When should I plant Rhubarb in Zone 10a?

Start Rhubarb seeds indoors around Dec 12. Transplant outdoors after Jan 23. Expect first harvest around Jan 23.

What is the last frost date for Zone 10a?

The average last spring frost date for Zone 10a is Feb 20. The first fall frost averages Dec 1, giving a 284-day growing season.

Can I grow Rhubarb in Zone 10a?

Yes. Rhubarb needs 90 days to harvest. Zone 10a has a 284-day growing season, which is sufficient.

Growing Rhubarb in Zone 10a

Zone 10a has a year-round growing season. Rhubarb can be planted almost any time with proper planning. Last frost: Feb 20. First frost: Dec 1.

Planting Calendar

Indoor

Outdoor

Harvest

Dec 12Dec 1

Season: Feb 20 – Dec 1 (284 days)

Zone10a

Last FrostFeb 20

First FrostDec 1

Season Length284 days

Days to Harvest90

SunFull Sun

Frost ToleranceHeavy

Spacing1/sqft (12" apart)

When to Plant Rhubarb in Zone 10a

Start Seeds Indoors: Dec 12

Start Rhubarb seeds indoors around Dec 12 (10 weeks before last frost). Optimal germination temperature: 65°F. Germinates in 7–21 days.

Transplant Outdoors: Jan 23

Transplant Rhubarb seedlings outdoors after Jan 23. Wait until soil temperature reaches 40°F. Space plants at 1/sqft (12" apart). Harden off plants for a week before moving outside.

Harvest: Jan 23

First harvest approximately Jan 23 (~365 days from transplant). Continue harvesting until first frost (Dec 1). Rhubarb can overwinter in mild climates for continued harvest.

Rhubarb 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

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