When to Plant Kale in Clark County, ID
May in the garden — Clark County, Idaho
Your Clark County, Idaho garden is entering a new phase. Here's what's on the schedule for May and why each task matters now.
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Sow kale where they'll grow
These tolerate cool soil, so you're not gambling by sowing now.
Get ahead of June
- Transplants going out: 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.
Clark County, Idaho is in USDA Zone 5b. The average last spring frost is June 7 and the first fall frost is September 10, giving you a growing season of approximately 95 days.
At an elevation of 7,493 feet, Clark County receives approximately 21.9 inches of rainfall annually with predominantly loam soil. Summer highs average 82°F, so choose short-season varieties of Kale to ensure they mature before fall.
Clark County Soil Profile
Soil Type
Loam
Soil pH
6.8-7.8
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 Clark County
How your county's soil matches Kale's growing requirements.
Soil pH
Your soil pH (6.8–7.8) overlaps with Kale's range (6.0–7.5), though not a perfect match.
Soil Texture
The loam soil in Clark County is excellent for Kale — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.4%). Annual compost additions will help 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 Jul 02 to harvest before frost.
For a dedicated fall crop, sow by Jul 02.
Plant Water Budget
Water stress score is 6/10 — 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 | — | 1.7" | 0" | ❄️ Dormant |
| Feb | — | 1.4" | 0" | ❄️ Dormant |
| Mar | — | 1.8" | 0" | ❄️ Dormant |
| Apr | — | 2.5" | 0" | ❄️ Dormant |
| May | — | 2.5" | 0" | ❄️ Dormant |
| Jun | 3.5" | 1.5" | 2" | 🚿 Regular watering |
| Jul | 3.5" | 1.7" | 1.8" | 🚿 Regular watering |
| Aug | 3.5" | 2.2" | 1.3" | 💧 Light watering |
| Sep | 3.5" | 1.7" | 1.8" | 🚿 Regular watering |
| Oct | — | 1.8" | 0" | ❄️ Dormant |
| Nov | — | 1.6" | 0" | ❄️ Dormant |
| Dec | — | 1.3" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Jun–Sep in Clark 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 — Clark County, ID
Kale Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | May 3 | May 3 – May 17 |
| Transplant Outdoors | June 7 | Jun 7 – Jun 21 |
| Direct Sow | May 24 | May 24 – Jun 14 |
| Harvest | August 2 | Aug 2 – Sep 27 |
| Fall Sowing | July 2 | Jul 2 – Jul 16 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | — |
| May | Start Indoors Direct Sow |
| June | Transplant Outdoors Direct Sow |
| July | Fall Sowing |
| August | Harvest |
| September | Harvest |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.8"/week · Natural rainfall sufficient
📅 Days to Maturity
50–70 days
🧪 Soil pH
Needs 6–7.5 · Your soil: acceptable
🗺️ USDA Zone
Zone 5b
📆 Growing Season
95 days in Clark County
Growing Tips for Kale in Clark County
Direct sow Kale outdoors after June 07 in Clark County when soil has warmed and frost danger has passed.
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.
Recommended Kale Varieties for Clark County
Cold-hardy kale that improves in flavor after frost
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 Clark County, ID?
Clark County is in Zone 5b with an average last frost of June 7. Plan your Kale planting based on this frost date — see the calendar above for exact timing.
What planting zone is Clark County, ID?
Clark County, Idaho is in USDA Hardiness Zone 5b. The average last spring frost is June 7 and first fall frost is September 10.
Your Clark County Garden Planner — Free
A 24-page printable planner built for Clark County (Zone 5b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.