When to Plant Mustard Greens in Colfax County, NM
May in the garden — Colfax County, New Mexico
Welcome to May in Zone 6a. These are the moves that will have the biggest impact on your growing season.
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Move mustard greens from tray to bed
Water the tray well an hour before you transplant. Roots slide out cleanly and settle in faster.
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Seed mustard greens outdoors
Thin ruthlessly once seedlings are up. Crowded roots mean smaller crops from every plant.
Get ahead of June
- Starting indoors: mustard greens
- 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.
Colfax County, New Mexico is in USDA Zone 6a. The average last spring frost is May 15 and the first fall frost is September 26, giving you a growing season of approximately 134 days.
At an elevation of 5,131 feet, Colfax County receives approximately 15.5 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 84°F, so choose short-season varieties of Mustard Greens to ensure they mature before fall. Sandy soil warms quickly in spring — great for early planting — but Mustard Greens will need more frequent watering and organic matter to retain nutrients. With low rainfall, drip irrigation is essential for growing Mustard Greens successfully. Mulch heavily to conserve soil moisture.
Colfax County Soil Profile
Soil Type
Sandy Loam
Soil pH
7.1-8.1
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 Colfax County
How your county's soil matches Mustard Greens's growing requirements.
Soil pH
Your soil pH (7.1–8.1) is more alkaline than Mustard Greens prefers (6.0–7.0). Add sulfur or peat moss to lower pH.
Soil Texture
Sandy soil in Colfax County warms quickly in spring but drains fast. Mustard Greens will need more frequent watering and regular compost additions to retain nutrients.
Drainage
Drainage is adequate for Mustard Greens.
Organic Matter
Organic matter is low (0.9%). Add 2-3 inches of compost before planting 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 Aug 07 to harvest before frost.
For a dedicated fall crop, sow by Jul 18.
Plant Water Budget
Water stress score is 10/10 — consider drought-tolerant varieties and mulching
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 | — | 1.1" | 0" | ❄️ Dormant |
| Feb | — | 0.8" | 0" | ❄️ Dormant |
| Mar | — | 0.9" | 0" | ❄️ Dormant |
| Apr | — | 0.5" | 0" | ❄️ Dormant |
| May | 3" | 0.4" | 2.6" | 🚿 Regular watering |
| Jun | 3" | 0.5" | 2.5" | 🚿 Regular watering |
| Jul | 3" | 3" | 0" | ✅ Rainfall sufficient |
| Aug | 3" | 2.9" | 0.1" | 💧 Light watering |
| Sep | 3" | 2" | 1" | 💧 Light watering |
| Oct | — | 1.3" | 0" | ❄️ Dormant |
| Nov | — | 1" | 0" | ❄️ Dormant |
| Dec | — | 1" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Sep in Colfax 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 — Colfax County, NM
Mustard Greens Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | April 10 | Apr 10 – Apr 24 |
| Transplant Outdoors | May 15 | May 15 – May 29 |
| Direct Sow | May 1 | May 1 – May 22 |
| Harvest | June 19 | Jun 19 – Aug 21 |
| Fall Sowing | July 18 | Jul 18 – Aug 1 |
Plant 0.5" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Start Indoors |
| May | Transplant Outdoors Direct Sow |
| June | Harvest |
| July | Fall Sowing Harvest |
| August | Fall Sowing Harvest |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Partial Shade (3-6 hours)
💧 Water
0.7"/week · 1-2 times/week
📅 Days to Maturity
30–50 days
🧪 Soil pH
Needs 6–7 · Your soil: too_alkaline
🗺️ USDA Zone
Zone 6a
📆 Growing Season
134 days in Colfax County
Growing Tips for Mustard Greens in Colfax County
Direct sow Mustard Greens outdoors after May 15 in Colfax County when soil has warmed and frost danger has passed.
Sandy soil in Colfax County dries quickly — mulch Mustard Greens with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.
Your generous 134.0-day season in Colfax 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 Colfax County, NM?
Colfax County is in Zone 6a with an average last frost of May 15. Plan your Mustard Greens planting based on this frost date — see the calendar above for exact timing.
What planting zone is Colfax County, NM?
Colfax County, New Mexico is in USDA Hardiness Zone 6a. The average last spring frost is May 15 and first fall frost is September 26.
Your Colfax County Garden Planner — Free
A 24-page printable planner built for Colfax County (Zone 6a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.