When to Plant Daikon in Columbia County, OR
May in Columbia County, Oregon — your action list
May is a pivotal month for Columbia County, Oregon gardens. Focus on these tasks first and you'll set up the rest of the season for success.
-
It's harvest week for daikon
Morning harvests are best — cooler temperatures mean crisper produce and longer fridge life.
Before June arrives, get these ready
- First harvests: daikon
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.
Columbia County, Oregon is in USDA Zone 8b. The average last spring frost is April 14 and the first fall frost is October 29, giving you a growing season of approximately 198 days.
At an elevation of 396 feet, Columbia County receives approximately 46.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85°F, providing good warmth for Daikon during the growing season.
Columbia County Soil Profile
Soil Type
Silt Loam
Soil pH
5.5-6.6
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 Columbia County
How your county's soil matches Daikon's growing requirements.
Soil pH
Your soil pH (5.5–6.6) overlaps with Daikon's range (5.8–7.0), though not a perfect match.
Soil Texture
The silt loam soil in Columbia County is excellent for Daikon — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (4.6%) — Daikon will thrive.
How to Plant Daikon
Fall planting: Sow 10 weeks before your first frost date for a fall harvest.
Succession Planting Daikon
Sow every 5.7 weeks. Last sowing by Aug 20 to harvest before frost.
For a dedicated fall crop, sow by Aug 20.
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 | — | 6.5" | 0" | ❄️ Dormant |
| Feb | — | 4.8" | 0" | ❄️ Dormant |
| Mar | — | 4.9" | 0" | ❄️ Dormant |
| Apr | 4.3" | 3.2" | 1.1" | 💧 Light watering |
| May | 4.3" | 2.9" | 1.4" | 💧 Light watering |
| Jun | 4.3" | 1.7" | 2.6" | 🚿 Regular watering |
| Jul | 4.3" | 0.7" | 3.6" | 🚿 Regular watering |
| Aug | 4.3" | 0.8" | 3.5" | 🚿 Regular watering |
| Sep | 4.3" | 1.9" | 2.4" | 🚿 Regular watering |
| Oct | 4.3" | 3.9" | 0.4" | 💧 Light watering |
| Nov | — | 7.6" | 0" | ❄️ Dormant |
| Dec | — | 7.7" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Columbia 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 — Columbia County, OR
Daikon Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Direct Sow | March 31 | Mar 31 – Apr 21 |
| Harvest | May 26 | May 26 – Jun 23 |
| Fall Sowing | August 20 | Aug 20 – Sep 3 |
Plant 0.5" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Direct Sow |
| April | Direct Sow |
| May | Harvest |
| June | Harvest |
| July | — |
| August | Fall Sowing |
| September | Fall Sowing |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1"/week · Only during dry spells
📅 Days to Maturity
50–70 days
🧪 Soil pH
Needs 5.8–7 · Your soil: acceptable
🗺️ USDA Zone
Zone 8b
📆 Growing Season
198 days in Columbia County
Growing Tips for Daikon in Columbia County
Direct sow Daikon outdoors after April 14 in Columbia County when soil has warmed and frost danger has passed.
Common pests for Daikon 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 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 Columbia County, OR?
Columbia County is in Zone 8b with an average last frost of April 14. Plan your Daikon planting based on this frost date — see the calendar above for exact timing.
What planting zone is Columbia County, OR?
Columbia County, Oregon is in USDA Hardiness Zone 8b. The average last spring frost is April 14 and first fall frost is October 29.
Your Columbia County Garden Planner — Free
A 24-page printable planner built for Columbia County (Zone 8b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.