When to Plant Borage in Los Angeles County, CA
Your May gardening checklist
A quick May briefing for Los Angeles County, California gardeners — what's urgent, what's next, and what can wait.
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Time to start borage inside
Label every cell. You will absolutely forget which is which otherwise.
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Basket week: borage
Morning harvests are best — cooler temperatures mean crisper produce and longer fridge life.
Get ahead of June
- First harvests: borage
Borage is a self-seeding annual herb with star-shaped blue flowers that attract pollinators. Its leaves have a cucumber-like flavor and the flowers are edible.
Los Angeles County, California is in USDA Zone 10b. The average last spring frost is April 3 and the first fall frost is November 21, giving you a growing season of approximately 232 days.
At an elevation of 1,315 feet, Los Angeles County receives approximately 12.9 inches of rainfall annually with predominantly loam soil. Summer highs average 87°F, providing good warmth for Borage during the growing season. With low rainfall, drip irrigation is essential for growing Borage successfully. Mulch heavily to conserve soil moisture.
Los Angeles County Soil Profile
Soil Type
Loam
Soil pH
5.8-7.5
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 Los Angeles County
How your county's soil matches Borage's growing requirements.
Soil pH
Your soil pH (5.8–7.5) overlaps with Borage's range (6.0–7.0), though not a perfect match.
Soil Texture
The loam soil in Los Angeles County is excellent for Borage — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.1%). Annual compost additions will help Borage.
How to Plant Borage
Fall planting: Sow 8 weeks before your first frost date for a fall harvest.
Succession Planting Borage
Sow every 5.7 weeks. Last sowing by Sep 22 to harvest before frost.
For a dedicated fall crop, sow by Sep 26.
Plant Water Budget
Water stress score is 10/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Borage
Borage needs approximately 0.5 inches of water per week (2.2" per month). Here's how your county's rainfall compares month by month.
| Month | Borage Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 2.4" | 0" | ❄️ Dormant |
| Feb | — | 2.5" | 0" | ❄️ Dormant |
| Mar | — | 2.2" | 0" | ❄️ Dormant |
| Apr | 2.2" | 1.2" | 1" | 💧 Light watering |
| May | 2.2" | 0.4" | 1.8" | 🚿 Regular watering |
| Jun | 2.2" | 0.1" | 2.1" | 🚿 Regular watering |
| Jul | 2.2" | 0" | 2.2" | 🚿 Regular watering |
| Aug | 2.2" | 0" | 2.2" | 🚿 Regular watering |
| Sep | 2.2" | 0.2" | 2" | 🚿 Regular watering |
| Oct | 2.2" | 0.6" | 1.6" | 🚿 Regular watering |
| Nov | 2.2" | 1.3" | 0.9" | 💧 Light watering |
| Dec | — | 2.1" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Nov in Los Angeles County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Borage 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.
Borage Planting Timeline — Los Angeles County, CA
Borage Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 6 | Mar 6 – Mar 20 |
| Transplant Outdoors | March 27 | Mar 27 – Apr 10 |
| Direct Sow | March 13 | Mar 13 – Apr 3 |
| Harvest | May 22 | May 22 – Jul 10 |
| Fall Sowing | September 26 | Sep 26 – Oct 10 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors Transplant Outdoors Direct Sow |
| April | Transplant Outdoors Direct Sow |
| May | Harvest |
| June | Harvest |
| July | Harvest |
| August | — |
| September | Fall Sowing |
| October | Fall Sowing |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.5"/week · 1-2 times/week
📅 Days to Maturity
50–60 days
🧪 Soil pH
Needs 6–7 · Your soil: acceptable
🗺️ USDA Zone
Zone 10b
📆 Growing Season
232 days in Los Angeles County
Growing Tips for Borage in Los Angeles County
Direct sow Borage outdoors after April 03 in Los Angeles County when soil has warmed and frost danger has passed.
General growing tips
Direct sow in spring as borage does not transplant well. Allow some plants to go to seed for next year. Young leaves are best; older leaves become bristly.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Borage in Other Locations
Frequently Asked Questions
When should I plant Borage in Los Angeles County, CA?
Los Angeles County is in Zone 10b with an average last frost of April 3. Plan your Borage planting based on this frost date — see the calendar above for exact timing.
What planting zone is Los Angeles County, CA?
Los Angeles County, California is in USDA Hardiness Zone 10b. The average last spring frost is April 3 and first fall frost is November 21.
Your Los Angeles County Garden Planner — Free
A 24-page printable planner built for Los Angeles County (Zone 10b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.