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When to Plant Bitter Melon in Fresno County, CA

Fresno County, California Zone 9b May

This month in Fresno County, California

Your garden in Fresno County, California is working on a schedule, even when you're not. Here's where you should be this May.

Avg. last frost March 2
Avg. first frost November 23
Soil temp (4") 72°F
Watering Critical
Pest pressure High
Daylight 14 hrs
  1. Bring in the bitter melon

    This is the payoff month. Bring a basket, bring a friend, and get into the beds.

Coming up in June — start thinking about
  • First harvests: bitter melon

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Bitter melon is a tropical vine producing warty, bitter fruits used in Asian and Indian cuisine. The intense bitterness is prized for its culinary and health properties.

Fresno County, California is in USDA Zone 9b. The average last spring frost is March 2 and the first fall frost is November 23, giving you a growing season of approximately 266 days.

At an elevation of 2,276 feet, Fresno County receives approximately 14.9 inches of rainfall annually with predominantly loam soil. Summer highs average 100°F, so Bitter Melon may need afternoon shade and extra watering during peak heat. With low rainfall, drip irrigation is essential for growing Bitter Melon successfully. Mulch heavily to conserve soil moisture.

Fresno County, CA (Zone 9b) Long season
266 days
Last Spring Frost March 2
266 growing days
First Fall Frost November 23

Fresno County Soil Profile

Soil Type

Loam

Soil pH

6.5-7.5

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (155 days to spare)
Start indoors: Jan 5 Transplant: Feb 23 🍅 Harvest: Apr 27 – Jun 8
Recommended (50%) ✓ Fits season (154 days to spare)
Start indoors: Jan 19 Transplant: Mar 9 🍅 Harvest: May 11 – Jun 22
Safe Start (90%) ✓ Fits season (106 days to spare)
Start indoors: Mar 30 Transplant: May 18 🍅 Harvest: Jul 20 – Aug 31

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 Fresno County

How your county's soil matches Bitter Melon's growing requirements.

Soil pH

Your soil pH (6.5–7.5) overlaps with Bitter Melon's range (6.0–7.0), though not a perfect match.

Soil Texture

The loam soil in Fresno County is excellent for Bitter Melon — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (3.2%). Annual compost additions will help Bitter Melon.

How to Plant Bitter Melon

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

Succession Planting Bitter Melon

5
successive plantings in your 266-day season

Sow every 6.9 weeks. Last sowing by Aug 25 to harvest before frost.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.2″/week
You supply
0.9″/week
Watering frequency 2-3 times/week
Season total 2,173 gal / 100 sq ft
Drought risk

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

Monthly Watering Guide for Bitter Melon

Bitter Melon needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Bitter Melon Needs Rainfall You Supplement Action
Jan 2.8" 0" ❄️ Dormant
Feb 3.3" 0" ❄️ Dormant
Mar 4.3" 2.3" 2" 💧 Light watering
Apr 4.3" 1" 3.3" 🚿 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 2.8" 0" ❄️ Dormant

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

Bitter Melon 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.

Bitter Melon needs ~1,875 GDD — county provides 6,650 GDD Excellent fit

Bitter Melon Planting Timeline — Fresno County, CA

Bitter Melon Planting Calendar

Activity When Date Range
Start Indoors January 19 Jan 19 – Feb 2
Transplant Outdoors March 9 Mar 9 – Mar 23
Direct Sow March 2 Mar 2 – Mar 23
Harvest May 11 May 11 – Jun 22

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1"/week · 2-3 times/week

📅 Days to Maturity

60–90 days

🧪 Soil pH

Needs 6–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 9b

📆 Growing Season

266 days in Fresno County

Growing Tips for Bitter Melon in Fresno County

Direct sow Bitter Melon outdoors after March 02 in Fresno County when soil has warmed and frost danger has passed.

With summer highs reaching 100°F in Fresno County, provide afternoon shade for Bitter Melon and water deeply in the morning.

Common pests for Bitter Melon in this region include squash vine borer and cucumber beetles. Use row covers early in the season and inspect plants weekly.

Fresno County receives only 15" of rain annually. Bitter Melon needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.

General growing tips

Start seeds indoors 4 weeks before last frost. Provide a trellis for climbing. Harvest fruits while still green and firm. Reduce bitterness by salting sliced fruit before cooking.

Companion Planting

Good Companions

Avoid Planting Near

  • Potatoes

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Bitter Melon in Fresno County, CA?

Fresno County is in Zone 9b with an average last frost of March 2. Plan your Bitter Melon planting based on this frost date — see the calendar above for exact timing.

What planting zone is Fresno County, CA?

Fresno County, California is in USDA Hardiness Zone 9b. The average last spring frost is March 2 and first fall frost is November 23.

🌱

Your Fresno County Garden Planner — Free

A 24-page printable planner built for Fresno 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.

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Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Fresno 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.