Blog

When to Plant Eggplant in Plumas County, CA

Plumas County, California Zone 7b May

May in Plumas County, California — your action list

May rewards gardeners who work with the weather, not against it. Here's how to stay in step this month in Plumas County, California.

Avg. last frost May 20
Avg. first frost October 8
Soil temp (4") 64°F
Watering Critical
Pest pressure Low
Daylight 14.2 hrs
  1. Plant eggplant from seed, right in the garden

    Keep the top inch of soil moist until germination — a gentle morning watering for 5–7 days does the job.

June prep starts now
  • Transplants going out: eggplant

Instant PDF download. No spam, unsubscribe any time.

Eggplant is a heat-loving solanaceous crop that produces glossy fruits in purple, white, or striped varieties. It requires long, warm growing seasons for best production.

Plumas County, California is in USDA Zone 7b. The average last spring frost is May 20 and the first fall frost is October 8, giving you a growing season of approximately 141 days.

At an elevation of 1,185 feet, Plumas County receives approximately 30.9 inches of rainfall annually with predominantly loam soil. Summer highs average 82°F, so choose short-season varieties of Eggplant to ensure they mature before fall.

Plumas County, CA (Zone 7b) Short season
141 days
Last Spring Frost May 20
141 growing days
First Fall Frost October 8
Share this guide:

Plumas County Soil Profile

Soil Type

Loam

Soil pH

6.6-7.6

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Start indoors: Mar 9 Transplant: May 25 🍅 Harvest: Aug 3 – Oct 5
Recommended (50%) ✗ May not fit
Start indoors: Mar 18 Transplant: Jun 3 🍅 Harvest: Aug 12 – Oct 14
Safe Start (90%) ✗ May not fit
Start indoors: Apr 6 Transplant: Jun 22 🍅 Harvest: Aug 31 – Nov 2

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 Plumas County

How your county's soil matches Eggplant's growing requirements.

Soil pH

Your soil pH (6.6–7.6) is more alkaline than Eggplant prefers (5.5–7.0). Add sulfur or peat moss to lower pH.

Soil Texture

The loam soil in Plumas County is excellent for Eggplant — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (2.5%). Annual compost additions will help Eggplant.

How to Plant Eggplant

1"
Planting Depth
30"
Between Plants
42"
Between Rows

Succession Planting Eggplant

2
successive plantings in your 141-day season

Sow every 7.4 weeks. Last sowing by Jul 15 to harvest before frost.

Plant Water Budget

Plant needs
1.1″/week
Rainfall provides
0.9″/week
You supply
0.2″/week
Watering frequency Only during dry spells
Season total 270 gal / 100 sq ft
Drought risk

Water stress score is 8/10 — consider drought-tolerant varieties and mulching

Monthly Watering Guide for Eggplant

Eggplant needs approximately 1.1 inches of water per week (4.8" per month). Here's how your county's rainfall compares month by month.

Month Eggplant Needs Rainfall You Supplement Action
Jan 6.9" 0" ❄️ Dormant
Feb 6.2" 0" ❄️ Dormant
Mar 5" 0" ❄️ Dormant
Apr 2.4" 0" ❄️ Dormant
May 4.8" 1" 3.8" 🚿 Regular watering
Jun 4.8" 0.2" 4.6" 🚿 Regular watering
Jul 4.8" 0" 4.8" 🚿 Regular watering
Aug 4.8" 0" 4.8" 🚿 Regular watering
Sep 4.8" 0.3" 4.5" 🚿 Regular watering
Oct 4.8" 1.2" 3.6" 🚿 Regular watering
Nov 3" 0" ❄️ Dormant
Dec 4.8" 0" ❄️ Dormant

Water needs are for active growing months only (May–Oct in Plumas County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Eggplant 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.

Eggplant needs ~862 GDD — county provides 1,621 GDD Excellent fit

Eggplant Planting Timeline — Plumas County, CA

Eggplant Planting Calendar

Activity When Date Range
Start Indoors March 18 Mar 18 – Apr 1
Transplant Outdoors June 3 Jun 3 – Jun 17
Direct Sow May 27 May 27 – Jun 17
Harvest August 12 Aug 12 – Oct 14

Plant 1" deep · 30" apart · Rows 42" apart

Month-by-Month Timeline

MonthActivities
January
February
March Start Indoors
April Start Indoors
May Direct Sow
June Transplant Outdoors Direct Sow
July
August Harvest
September Harvest
October Harvest
November
December
Share this guide:

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1.1"/week · Only during dry spells

📅 Days to Maturity

65–85 days

🧪 Soil pH

Needs 5.5–7 · Your soil: too_alkaline

🗺️ USDA Zone

Zone 7b

📆 Growing Season

141 days in Plumas County

Growing Tips for Eggplant in Plumas County

Direct sow Eggplant outdoors after May 20 in Plumas County when soil has warmed and frost danger has passed.

Common pests for Eggplant in this region include tomato hornworm and aphids. Use row covers early in the season and inspect plants weekly.

General growing tips

Start seeds indoors 8-10 weeks before last frost. Transplant only after nighttime temperatures stay above 55F. Mulch to retain moisture and warmth around roots.

Companion Planting

Good Companions

Avoid Planting Near

  • Fennel
  • Kohlrabi

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Eggplant in Plumas County, CA?

Plumas County is in Zone 7b with an average last frost of May 20. Plan your Eggplant planting based on this frost date — see the calendar above for exact timing.

What planting zone is Plumas County, CA?

Plumas County, California is in USDA Hardiness Zone 7b. The average last spring frost is May 20 and first fall frost is October 8.

🌱

Your Plumas County Garden Planner — Free

A 24-page printable planner built for Plumas County (Zone 7b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

Instant PDF download. No spam, unsubscribe any time.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Plumas County, CA. Local conditions may vary. Last updated: May 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.