When to Plant Yam in Los Angeles County, CA
Top priorities for Los Angeles County, California gardeners in May
Each item below is timed to Los Angeles County, California's frost dates and soil temperatures. Skip nothing, stress about nothing.
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Start yam under lights
These need a head start before your last frost (April 3). Sow into cells now so you're ready to transplant in a few weeks.
True yams are tropical tubers distinct from sweet potatoes, producing large starchy roots that can weigh several pounds. They are a staple food in tropical regions worldwide.
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 Yam during the growing season. With low rainfall, drip irrigation is essential for growing Yam 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 Yam's growing requirements.
Soil pH
Your soil pH (5.8–7.5) is more alkaline than Yam prefers (5.5–6.5). Add sulfur or peat moss to lower pH.
Soil Texture
The loam soil in Los Angeles County is excellent for Yam — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.1%). Annual compost additions will help Yam.
How to Plant Yam
Plant Water Budget
Water stress score is 10/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Yam
Yam needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Yam Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 2.4" | 0" | ❄️ Dormant |
| Feb | — | 2.5" | 0" | ❄️ Dormant |
| Mar | — | 2.2" | 0" | ❄️ Dormant |
| Apr | 4.3" | 1.2" | 3.1" | 🚿 Regular watering |
| May | 4.3" | 0.4" | 3.9" | 🚿 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" | 0.6" | 3.7" | 🚿 Regular watering |
| Nov | 4.3" | 1.3" | 3" | 🚿 Regular 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.
Yam 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.
Yam Planting Timeline — Los Angeles County, CA
Yam Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 20 | Feb 20 – Mar 6 |
| Transplant Outdoors | April 10 | Apr 10 – Apr 24 |
| Direct Sow | April 3 | Apr 3 – Apr 24 |
| Harvest | October 9 | Oct 9 – Mar 26 |
Plant 0.5" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | Harvest |
| February | Start Indoors Harvest |
| March | Start Indoors Harvest |
| April | Transplant Outdoors Direct Sow |
| May | — |
| June | — |
| July | — |
| August | — |
| September | — |
| October | Harvest |
| November | Harvest |
| December | Harvest |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1"/week · 2-3 times/week
📅 Days to Maturity
180–330 days
🧪 Soil pH
Needs 5.5–6.5 · Your soil: too_alkaline
🗺️ USDA Zone
Zone 10b
📆 Growing Season
232 days in Los Angeles County
Growing Tips for Yam in Los Angeles County
Direct sow Yam outdoors after April 03 in Los Angeles County when soil has warmed and frost danger has passed.
Your 232.0-day growing season in Los Angeles County is tight for Yam (180.0-330.0 days to maturity). Start indoors and choose early-maturing varieties.
Los Angeles County receives only 13" of rain annually. Yam needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.
General growing tips
Plant tuber pieces in mounds of loose, rich soil. Provide sturdy trellising for climbing vines. Yams require a long, warm growing season of 8-11 months. Harvest when vines die back.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Yam in Other Locations
Frequently Asked Questions
When should I plant Yam in Los Angeles County, CA?
Los Angeles County is in Zone 10b with an average last frost of April 3. Plan your Yam 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.