When to Plant Scallions in Kern County, CA
Kern County, California gardeners: here's your May plan
Welcome to May in Zone 9b. These are the moves that will have the biggest impact on your growing season.
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Collect scallions at their peak
If you can't use it all right away, check the food-preservation section of your planner.
Scallions (green onions) are mild-flavored alliums harvested for their slender green tops and white bases. They are quick-growing and perfect for succession planting.
Kern County, California is in USDA Zone 9b. The average last spring frost is February 28 and the first fall frost is November 29, giving you a growing season of approximately 274 days.
At an elevation of 389 feet, Kern County receives approximately 16.9 inches of rainfall annually with predominantly loam soil. Summer highs average 102°F, so Scallions may need afternoon shade and extra watering during peak heat. With low rainfall, drip irrigation is essential for growing Scallions successfully. Mulch heavily to conserve soil moisture.
Kern County Soil Profile
Soil Type
Loam
Soil pH
6.2-7.7
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.
Soil Compatibility in Kern County
How your county's soil matches Scallions's growing requirements.
Soil pH
Your soil pH (6.2–7.7) overlaps with Scallions's range (6.0–7.0), though not a perfect match.
Soil Texture
The loam soil in Kern County is excellent for Scallions — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Scallions.
Organic Matter
Organic matter is moderate (2.3%). Annual compost additions will help Scallions.
How to Plant Scallions
Fall planting: Sow 8 weeks before your first frost date for a fall harvest.
Succession Planting Scallions
Sow every 5.7 weeks. Last sowing by Sep 20 to harvest before frost.
For a dedicated fall crop, sow by Oct 04.
Plant Water Budget
Water stress score is 8/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Scallions
Scallions needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Scallions Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 3.9" | 0" | ❄️ Dormant |
| Feb | 4.3" | 3.4" | 0.9" | 💧 Light watering |
| Mar | 4.3" | 2.4" | 1.9" | 💧 Light watering |
| Apr | 4.3" | 1.2" | 3.1" | 🚿 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" | 0.2" | 4.1" | 🚿 Regular watering |
| Oct | 4.3" | 0.7" | 3.6" | 🚿 Regular watering |
| Nov | 4.3" | 1.7" | 2.6" | 🚿 Regular watering |
| Dec | — | 2.8" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Feb–Nov in Kern County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Scallions 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.
Scallions Planting Timeline — Kern County, CA
Scallions Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | January 31 | Jan 31 – Feb 14 |
| Transplant Outdoors | February 28 | Feb 28 – Mar 14 |
| Direct Sow | February 7 | Feb 7 – Feb 28 |
| Harvest | April 25 | Apr 25 – May 23 |
| Fall Sowing | October 4 | Oct 4 – Oct 18 |
Plant 0.5" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | Start Indoors |
| February | Start Indoors Transplant Outdoors Direct Sow |
| March | Transplant Outdoors |
| April | Harvest |
| May | Harvest |
| June | — |
| July | — |
| August | — |
| September | — |
| October | Fall Sowing |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1"/week · 2-3 times/week
📅 Days to Maturity
50–70 days
🧪 Soil pH
Needs 6–7 · Your soil: acceptable
🗺️ USDA Zone
Zone 9b
📆 Growing Season
274 days in Kern County
Growing Tips for Scallions in Kern County
Direct sow Scallions outdoors after February 28 in Kern County when soil has warmed and frost danger has passed.
With summer highs reaching 102°F in Kern County, provide afternoon shade for Scallions and water deeply in the morning.
Common pests for Scallions in this region include onion maggots and thrips. Use row covers early in the season and inspect plants weekly.
Kern County receives only 17" of rain annually. Scallions needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.
General growing tips
Direct sow every 3 weeks for continuous harvest. Thin to 1 inch apart or grow in clusters. Harvest when pencil-thick by pulling or cutting at soil level.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Scallions in Other Locations
Frequently Asked Questions
When should I plant Scallions in Kern County, CA?
Kern County is in Zone 9b with an average last frost of February 28. Plan your Scallions planting based on this frost date — see the calendar above for exact timing.
What planting zone is Kern County, CA?
Kern County, California is in USDA Hardiness Zone 9b. The average last spring frost is February 28 and first fall frost is November 29.
Your Kern County Garden Planner — Free
A 24-page printable planner built for Kern County (Zone 9b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.