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🍉 Growing Watermelon in Zone 10b

Zone 10b has a year-round growing season. Watermelon can be planted almost any time with proper planning. Last frost: Jan 28. First frost: Dec 22.

Planting Calendar

Indoor

Outdoor

Harvest

Dec 31Dec 22

Season: Jan 28 – Dec 22 (328 days)

Zone10b

Last FrostJan 28

First FrostDec 22

Season Length328 days

Days to Harvest90

SunFull Sun

Frost ToleranceNone

Spacing1/sqft (12" apart)

When to Plant Watermelon in Zone 10b

Start Seeds Indoors: Dec 31

Start Watermelon seeds indoors around Dec 31 (4 weeks before last frost). Optimal germination temperature: 85°F. Germinates in 4–12 days.

Transplant Outdoors: Feb 11

Transplant Watermelon seedlings outdoors after Feb 11. Wait until soil temperature reaches 70°F. Space plants at 1/sqft (12" apart). Harden off plants for a week before moving outside.

Harvest: Apr 27

First harvest approximately Apr 27 (~75 days from transplant). Continue harvesting until first frost (Dec 22).

Companion Planting

✅ Corn✅ Nasturtiums✅ Marigolds✅ Radishes

❌ Potatoes❌ Cucumbers

Watermelon in Other Zones

1a 1b 2a 2b 3a 3b 4a 4b 5a 5b 6a 6b 7a 7b 8a 8b 9a 9b 10a 10b 11a 11b 12a 12b 13a 13b

Frequently Asked Questions

When should I plant Watermelon in Zone 10b?

Start Watermelon seeds indoors around Dec 31. Transplant outdoors after Feb 11. Expect first harvest around Apr 27.

What is the last frost date for Zone 10b?

The average last spring frost date for Zone 10b is Jan 28. The first fall frost averages Dec 22, giving a 328-day growing season.

Can I grow Watermelon in Zone 10b?

Yes. Watermelon needs 90 days to harvest. Zone 10b has a 328-day growing season, which is sufficient.

What is the best month to plant Watermelon in Zone 10b?

The best time to start Watermelon in Zone 10b is Dec. Begin seeds indoors around Dec 31, then transplant outdoors after the last frost date of Jan 28.

What companion plants grow well with Watermelon?

Good companion plants for Watermelon include Corn, Nasturtiums, Marigolds, Radishes. Avoid planting Watermelon near Potatoes, Cucumbers.

How long does Watermelon take to harvest?

Watermelon takes approximately 90 days from planting to harvest. In Zone 10b, expect your first harvest around Apr 27.

Plan Your Watermelon Garden

Track Watermelon from seed to harvest with personalized frost dates, watering recommendations, and companion planting visualization.

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