how and when.
- Plant a second round of cool-season crops in late summer for fall harvest.
- For your exact location, see CSU Extension's vegetable planting guide and frost-date resources, and ask the El Paso County Extension office in the Colorado Springs area.