When to Plant Daikon in Humboldt County, CA
Daikon is a large, mild Japanese radish that can grow over a foot long. It is excellent for pickling, stir-fries, and as a soil-breaking cover crop.
Humboldt County, California is in USDA Zone 9a. The average last spring frost is February 27 and the first fall frost is November 28, giving you a growing season of approximately 274 days.
At an elevation of 148 feet, Humboldt County receives approximately 22.1 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 87°F, providing good warmth for Daikon during the growing season. Sandy soil warms quickly in spring — great for early planting — but Daikon will need more frequent watering and organic matter to retain nutrients.
Humboldt County Soil Profile
Soil Type
Sandy Loam
Soil pH
6.2-6.8
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 Humboldt County
How your county's soil matches Daikon's growing requirements.
Soil pH
Your soil pH (6.2–6.8) is within Daikon's preferred range (5.8–7.0).
Soil Texture
Sandy soil in Humboldt County warms quickly in spring but drains fast. Daikon will need more frequent watering and regular compost additions to retain nutrients.
Organic Matter
Organic matter is moderate (2.3%). Annual compost additions will help Daikon.
How to Plant Daikon
Fall planting: Sow 8 weeks before your first frost date for a fall harvest.
Succession Planting Daikon
Sow every 5.7 weeks. Last sowing by Sep 19 to harvest before frost.
For a dedicated fall crop, sow by Oct 03.
Plant Water Budget
Monthly Watering Guide for Daikon
Daikon needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Daikon Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 4.8" | 0" | ❄️ Dormant |
| Feb | 4.3" | 5" | 0" | ✅ Rainfall sufficient |
| Mar | 4.3" | 3.3" | 1" | 💧 Light watering |
| Apr | 4.3" | 1.7" | 2.6" | 🚿 Regular watering |
| May | 4.3" | 0.5" | 3.8" | 🚿 Regular watering |
| Jun | 4.3" | 0.1" | 4.2" | 🚿 Regular watering |
| Jul | 4.3" | 0" | 4.3" | 🚿 Regular watering |
| Aug | 4.3" | 0" | 4.3" | 🚿 Regular watering |
| Sep | 4.3" | 0.3" | 4" | 🚿 Regular watering |
| Oct | 4.3" | 0.8" | 3.5" | 🚿 Regular watering |
| Nov | 4.3" | 1.9" | 2.4" | 🚿 Regular watering |
| Dec | — | 3.7" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Feb–Nov in Humboldt County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Daikon 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.
Daikon Planting Timeline — Humboldt County, CA
Daikon Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Direct Sow | February 6 | Feb 6 – Feb 27 |
| Harvest | April 3 | Apr 3 – May 1 |
| Fall Sowing | October 3 | Oct 3 – Oct 17 |
Plant 0.5" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Direct Sow |
| March | — |
| April | Harvest |
| May | Harvest |
| June | — |
| July | — |
| August | — |
| September | — |
| October | Fall Sowing |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1"/week · 1-2 times/week
📅 Days to Maturity
50–70 days
🧪 Soil pH
Needs 5.8–7 · Your soil: ideal
🗺️ USDA Zone
Zone 9a
📆 Growing Season
274 days in Humboldt County
Growing Tips for Daikon in Humboldt County
Direct sow Daikon outdoors after February 27 in Humboldt County when soil has warmed and frost danger has passed.
Sandy soil in Humboldt County dries quickly — mulch Daikon with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.
Common pests for Daikon in this region include cabbage worm and flea beetles. Use row covers early in the season and inspect plants weekly.
Humboldt County receives only 22" of rain annually. Daikon needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.
General growing tips
Direct sow in late summer for fall harvest. Loosen soil deeply before planting. Thin seedlings to 6 inches apart. Harvest before hard freeze as exposed shoulders may crack.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Daikon in Other Locations
Frequently Asked Questions
When should I plant Daikon in Humboldt County, CA?
Humboldt County is in Zone 9a with an average last frost of February 27. Plan your Daikon planting based on this frost date — see the calendar above for exact timing.
What planting zone is Humboldt County, CA?
Humboldt County, California is in USDA Hardiness Zone 9a. The average last spring frost is February 27 and first fall frost is November 28.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Humboldt County gardeners in Zone 9a organize planting dates, track what's growing, and never miss a planting window.
Get Your Free Garden Planner →Free download. Plan your entire garden season in minutes.