When to Plant Chard in Jefferson County, CO
Swiss chard is a colorful, heat-tolerant green with large crinkled leaves and vibrant stalks in red, yellow, and white. Both the leaves and stems are edible and nutritious.
Jefferson County, Colorado is in USDA Zone 5b. The average last spring frost is May 14 and the first fall frost is September 26, giving you a growing season of approximately 135 days.
At an elevation of 5,376 feet, Jefferson County receives approximately 22.7 inches of rainfall annually with predominantly loam soil. Summer highs average 84°F, so choose short-season varieties of Chard to ensure they mature before fall.
Jefferson County Soil Profile
Soil Type
Loam
Soil pH
6.8-7.7
Drainage
Well Drained
Monthly Watering Guide for Chard
Chard needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Chard Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.8" | 0" | ❄️ Dormant |
| Feb | — | 1.3" | 0" | ❄️ Dormant |
| Mar | — | 1.9" | 0" | ❄️ Dormant |
| Apr | — | 2.7" | 0" | ❄️ Dormant |
| May | 4.3" | 2.6" | 1.7" | 💧 Light watering |
| Jun | 4.3" | 1.8" | 2.5" | 🚿 Regular watering |
| Jul | 4.3" | 1.9" | 2.4" | 🚿 Regular watering |
| Aug | 4.3" | 2.4" | 1.9" | 💧 Light watering |
| Sep | 4.3" | 1.7" | 2.6" | 🚿 Regular watering |
| Oct | — | 1.8" | 0" | ❄️ Dormant |
| Nov | — | 1.4" | 0" | ❄️ Dormant |
| Dec | — | 1.4" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Sep in Jefferson County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Chard Planting Timeline — Jefferson County, CO
Chard Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | April 9 | Apr 9 – Apr 23 |
| Transplant Outdoors | May 14 | May 14 – May 28 |
| Direct Sow | April 30 | Apr 30 – May 21 |
| Harvest | July 9 | Jul 9 – Aug 27 |
| Fall Sowing | July 18 | Jul 18 – Aug 1 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Start Indoors Direct Sow |
| May | Transplant Outdoors Direct Sow |
| June | — |
| July | Fall Sowing Harvest |
| August | Fall Sowing Harvest |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Partial Shade (3-6 hours)
💧 Water
Moderate — regular watering
📅 Days to Maturity
50–60 days
🧪 Soil pH
Needs 6–7 · Your soil: N/A
🗺️ USDA Zone
Zone 5b
📆 Growing Season
135 days in Jefferson County
Growing Tips for Jefferson County
Direct sow or transplant after last frost. Harvest outer leaves regularly to encourage continuous production. Chard tolerates both heat and light frost.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Chard in Other Locations
Frequently Asked Questions
When should I plant Chard in Jefferson County, CO?
Jefferson County is in Zone 5b with an average last frost of May 14. Plan your Chard planting based on this frost date — see the calendar above for exact timing.
What planting zone is Jefferson County, CO?
Jefferson County, Colorado is in USDA Hardiness Zone 5b. The average last spring frost is May 14 and first fall frost is September 26.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Jefferson County gardeners in Zone 5b organize planting dates, track what's growing, and never miss a planting window.
Get Your Free Garden Planner →Free download. Plan your entire garden season in minutes.