When to Plant Kale in Navajo County, AZ
May to-do list for Navajo County, Arizona
May rewards gardeners who work with the weather, not against it. Here's how to stay in step this month in Navajo County, Arizona.
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Transplant kale outside
Plant tomatoes deep — bury the stem up to the first true leaves to grow extra roots. Everything else goes in at the same depth it grew in the tray.
June prep starts now
- Starting indoors: kale
- First harvests: kale
Kale is an exceptionally hardy, nutrient-dense green available in curly, lacinato, and Russian varieties. It tolerates heavy frost and often tastes sweeter after cold exposure.
Navajo County, Arizona is in USDA Zone 7a. The average last spring frost is May 2 and the first fall frost is October 16, giving you a growing season of approximately 167 days.
At an elevation of 5,528 feet, Navajo County receives approximately 15.8 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 94°F, providing good warmth for Kale during the growing season. Sandy soil warms quickly in spring — great for early planting — but Kale will need more frequent watering and organic matter to retain nutrients. With low rainfall, drip irrigation is essential for growing Kale successfully. Mulch heavily to conserve soil moisture.
Navajo County Soil Profile
Soil Type
Sandy Loam
Soil pH
7.3-8.3
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 Navajo County
How your county's soil matches Kale's growing requirements.
Soil pH
Your soil pH (7.3–8.3) is more alkaline than Kale prefers (6.0–7.5). Add sulfur or peat moss to lower pH.
Soil Texture
Sandy soil in Navajo County warms quickly in spring but drains fast. Kale will need more frequent watering and regular compost additions to retain nutrients.
Drainage
Drainage is adequate for Kale.
Organic Matter
Organic matter is low (0.7%). Add 2-3 inches of compost before planting Kale.
How to Plant Kale
Fall planting: Sow 10 weeks before your first frost date for a fall harvest.
Succession Planting Kale
Sow every 5.7 weeks. Last sowing by Aug 07 to harvest before frost.
For a dedicated fall crop, sow by Aug 07.
Plant Water Budget
Water stress score is 10/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Kale
Kale needs approximately 0.8 inches of water per week (3.5" per month). Here's how your county's rainfall compares month by month.
| Month | Kale Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.3" | 0" | ❄️ Dormant |
| Feb | — | 1" | 0" | ❄️ Dormant |
| Mar | — | 0.9" | 0" | ❄️ Dormant |
| Apr | — | 0.6" | 0" | ❄️ Dormant |
| May | 3.5" | 0.3" | 3.2" | 🚿 Regular watering |
| Jun | 3.5" | 0.6" | 2.9" | 🚿 Regular watering |
| Jul | 3.5" | 2.4" | 1.1" | 💧 Light watering |
| Aug | 3.5" | 3.5" | 0" | ✅ Rainfall sufficient |
| Sep | 3.5" | 2" | 1.5" | 💧 Light watering |
| Oct | 3.5" | 1.3" | 2.2" | 🚿 Regular watering |
| Nov | — | 0.8" | 0" | ❄️ Dormant |
| Dec | — | 1.1" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Oct in Navajo County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Kale 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.
Kale Planting Timeline — Navajo County, AZ
Kale Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 28 | Mar 28 – Apr 11 |
| Transplant Outdoors | May 2 | May 2 – May 16 |
| Direct Sow | April 18 | Apr 18 – May 9 |
| Harvest | June 27 | Jun 27 – Aug 22 |
| Fall Sowing | August 7 | Aug 7 – Aug 21 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Start Indoors Direct Sow |
| May | Transplant Outdoors Direct Sow |
| June | Harvest |
| July | Harvest |
| August | Fall Sowing Harvest |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.8"/week · 2-3 times/week
📅 Days to Maturity
50–70 days
🧪 Soil pH
Needs 6–7.5 · Your soil: too_alkaline
🗺️ USDA Zone
Zone 7a
📆 Growing Season
167 days in Navajo County
Growing Tips for Kale in Navajo County
Direct sow Kale outdoors after May 02 in Navajo County when soil has warmed and frost danger has passed.
Sandy soil in Navajo County dries quickly — mulch Kale with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.
Summer highs in Navajo County reach 94°F — grow Kale as a spring or fall crop. Use shade cloth if planting in summer.
Common pests for Kale 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 or transplant in early spring or late summer. Harvest outer leaves first to keep plants productive. Kale overwinters in many climates and can provide greens all year.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Isolate 1/2 mile from other brassicas (broccoli, cabbage, etc.) — they all cross.
Kale in Other Locations
Frequently Asked Questions
When should I plant Kale in Navajo County, AZ?
Navajo County is in Zone 7a with an average last frost of May 2. Plan your Kale planting based on this frost date — see the calendar above for exact timing.
What planting zone is Navajo County, AZ?
Navajo County, Arizona is in USDA Hardiness Zone 7a. The average last spring frost is May 2 and first fall frost is October 16.
Your Navajo County Garden Planner — Free
A 24-page printable planner built for Navajo 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.