When to Plant Napa Cabbage in Placer County, CA
Placer County, California gardeners: here's your May plan
If you only do a handful of things in the garden this May, make it these. They're sequenced around your zone's frost timing.
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Start napa cabbage indoors
These need a head start before your last frost (April 22). Sow into cells now so you're ready to transplant in a few weeks.
June prep starts now
- First harvests: napa cabbage
Napa cabbage forms tall, barrel-shaped heads with tender, crinkled leaves and a mild, slightly sweet flavor. It is the primary cabbage used for kimchi.
Placer County, California is in USDA Zone 9b. The average last spring frost is April 22 and the first fall frost is November 9, giving you a growing season of approximately 201 days.
At an elevation of 651 feet, Placer County receives approximately 25.3 inches of rainfall annually with predominantly loam soil. Summer highs average 85°F, providing good warmth for Napa Cabbage during the growing season.
Placer County Soil Profile
Soil Type
Loam
Soil pH
6.6-7.2
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 Placer County
How your county's soil matches Napa Cabbage's growing requirements.
Soil pH
Your soil pH (6.6–7.2) is within Napa Cabbage's preferred range (6.0–7.5).
Soil Texture
The loam soil in Placer County is excellent for Napa Cabbage — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Napa Cabbage is a heavy drinker but your soil drains very quickly. Mulch heavily and consider drip irrigation.
Organic Matter
Organic matter is moderate (3.1%). Annual compost additions will help Napa Cabbage.
How to Plant Napa Cabbage
Fall planting: Sow 8 weeks before your first frost date for a fall harvest.
Succession Planting Napa Cabbage
Sow every 6.3 weeks. Last sowing by Aug 26 to harvest before frost.
For a dedicated fall crop, sow by Sep 14.
Plant Water Budget
Water stress score is 8/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Napa Cabbage
Napa Cabbage needs approximately 1.5 inches of water per week (6.5" per month). Here's how your county's rainfall compares month by month.
| Month | Napa Cabbage Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 5.2" | 0" | ❄️ Dormant |
| Feb | — | 5.3" | 0" | ❄️ Dormant |
| Mar | — | 4.2" | 0" | ❄️ Dormant |
| Apr | 6.5" | 1.7" | 4.8" | 🚿 Regular watering |
| May | 6.5" | 0.7" | 5.8" | 🚿 Regular watering |
| Jun | 6.5" | 0.1" | 6.4" | 🚿 Regular watering |
| Jul | 6.5" | 0" | 6.5" | 🚿 Regular watering |
| Aug | 6.5" | 0" | 6.5" | 🚿 Regular watering |
| Sep | 6.5" | 0.2" | 6.3" | 🚿 Regular watering |
| Oct | 6.5" | 1.1" | 5.4" | 🚿 Regular watering |
| Nov | 6.5" | 2.4" | 4.1" | 🚿 Regular watering |
| Dec | — | 4.4" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Nov in Placer County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Napa Cabbage 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.
Napa Cabbage Planting Timeline — Placer County, CA
Napa Cabbage Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 25 | Mar 25 – Apr 8 |
| Transplant Outdoors | April 22 | Apr 22 – May 6 |
| Direct Sow | April 1 | Apr 1 – Apr 22 |
| Harvest | June 17 | Jun 17 – Jul 22 |
| Fall Sowing | September 14 | Sep 14 – Sep 28 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Start Indoors Transplant Outdoors Direct Sow |
| May | Transplant Outdoors |
| June | Harvest |
| July | Harvest |
| August | — |
| September | Fall Sowing |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Partial Shade (3-6 hours)
💧 Water
1.5"/week · 2-3 times/week
📅 Days to Maturity
55–75 days
🧪 Soil pH
Needs 6–7.5 · Your soil: ideal
🗺️ USDA Zone
Zone 9b
📆 Growing Season
201 days in Placer County
Growing Tips for Napa Cabbage in Placer County
Direct sow Napa Cabbage outdoors after April 22 in Placer County when soil has warmed and frost danger has passed.
Common pests for Napa Cabbage in this region include cabbage worm and flea beetles. Use row covers early in the season and inspect plants weekly.
General growing tips
Best grown as a fall crop. Direct sow in late summer, 60-70 days before first frost. Keep soil evenly moist. Bolt-resistant varieties are available for spring planting.
Companion Planting
Good Companions
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Check more plant combinations with our Companion Planting Checker →
Napa Cabbage in Other Locations
Frequently Asked Questions
When should I plant Napa Cabbage in Placer County, CA?
Placer County is in Zone 9b with an average last frost of April 22. Plan your Napa Cabbage planting based on this frost date — see the calendar above for exact timing.
What planting zone is Placer County, CA?
Placer County, California is in USDA Hardiness Zone 9b. The average last spring frost is April 22 and first fall frost is November 9.
Your Placer County Garden Planner — Free
A 24-page printable planner built for Placer County (Zone 9b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.