When to Plant Cauliflower in San Juan County, NM
May in the garden — San Juan County, New Mexico
Welcome to May in Zone 7a. These are the moves that will have the biggest impact on your growing season.
-
Transplant cauliflower outside
Frost risk is low now in San Juan County, New Mexico. If you've been covering beds overnight, you can stop.
To set up a strong June, finish these tasks
- Starting indoors: cauliflower
Cauliflower is a cool-season brassica that produces dense white, purple, or green heads called curds. It is more finicky than broccoli but rewards with a mild, nutty flavor.
San Juan County, New Mexico is in USDA Zone 7a. The average last spring frost is May 12 and the first fall frost is October 6, giving you a growing season of approximately 147 days.
At an elevation of 8,301 feet, San Juan County receives approximately 14.3 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 87°F, providing good warmth for Cauliflower during the growing season. Sandy soil warms quickly in spring — great for early planting — but Cauliflower will need more frequent watering and organic matter to retain nutrients. With low rainfall, drip irrigation is essential for growing Cauliflower successfully. Mulch heavily to conserve soil moisture.
San Juan County Soil Profile
Soil Type
Sandy Loam
Soil pH
7.3-8.5
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 San Juan County
How your county's soil matches Cauliflower's growing requirements.
Soil pH
Your soil pH (7.3–8.5) is more alkaline than Cauliflower prefers (6.0–7.0). Add sulfur or peat moss to lower pH.
Soil Texture
Sandy soil in San Juan County warms quickly in spring but drains fast. Cauliflower will need more frequent watering and regular compost additions to retain nutrients.
Drainage
Cauliflower is a heavy drinker but your soil drains very quickly. Mulch heavily and consider drip irrigation.
Organic Matter
Organic matter is low (0.9%). Add 2-3 inches of compost before planting Cauliflower.
How to Plant Cauliflower
Fall planting: Sow 10 weeks before your first frost date for a fall harvest.
Succession Planting Cauliflower
Sow every 6.3 weeks. Last sowing by Jun 28 to harvest before frost.
For a dedicated fall crop, sow by Jul 28.
Plant Water Budget
Water stress score is 10/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Cauliflower
Cauliflower needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Cauliflower Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.1" | 0" | ❄️ Dormant |
| Feb | — | 0.8" | 0" | ❄️ Dormant |
| Mar | — | 0.8" | 0" | ❄️ Dormant |
| Apr | — | 0.5" | 0" | ❄️ Dormant |
| May | 4.3" | 0.3" | 4" | 🚿 Regular watering |
| Jun | 4.3" | 0.5" | 3.8" | 🚿 Regular watering |
| Jul | 4.3" | 2.5" | 1.8" | 💧 Light watering |
| Aug | 4.3" | 2.6" | 1.7" | 💧 Light watering |
| Sep | 4.3" | 2.2" | 2.1" | 💧 Light watering |
| Oct | 4.3" | 1.3" | 3" | 🚿 Regular watering |
| Nov | — | 0.8" | 0" | ❄️ Dormant |
| Dec | — | 0.9" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Oct in San Juan County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Cauliflower 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.
Cauliflower Planting Timeline — San Juan County, NM
Cauliflower Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | April 7 | Apr 7 – Apr 21 |
| Transplant Outdoors | May 12 | May 12 – May 26 |
| Direct Sow | April 28 | Apr 28 – May 19 |
| Harvest | July 7 | Jul 7 – Sep 8 |
| Fall Sowing | July 28 | Jul 28 – Aug 11 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Start Indoors Direct Sow |
| May | Transplant Outdoors Direct Sow |
| June | — |
| July | Fall Sowing Harvest |
| August | Fall Sowing Harvest |
| September | Harvest |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1"/week · 2-3 times/week
📅 Days to Maturity
55–100 days
🧪 Soil pH
Needs 6–7 · Your soil: too_alkaline
🗺️ USDA Zone
Zone 7a
📆 Growing Season
147 days in San Juan County
Growing Tips for Cauliflower in San Juan County
Direct sow Cauliflower outdoors after May 12 in San Juan County when soil has warmed and frost danger has passed.
Sandy soil in San Juan County dries quickly — mulch Cauliflower with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.
Common pests for Cauliflower in this region include cabbage worm and flea beetles. Use row covers early in the season and inspect plants weekly.
San Juan County receives only 14" of rain annually. Cauliflower needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.
General growing tips
Start seeds indoors 6 weeks before transplanting. Blanch white varieties by tying outer leaves over the head. Provide consistent moisture and avoid temperature extremes.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Cauliflower in Other Locations
Frequently Asked Questions
When should I plant Cauliflower in San Juan County, NM?
San Juan County is in Zone 7a with an average last frost of May 12. Plan your Cauliflower planting based on this frost date — see the calendar above for exact timing.
What planting zone is San Juan County, NM?
San Juan County, New Mexico is in USDA Hardiness Zone 7a. The average last spring frost is May 12 and first fall frost is October 6.
Your San Juan County Garden Planner — Free
A 24-page printable planner built for San Juan County (Zone 7a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.