When to Plant Squash (Summer) in Fairfax County, VA
Top priorities for Fairfax County, Virginia gardeners in May
A quick May briefing for Fairfax County, Virginia gardeners — what's urgent, what's next, and what can wait.
-
Sow squash (summer) in trays indoors
Starting these indoors now means sturdy transplants ready the moment your soil warms up.
A few tasks this May that'll pay off in June
- First harvests: squash (summer)
Summer squash includes zucchini, yellow crookneck, and pattypan varieties that are harvested young and tender. They are prolific producers in warm weather.
Fairfax County, Virginia is in USDA Zone 7b. The average last spring frost is April 6 and the first fall frost is November 3, giving you a growing season of approximately 211 days.
At an elevation of 548 feet, Fairfax County receives approximately 53 inches of rainfall annually with predominantly silt loam soil. Summer highs average 93°F, providing good warmth for Squash (Summer) during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Squash (Summer) root diseases.
Fairfax County Soil Profile
Soil Type
Silt Loam
Soil pH
5.4-6.5
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 Fairfax County
How your county's soil matches Squash (Summer)'s growing requirements.
Soil pH
Your soil pH (5.4–6.5) is more acidic than Squash (Summer) prefers (6.0–7.5). Add garden lime to raise pH.
Soil Texture
The silt loam soil in Fairfax County is excellent for Squash (Summer) — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.8%). Annual compost additions will help Squash (Summer).
How to Plant Squash (Summer)
Succession Planting Squash (Summer)
Sow every 5.1 weeks. Last sowing by Aug 30 to harvest before frost.
Plant Water Budget
Monthly Watering Guide for Squash (Summer)
Squash (Summer) needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Squash (Summer) Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 4.1" | 0" | ❄️ Dormant |
| Feb | — | 4.6" | 0" | ❄️ Dormant |
| Mar | — | 5.5" | 0" | ❄️ Dormant |
| Apr | 4.3" | 4.1" | 0.2" | 💧 Light watering |
| May | 4.3" | 3.8" | 0.5" | 💧 Light watering |
| Jun | 4.3" | 5" | 0" | ✅ Rainfall sufficient |
| Jul | 4.3" | 5.9" | 0" | ✅ Rainfall sufficient |
| Aug | 4.3" | 4.1" | 0.2" | 💧 Light watering |
| Sep | 4.3" | 3.8" | 0.5" | 💧 Light watering |
| Oct | 4.3" | 3.3" | 1" | 💧 Light watering |
| Nov | 4.3" | 4.4" | 0" | ✅ Rainfall sufficient |
| Dec | — | 4.4" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Nov in Fairfax County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Squash (Summer) 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.
Squash (Summer) Planting Timeline — Fairfax County, VA
Squash (Summer) Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 9 | Mar 9 – Mar 23 |
| Transplant Outdoors | April 20 | Apr 20 – May 4 |
| Direct Sow | April 13 | Apr 13 – May 4 |
| Harvest | June 8 | Jun 8 – Aug 10 |
Plant 1" deep · 30" apart · Rows 42" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Transplant Outdoors Direct Sow |
| May | Transplant Outdoors Direct Sow |
| June | Harvest |
| July | Harvest |
| August | Harvest |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1"/week · Natural rainfall sufficient
📅 Days to Maturity
45–65 days
🧪 Soil pH
Needs 6–7.5 · Your soil: too_acidic
🗺️ USDA Zone
Zone 7b
📆 Growing Season
211 days in Fairfax County
Growing Tips for Squash (Summer) in Fairfax County
Direct sow Squash (Summer) outdoors after April 06 in Fairfax County when soil has warmed and frost danger has passed.
Your generous 211.0-day season in Fairfax County allows multiple plantings of Squash (Summer). Sow every 22.0 days for continuous harvest.
Common pests for Squash (Summer) in this region include squash vine borer and cucumber beetles. Use row covers early in the season and inspect plants weekly.
General growing tips
Direct sow after last frost on mounds. Harvest frequently when fruits are 6-8 inches for best texture. Check plants daily as they grow rapidly in summer heat.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Squash (Summer) in Other Locations
Frequently Asked Questions
When should I plant Squash (Summer) in Fairfax County, VA?
Fairfax County is in Zone 7b with an average last frost of April 6. Plan your Squash (Summer) planting based on this frost date — see the calendar above for exact timing.
What planting zone is Fairfax County, VA?
Fairfax County, Virginia is in USDA Hardiness Zone 7b. The average last spring frost is April 6 and first fall frost is November 3.
Your Fairfax County Garden Planner — Free
A 24-page printable planner built for Fairfax County (Zone 7b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.