When to plant Potatoes in Washington County, CO
In Washington County, Potatoes is a spring-only crop. Plant May 17–June 7 once soil hits 50°F.
When to Plant Potatoes in Washington County, CO
Potatoes are a versatile staple crop that produces tubers underground. They come in hundreds of varieties with varying colors, textures, and maturity dates.
Washington County, Colorado is in USDA Zone 5b. The average last spring frost is May 10 and the first fall frost is October 5, giving you a growing season of approximately 148 days.
At an elevation of 6,091 feet, Washington County receives approximately 13 inches of rainfall annually with predominantly loam soil. Summer highs average 85°F, providing good warmth for Potatoes during the growing season. With low rainfall, drip irrigation is essential for growing Potatoes successfully. Mulch heavily to conserve soil moisture.
Washington County Soil Profile
Soil Type
Loam
Soil pH
6.8-8.3
Drainage
Well Drained
How Much Potatoes to Grow
For a family of 4, plant approximately 20 potatoes plants in about 40 sq ft. In Washington County's 148-day season, you'll have plenty of time for a full harvest. Plan your garden layout →
Monthly Watering Guide for Potatoes
Potatoes needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Potatoes Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1" | 0" | ❄️ Dormant |
| Feb | — | 0.7" | 0" | ❄️ Dormant |
| Mar | — | 1" | 0" | ❄️ Dormant |
| Apr | — | 1.4" | 0" | ❄️ Dormant |
| May | 4.3" | 1.5" | 2.8" | 🚿 Regular watering |
| Jun | 4.3" | 1" | 3.3" | 🚿 Regular watering |
| Jul | 4.3" | 1.2" | 3.1" | 🚿 Regular watering |
| Aug | 4.3" | 1.5" | 2.8" | 🚿 Regular watering |
| Sep | 4.3" | 1.1" | 3.2" | 🚿 Regular watering |
| Oct | 4.3" | 1.1" | 3.2" | 🚿 Regular watering |
| Nov | — | 0.9" | 0" | ❄️ Dormant |
| Dec | — | 0.7" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Oct in Washington County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Potatoes Planting Timeline — Washington County, CO
Potatoes Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 15 | Mar 15 – Mar 29 |
| Transplant Outdoors | May 24 | May 24 – Jun 7 |
| Direct Sow | May 17 | May 17 – Jun 7 |
| Harvest | August 2 | Aug 2 – Oct 11 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | — |
| May | Transplant Outdoors Direct Sow |
| June | Transplant Outdoors Direct Sow |
| July | — |
| August | Harvest |
| September | Harvest |
| October | Harvest |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
Moderate — regular watering
📅 Days to Maturity
70–120 days
🧪 Soil pH
Needs 5–6.5 · Your soil: N/A
🗺️ USDA Zone
Zone 5b
📆 Growing Season
148 days in Washington County
Growing Tips for Washington County
Plant seed potatoes (not grocery store potatoes) 4 inches deep in spring. Hill soil around stems as plants grow to prevent greening. Stop watering when plants die back.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Potatoes in Other Locations
Frequently Asked Questions
When should I plant Potatoes in Washington County, CO?
Washington County is in Zone 5b with an average last frost of May 10. Plan your Potatoes planting based on this frost date — see the calendar above for exact timing.
What planting zone is Washington County, CO?
Washington County, Colorado is in USDA Hardiness Zone 5b. The average last spring frost is May 10 and first fall frost is October 5.
When should I plant Potatoes in Washington County, CO?
In Washington County, CO, plant Potatoes after the last frost (around May 10) and before the first frost (around October 5). Best results when soil holds above 50°F.
What growing zone is Washington County, CO for Potatoes?
Washington County sits in USDA Zone 5b. Potatoes grows reliably in zones 3a through 10b, so it's a good fit here.
Can Potatoes grow in Washington County's climate?
Yes — Potatoes grows well in Washington County's temperate climate. Washington County averages a 148-day frost-free season, with last frost around May 10 and first frost around October 5.
Your Washington County Garden Planner — Free
A 22-page printable planner built for Washington County (Zone 5b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.