When to Plant Sunflower in Calaveras County, CA
May in Calaveras County, California — your action list
May is a pivotal month for Calaveras County, California gardens. Focus on these tasks first and you'll set up the rest of the season for success.
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Start sunflower under lights
Label every cell. You will absolutely forget which is which otherwise.
Before June arrives, get these ready
- First harvests: sunflower
Sunflowers are tall, cheerful annuals grown for their edible seeds and as pollinator magnets. They come in sizes from 2-foot dwarfs to 12-foot giants.
Calaveras County, California is in USDA Zone 9a. The average last spring frost is April 8 and the first fall frost is November 12, giving you a growing season of approximately 218 days.
At an elevation of 2,363 feet, Calaveras County receives approximately 25 inches of rainfall annually with predominantly loam soil. Summer highs average 83°F, so choose short-season varieties of Sunflower to ensure they mature before fall.
Calaveras County Soil Profile
Soil Type
Loam
Soil pH
6.5-7.6
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 Calaveras County
How your county's soil matches Sunflower's growing requirements.
Soil pH
Your soil pH (6.5–7.6) overlaps with Sunflower's range (6.0–7.5), though not a perfect match.
Soil Texture
The loam soil in Calaveras County is excellent for Sunflower — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.9%). Annual compost additions will help Sunflower.
How to Plant Sunflower
Succession Planting Sunflower
Sow every 8 weeks. Last sowing by Aug 04 to harvest before frost.
Plant Water Budget
Water stress score is 8/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Sunflower
Sunflower 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 | Sunflower Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 5.4" | 0" | ❄️ Dormant |
| Feb | — | 4.8" | 0" | ❄️ Dormant |
| Mar | — | 4" | 0" | ❄️ Dormant |
| Apr | 2.2" | 2.4" | 0" | ✅ Rainfall sufficient |
| May | 2.2" | 0.7" | 1.5" | 🚿 Regular watering |
| Jun | 2.2" | 0.2" | 2" | 🚿 Regular watering |
| Jul | 2.2" | 0" | 2.2" | 🚿 Regular watering |
| Aug | 2.2" | 0" | 2.2" | 🚿 Regular watering |
| Sep | 2.2" | 0.3" | 1.9" | 🚿 Regular watering |
| Oct | 2.2" | 1" | 1.2" | 🚿 Regular watering |
| Nov | 2.2" | 2.3" | 0" | ✅ Rainfall sufficient |
| Dec | — | 3.9" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Nov in Calaveras County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Sunflower 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.
Sunflower Planting Timeline — Calaveras County, CA
Sunflower Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 25 | Feb 25 – Mar 11 |
| Transplant Outdoors | April 15 | Apr 15 – Apr 29 |
| Direct Sow | April 8 | Apr 8 – Apr 29 |
| Harvest | June 24 | Jun 24 – Aug 12 |
Plant 1" deep · 18" apart · Rows 30" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | Start Indoors |
| April | Transplant Outdoors Direct Sow |
| May | — |
| June | Harvest |
| July | Harvest |
| August | Harvest |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.5"/week · Only during dry spells
📅 Days to Maturity
70–100 days
🧪 Soil pH
Needs 6–7.5 · Your soil: acceptable
🗺️ USDA Zone
Zone 9a
📆 Growing Season
218 days in Calaveras County
Growing Tips for Sunflower in Calaveras County
Direct sow Sunflower outdoors after April 08 in Calaveras County when soil has warmed and frost danger has passed.
Common pests for Sunflower in this region include aphids and slugs. Use row covers early in the season and inspect plants weekly.
General growing tips
Direct sow after last frost. Stake tall varieties in windy areas. Harvest seed heads when the back turns brown and seeds are plump. Dry heads upside down.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Sunflower in Other Locations
Frequently Asked Questions
When should I plant Sunflower in Calaveras County, CA?
Calaveras County is in Zone 9a with an average last frost of April 8. Plan your Sunflower planting based on this frost date — see the calendar above for exact timing.
What planting zone is Calaveras County, CA?
Calaveras County, California is in USDA Hardiness Zone 9a. The average last spring frost is April 8 and first fall frost is November 12.
Your Calaveras County Garden Planner — Free
A 24-page printable planner built for Calaveras County (Zone 9a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.