Rhubarb illustration

Growing Rhubarb in Zone 1b

Zone 1b has harsh winters and a short growing season. Start Rhubarb early indoors to maximize your harvest window. Last frost: May 25. First frost: Aug 28.

Planting Calendar

Indoor
Outdoor
Harvest
Mar 16Aug 28

Season: May 25 – Aug 28 (95 days)

Zone1b
Last FrostMay 25
First FrostAug 28
Season Length95 days
Days to Harvest90
SunFull Sun
Frost ToleranceHeavy
Spacing1/sqft (12" apart)

When to Plant Rhubarb in Zone 1b

Start Seeds Indoors: Mar 16

Start Rhubarb seeds indoors around Mar 16 (10 weeks before last frost). Optimal germination temperature: 65°F. Germinates in 7–21 days.

Transplant Outdoors: Apr 27

Transplant Rhubarb seedlings outdoors after Apr 27. Wait until soil temperature reaches 40°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 (~365 days from transplant). Continue harvesting until first frost (Aug 28). Rhubarb can overwinter in mild climates for continued harvest.

Frequently Asked Questions

When should I plant Rhubarb in Zone 1b?

Start Rhubarb seeds indoors around Mar 16. Transplant outdoors after Apr 27. Expect first harvest around Apr 27.

What is the last frost date for Zone 1b?

The average last spring frost date for Zone 1b is May 25. The first fall frost averages Aug 28, giving a 95-day growing season.

Can I grow Rhubarb in Zone 1b?

Yes. Rhubarb needs 90 days to harvest. Zone 1b has a 95-day growing season, which is sufficient.

What is the best month to plant Rhubarb in Zone 1b?

The best time to start Rhubarb in Zone 1b is Mar. Begin seeds indoors around Mar 16, then transplant outdoors after the last frost date of May 25.

How long does Rhubarb take to harvest?

Rhubarb takes approximately 90 days from planting to harvest. In Zone 1b, expect your first harvest around Apr 27.

Plan Your Rhubarb Garden

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

Start Free Rhubarb Growing Guide