When to Plant Kai Lan in Mercer County, NJ
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.
Mercer County, New Jersey is in USDA Zone 7a. The average last spring frost is April 12 and the first fall frost is October 29, giving you a growing season of approximately 200 days.
At an elevation of 4 feet, Mercer County receives approximately 45.5 inches of rainfall annually with predominantly silt loam soil. Summer highs average 90°F, providing good warmth for Kai Lan during the growing season.
Mercer County Soil Profile
Soil Type
Silt Loam
Soil pH
5-6.7
Drainage
Well Drained
Monthly Watering Guide for Kai Lan
Kai Lan needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Kai Lan Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 3.1" | 0" | ❄️ Dormant |
| Feb | — | 3.3" | 0" | ❄️ Dormant |
| Mar | — | 4.1" | 0" | ❄️ Dormant |
| Apr | 4.3" | 4.1" | 0.2" | 💧 Light watering |
| May | 4.3" | 4.1" | 0.2" | 💧 Light watering |
| Jun | 4.3" | 3.8" | 0.5" | 💧 Light watering |
| Jul | 4.3" | 4.8" | 0" | ✅ Rainfall sufficient |
| Aug | 4.3" | 4.1" | 0.2" | 💧 Light watering |
| Sep | 4.3" | 3.5" | 0.8" | 💧 Light watering |
| Oct | 4.3" | 3.8" | 0.5" | 💧 Light watering |
| Nov | — | 3.8" | 0" | ❄️ Dormant |
| Dec | — | 3" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Mercer County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Kai Lan Planting Timeline — Mercer County, NJ
Kai Lan Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 8 | Mar 8 – Mar 22 |
| Transplant Outdoors | April 12 | Apr 12 – Apr 26 |
| Direct Sow | March 29 | Mar 29 – Apr 19 |
| Harvest | May 31 | May 31 – Jun 28 |
| 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 | 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
Needs 6–7.5 · Your soil: N/A
🗺️ USDA Zone
Zone 7a
📆 Growing Season
200 days in Mercer County
Growing Tips for Mercer 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
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Kai Lan in Other Locations
Frequently Asked Questions
When should I plant Kai Lan in Mercer County, NJ?
Mercer County is in Zone 7a with an average last frost of April 12. Plan your Kai Lan planting based on this frost date — see the calendar above for exact timing.
What planting zone is Mercer County, NJ?
Mercer County, New Jersey is in USDA Hardiness Zone 7a. The average last spring frost is April 12 and first fall frost is October 29.
Plan Your Garden with Confidence
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