When to Plant Radish in Island County, WA
Radishes are one of the fastest-growing vegetables, with some varieties ready in under a month. They come in round, elongated, and large winter types.
Island County, Washington is in USDA Zone 8a. The average last spring frost is March 30 and the first fall frost is November 3, giving you a growing season of approximately 218 days.
At an elevation of 9 feet, Island County receives approximately 45.5 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85°F, providing good warmth for Radish during the growing season.
Island County Soil Profile
Soil Type
Silt Loam
Soil pH
5.6-6.7
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.
Plant Water Budget
Radish Planting Timeline — Island County, WA
Radish Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Direct Sow | March 16 | Mar 16 – Apr 6 |
| Fall Sowing | August 25 | Aug 25 – Sep 8 |
| Harvest | April 13 | Apr 13 – May 4 |
Plant 0.5" deep · 2" apart · Rows 6" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Direct Sow |
| April | Direct Sow Harvest |
| May | Harvest |
| June | — |
| July | — |
| August | Fall Sowing |
| September | Fall Sowing |
| October | — |
| November | — |
| December | — |
Growing Conditions
Sun
Full Sun (6-8+ hours)
Water
Moderate — regular watering
Days to Maturity
22–35 days
Soil pH
6 – 7
USDA Zone
Zone 8a
Growing Season
218 days
Growing Tips for Island County
Direct sow every 1-2 weeks for continuous harvest. Do not transplant. Harvest spring radishes promptly to prevent them from becoming pithy and hot.
Companion Planting
Good Companions
Avoid Planting Near
Level Up Your Garden
Radish in Other Locations
Frequently Asked Questions
When should I plant Radish in Island County, WA?
Island County is in Zone 8a with an average last frost of March 30. Plan your Radish planting based on this frost date — see the calendar above for exact timing.
What planting zone is Island County, WA?
Island County, Washington is in USDA Hardiness Zone 8a. The average last spring frost is March 30 and first fall frost is November 3.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Island County gardeners in Zone 8a 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.