When to Plant Tomatoes in Denver, CO | Garden Planner
Latter Day Homestead
PlannerPricingLog In

When to plant tomatoes in Denver, CO

Use this free 2026 schedule without an account. Compare calculated planting windows, then carry the same frost dates into the planner and adjust them for your garden.

Plan tomatoes in Denver

Compare the planting methods supported for tomatoes. Dates change when you choose a different planning year. Unsupported methods remain unavailable rather than receiving an invented date.

Tomatoes

Start indoors
Mar 9 – Mar 23
Transplant
May 11 – May 18
Direct sow
Not supported by current crop data
Spring harvest estimate
Jul 10 – Aug 11
Fall sow
Not supported by current crop data
Fall harvest estimate
Not supported by current crop data

Soil requirement: 50°F. Maturity: 60-85 days. Best as transplants in short seasons.

Plan the planting space

Seed or planting depth: 0.5 inches. In-row spacing: 18-36 inches. Between rows: 36-60 inches. Light: full sun.

These are crop-level assumptions. Check your variety’s instructions and actual soil conditions. Harvest estimates use 60-85 days from the supported outdoor planting window.

A city calendar cannot describe every elevation, shaded bed or exposed site. Compare the frost-based windows with the crop’s soil requirement, and adjust dates for conditions at your own garden. Colorado State University vegetable planting guide.

Compare all free planner crops for Denver

Where these dates come from

Frost reference: May 4 in spring; Oct 8 in fall. DENVER-STAPLETON, CO US (USW00023062), 1991–2020 NOAA normals, 50% probability at 32°F. The selected representative station is 6.6 miles from the city reference point; it is not a measurement at your garden.

Source retrieved 2026-10-10. Calculation build: 2026-10-10 UTC. Selected planning year: 2026. Autumn buffer: 10 days. Planting and harvest windows use the same crop offsets and maturity ranges as the free planner.

  • 50% probability frost normals are estimates, not frost-safe planting guarantees.
  • These are 1991–2020 normals, not live weather or current soil temperatures.
  • Local elevation, exposure and soil readiness can change planting decisions.
  • Harvest windows use crop maturity ranges and do not guarantee a fall harvest.

Help us learn whether these tools are useful. Optional usage measurement uses a random browser identifier for up to 60 days. We do not collect your address or garden contents for measurement. Browser privacy signals keep measurement off.