When to Plant Mustard Greens in Millard County, UT
This month in Millard County, Utah
A quick May briefing for Millard County, Utah gardeners — what's urgent, what's next, and what can wait.
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Time to transplant mustard greens
Your last frost (May 16) has passed. These warm-season crops can handle outdoor soil now.
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Scatter mustard greens into prepared beds
Your soil is 38°F — warm enough for these to germinate without babying.
A few tasks this May that'll pay off in 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.
Millard County, Utah is in USDA Zone 6a. The average last spring frost is May 16 and the first fall frost is September 30, giving you a growing season of approximately 137 days.
At an elevation of 6,525 feet, Millard County receives approximately 24 inches of rainfall annually with predominantly loam soil. Summer highs average 84°F, so choose short-season varieties of Mustard Greens to ensure they mature before fall.
Millard County Soil Profile
Soil Type
Loam
Soil pH
6.5-8
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 Millard County
How your county's soil matches Mustard Greens's growing requirements.
Soil pH
Your soil pH (6.5–8.0) is more alkaline than Mustard Greens prefers (6.0–7.0). Add sulfur or peat moss to lower pH.
Soil Texture
The loam soil in Millard County is excellent for Mustard Greens — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.3%). 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 Aug 11 to harvest before frost.
For a dedicated fall crop, sow by Jul 22.
Plant Water Budget
Water stress score is 8/10 — 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 | — | 1.8" | 0" | ❄️ Dormant |
| Feb | — | 1.5" | 0" | ❄️ Dormant |
| Mar | — | 2" | 0" | ❄️ Dormant |
| Apr | — | 2.7" | 0" | ❄️ Dormant |
| May | 3" | 2.7" | 0.3" | 💧 Light watering |
| Jun | 3" | 1.7" | 1.3" | 💧 Light watering |
| Jul | 3" | 2.1" | 0.9" | 💧 Light watering |
| Aug | 3" | 2.2" | 0.8" | 💧 Light watering |
| Sep | 3" | 2" | 1" | 💧 Light watering |
| Oct | — | 2.2" | 0" | ❄️ Dormant |
| Nov | — | 1.6" | 0" | ❄️ Dormant |
| Dec | — | 1.5" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Sep in Millard 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 — Millard County, UT
Mustard Greens Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | April 11 | Apr 11 – Apr 25 |
| Transplant Outdoors | May 16 | May 16 – May 30 |
| Direct Sow | May 2 | May 2 – May 23 |
| Harvest | June 20 | Jun 20 – Aug 22 |
| Fall Sowing | July 22 | Jul 22 – Aug 5 |
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 · Natural rainfall sufficient
📅 Days to Maturity
30–50 days
🧪 Soil pH
Needs 6–7 · Your soil: too_alkaline
🗺️ USDA Zone
Zone 6a
📆 Growing Season
137 days in Millard County
Growing Tips for Mustard Greens in Millard County
Direct sow Mustard Greens outdoors after May 16 in Millard County when soil has warmed and frost danger has passed.
Your generous 137.0-day season in Millard 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 Millard County, UT?
Millard County is in Zone 6a with an average last frost of May 16. Plan your Mustard Greens planting based on this frost date — see the calendar above for exact timing.
What planting zone is Millard County, UT?
Millard County, Utah is in USDA Hardiness Zone 6a. The average last spring frost is May 16 and first fall frost is September 30.
Your Millard County Garden Planner — Free
A 24-page printable planner built for Millard 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.