When to Plant Zucchini in Park County, CO
May to-do list for Park County, Colorado
A quick May briefing for Park County, Colorado gardeners — what's urgent, what's next, and what can wait.
June prep starts now
- Transplants going out: zucchini
- Direct-sowing: zucchini
Zucchini is an incredibly prolific summer squash that can produce an abundance of fruit from just a few plants. It is versatile in the kitchen from grilling to baking.
Park County, Colorado is in USDA Zone 5b. The average last spring frost is June 16 and the first fall frost is September 4, giving you a growing season of approximately 80 days.
At an elevation of 7,567 feet, Park County receives approximately 23.3 inches of rainfall annually with predominantly loam soil. Summer highs average 83°F, so choose short-season varieties of Zucchini to ensure they mature before fall.
Park County Soil Profile
Soil Type
Loam
Soil pH
6.2-7.6
Drainage
Well Drained
Plant Planting Risk Windows
Percentages indicate frost risk at transplant. The 70% safe window means there is a 30% chance of frost after transplant — suitable for cold-hardy crops or gardeners with frost protection. The 90% safe window is best for tender plants.
Soil Compatibility in Park County
How your county's soil matches Zucchini's growing requirements.
Soil pH
Your soil pH (6.2–7.6) overlaps with Zucchini's range (6.0–7.5), though not a perfect match.
Soil Texture
The loam soil in Park County is excellent for Zucchini — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Zucchini.
Organic Matter
Organic matter is moderate (2.6%). Annual compost additions will help Zucchini.
How to Plant Zucchini
How Much Zucchini to Grow
For a family of 4, plant approximately 4 zucchini plants in about 35 sq ft. In Park County's 80-day season, you'll have plenty of time for a full harvest. Plan your garden layout →
Plant Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Zucchini
Zucchini needs approximately 1.2 inches of water per week (5.2" per month). Here's how your county's rainfall compares month by month.
| Month | Zucchini Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.5" | 0" | ❄️ Dormant |
| Feb | — | 1.2" | 0" | ❄️ Dormant |
| Mar | — | 1.9" | 0" | ❄️ Dormant |
| Apr | — | 2.2" | 0" | ❄️ Dormant |
| May | — | 3.1" | 0" | ❄️ Dormant |
| Jun | 5.2" | 1.8" | 3.4" | 🚿 Regular watering |
| Jul | 5.2" | 2.2" | 3" | 🚿 Regular watering |
| Aug | 5.2" | 2.7" | 2.5" | 💧 Light watering |
| Sep | 5.2" | 1.8" | 3.4" | 🚿 Regular watering |
| Oct | — | 1.8" | 0" | ❄️ Dormant |
| Nov | — | 1.7" | 0" | ❄️ Dormant |
| Dec | — | 1.4" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Jun–Sep in Park County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Zucchini Heat Requirements (GDD)
What are Growing Degree Days (GDD)?
Growing Degree Days measure the total warmth your plants receive during the growing season. Think of it as a "heat bank" — every day above 50°F deposits warmth that helps your plants grow.
Each plant needs a certain amount of accumulated heat to mature. If your county provides more GDD than the plant needs, it's a great fit. If it's close, you may want to choose faster-maturing varieties or start seeds indoors to get a head start.
Zucchini Planting Timeline — Park County, CO
Zucchini Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | May 12 | May 12 – May 26 |
| Transplant Outdoors | June 30 | Jun 30 – Jul 14 |
| Direct Sow | June 23 | Jun 23 – Jul 14 |
| Harvest | August 18 | Aug 18 – Oct 13 |
Plant 1" deep · 30" apart · Rows 42" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | — |
| May | Start Indoors |
| June | Transplant Outdoors Direct Sow |
| July | Transplant Outdoors Direct Sow |
| August | Harvest |
| September | Harvest |
| October | Harvest |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1.2"/week · 1-2 times/week
📅 Days to Maturity
45–60 days
🧪 Soil pH
Needs 6–7.5 · Your soil: acceptable
🗺️ USDA Zone
Zone 5b
📆 Growing Season
80 days in Park County
Growing Tips for Zucchini in Park County
Direct sow Zucchini outdoors after June 16 in Park County when soil has warmed and frost danger has passed.
Common pests for Zucchini in this region include squash vine borer and cucumber beetles. Use row covers early in the season and inspect plants weekly.
Park County receives only 23" of rain annually. Zucchini needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.
General growing tips
Direct sow after last frost. Harvest when fruits are 6-8 inches long for best flavor and texture. Check plants daily in summer as fruits can double in size overnight.
Recommended Zucchini Varieties for Park County
Quick-producing varieties for shorter seasons
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Zucchini in Other Locations
Frequently Asked Questions
When should I plant Zucchini in Park County, CO?
Park County is in Zone 5b with an average last frost of June 16. Plan your Zucchini planting based on this frost date — see the calendar above for exact timing.
What planting zone is Park County, CO?
Park County, Colorado is in USDA Hardiness Zone 5b. The average last spring frost is June 16 and first fall frost is September 4.
Your Park County Garden Planner — Free
A 24-page printable planner built for Park 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.