When to Plant Mustard Greens in Fairfax County, VA
May in Fairfax County, Virginia — your action list
Here's what deserves your attention in Fairfax County, Virginia this month. Everything below is tailored to Zone 7b and timed around your local frost dates.
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Start mustard greens under lights
These need a head start before your last frost (April 6). Sow into cells now so you're ready to transplant in a few weeks.
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Harvest mustard greens as they ripen
Taste as you pick. The first ripe produce is the best feedback loop you'll get all season.
June prep starts now
- First harvests: mustard greens
Mustard greens are fast-growing brassicas with a spicy, peppery kick. They come in green, red, and purple varieties and are excellent cooked or in salads.
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 Mustard Greens during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Mustard Greens 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 Mustard Greens's growing requirements.
Soil pH
Your soil pH (5.4–6.5) is more acidic than Mustard Greens prefers (6.0–7.0). Add garden lime to raise pH.
Soil Texture
The silt loam soil in Fairfax County is excellent for Mustard Greens — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.8%). Annual compost additions will help Mustard Greens.
How to Plant Mustard Greens
Fall planting: Sow 10 weeks before your first frost date for a fall harvest.
Succession Planting Mustard Greens
Sow every 3.4 weeks. Last sowing by Sep 14 to harvest before frost.
For a dedicated fall crop, sow by Aug 25.
Plant Water Budget
Monthly Watering Guide for Mustard Greens
Mustard Greens needs approximately 0.7 inches of water per week (3" per month). Here's how your county's rainfall compares month by month.
| Month | Mustard Greens Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 4.1" | 0" | ❄️ Dormant |
| Feb | — | 4.6" | 0" | ❄️ Dormant |
| Mar | — | 5.5" | 0" | ❄️ Dormant |
| Apr | 3" | 4.1" | 0" | ✅ Rainfall sufficient |
| May | 3" | 3.8" | 0" | ✅ Rainfall sufficient |
| Jun | 3" | 5" | 0" | ✅ Rainfall sufficient |
| Jul | 3" | 5.9" | 0" | ✅ Rainfall sufficient |
| Aug | 3" | 4.1" | 0" | ✅ Rainfall sufficient |
| Sep | 3" | 3.8" | 0" | ✅ Rainfall sufficient |
| Oct | 3" | 3.3" | 0" | ✅ Rainfall sufficient |
| Nov | 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.
Mustard Greens 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.
Mustard Greens Planting Timeline — Fairfax County, VA
Mustard Greens Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 2 | Mar 2 – Mar 16 |
| Transplant Outdoors | April 6 | Apr 6 – Apr 20 |
| Direct Sow | March 23 | Mar 23 – Apr 13 |
| Harvest | May 11 | May 11 – Jul 13 |
| Fall Sowing | August 25 | Aug 25 – Sep 8 |
Plant 0.5" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors Direct Sow |
| April | Transplant Outdoors Direct Sow |
| May | Harvest |
| June | Harvest |
| July | Harvest |
| August | Fall Sowing |
| September | Fall Sowing |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Partial Shade (3-6 hours)
💧 Water
0.7"/week · Natural rainfall sufficient
📅 Days to Maturity
30–50 days
🧪 Soil pH
Needs 6–7 · Your soil: too_acidic
🗺️ USDA Zone
Zone 7b
📆 Growing Season
211 days in Fairfax County
Growing Tips for Mustard Greens in Fairfax County
Direct sow Mustard Greens 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 Mustard Greens. Sow every 15.0 days for continuous harvest.
Common pests for Mustard Greens in this region include cabbage worm and flea beetles. Use row covers early in the season and inspect plants weekly.
General growing tips
Direct sow in early spring or fall. Harvest young leaves for milder flavor. Plants bolt quickly in heat so grow as a cool-season crop or provide shade.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Mustard Greens in Other Locations
Frequently Asked Questions
When should I plant Mustard Greens in Fairfax County, VA?
Fairfax County is in Zone 7b with an average last frost of April 6. Plan your Mustard Greens 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.