When to Plant Kai Lan in Benton County, WA
Kai lan (Chinese broccoli) is a brassica grown for its thick, glossy stems and small flower buds. It has a slightly bitter, broccoli-like flavor essential in Cantonese cooking.
Benton County, Washington is in USDA Zone 7a. The average last spring frost is April 3 and the first fall frost is October 27, giving you a growing season of approximately 207 days.
At an elevation of 2,633 feet, Benton County receives approximately 22.5 inches of rainfall annually with predominantly silt loam soil. Summer highs average 88°F, providing good warmth for Kai Lan during the growing season.
Benton County Soil Profile
Soil Type
Silt Loam
Soil pH
5.5-6.3
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
Kai Lan Planting Timeline — Benton County, WA
Kai Lan Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 27 | Feb 27 – Mar 13 |
| Transplant Outdoors | April 3 | Apr 3 – Apr 17 |
| Direct Sow | March 20 | Mar 20 – Apr 10 |
| Fall Sowing | August 18 | Aug 18 – Sep 1 |
| Harvest | May 22 | May 22 – Jun 19 |
Plant 0.5" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | Start Indoors Direct Sow |
| April | Transplant Outdoors 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
Moderate — regular watering
Days to Maturity
45–60 days
Soil pH
6 – 7.5
USDA Zone
Zone 7a
Growing Season
207 days
Growing Tips for Benton County
Direct sow in spring or fall. Harvest when flower buds first appear but before they open. Cut stems at the base to encourage side shoots. Prefers cool weather.
Companion Planting
Good Companions
Avoid Planting Near
Level Up Your Garden
Kai Lan in Other Locations
Frequently Asked Questions
When should I plant Kai Lan in Benton County, WA?
Benton County is in Zone 7a with an average last frost of April 3. Plan your Kai Lan planting based on this frost date — see the calendar above for exact timing.
What planting zone is Benton County, WA?
Benton County, Washington is in USDA Hardiness Zone 7a. The average last spring frost is April 3 and first fall frost is October 27.
Plan Your Garden with Confidence
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