Mustard Greens illustration

Growing Mustard Greens in Zone 10b

Zone 10b has a year-round growing season. Mustard Greens 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) · Succession: plant every 2 weeks (up to 20x)

Zone10b
Last FrostJan 28
First FrostDec 22
Season Length328 days
Days to Harvest45
SunPart Sun / Part Shade
Frost ToleranceModerate
Spacing4/sqft (6" apart)

When to Plant Mustard Greens in Zone 10b

Start Seeds Indoors: Dec 31

Start Mustard Greens seeds indoors around Dec 31 (4 weeks before last frost). Optimal germination temperature: 65°F. Germinates in 4–8 days.

Transplant Outdoors: Jan 14

Transplant Mustard Greens seedlings outdoors after Jan 14. Wait until soil temperature reaches 40°F. Space plants at 4/sqft (6" apart). Harden off plants for a week before moving outside.

Harvest: Feb 28

First harvest approximately Feb 28 (~45 days from planting). Continue harvesting until first frost (Dec 22).

Fall Planting: Nov 10

For a fall harvest, plant Mustard Greens around Nov 10 (6 weeks before first frost).

Frequently Asked Questions

When should I plant Mustard Greens in Zone 10b?

Start Mustard Greens seeds indoors around Dec 31. Transplant outdoors after Jan 14. Expect first harvest around Feb 28.

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 Mustard Greens in Zone 10b?

Yes. Mustard Greens needs 45 days to harvest. Zone 10b has a 328-day growing season, which is sufficient. You can plant up to 20 successions.

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

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

How long does Mustard Greens take to harvest?

Mustard Greens takes approximately 45 days from planting to harvest. In Zone 10b, expect your first harvest around Feb 28.

Plan Your Mustard Greens Garden

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

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