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When to Plant Sorrel in USDA Zone 4a

Zone 4a Zone 4a May

Your May planting checklist for Zone 4a

May rewards gardeners who work with the weather, not against it. Here's how to stay in step this month in Zone 4a.

Avg. last frost May 13
Avg. first frost September 28
  1. Move sorrel into the garden

    Frost risk is low now in Zone 4a. If you've been covering beds overnight, you can stop.

  2. Outdoor sowing time: sorrel

    These tolerate cool soil, so you're not gambling by sowing now.

Before June arrives, get these ready
  • Starting indoors: sorrel
  • First harvests: sorrel
Get your free Zone 4a 2026 Planting Guide →

Sorrel is a perennial herb with tangy, lemon-flavored arrow-shaped leaves. It is one of the first greens to emerge in spring and is used in soups and salads.

In Zone 4a, the average last spring frost is around May 6 and the first fall frost is around September 28, giving you a growing season of approximately 145 days.

Zone 4a Short season
145 days
Last Spring Frost May 6
145 growing days
First Fall Frost September 28

Sorrel Planting Timeline — Zone 4a

Where Is USDA Zone 4a?

The map below highlights the states that contain Zone 4a. Click any state to see the Sorrel planting schedule for that location.

Prints a clean, ink-friendly version without maps or navigation.

Sorrel Planting Calendar — Zone 4a

Activity When Date Range
Start Indoors March 25 Mar 25 – Apr 8
Transplant Outdoors April 29 Apr 29 – May 13
Direct Sow April 29 Apr 29 – May 20
Harvest June 10 Jun 10 – Aug 12
Fall Sowing July 6 Jul 6 – Jul 20

Plant 0.5" deep · 8" apart · Rows 12" apart

Month-by-Month Timeline

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

Free Zone 4a Planting Calendar PDF

Know exactly when to plant every crop in your zone. Get a printable month-by-month calendar customized for Zone 4a with start dates, transplant windows, and harvest times.

Instant PDF download. No spam, unsubscribe any time.

Growing Conditions

Sun

Partial Shade (3-6 hours)

💧 Water

Moderate — regular watering

Days to Maturity

40–60 days

Soil pH

5.5 – 7

Zone Temperature Range

°F to °F average annual minimum

Growing Season

145 days (Zone average)

Planting Specifications

Planting Depth0.5 inches
Plant Spacing8 inches apart
Row Spacing12 inches between rows

Succession Planting Sorrel in Zone

4
successive plantings in Zone 's ~145-day season

Sow every 4.6 weeks for continuous harvest throughout the season.

Growing Tips for Sorrel in Zone

Zone has a short growing season (~145 days). Start Sorrel indoors early and use season-extension techniques like row covers and cold frames.

Direct sow in early spring or fall. Remove flower stalks promptly to encourage leaf production. Divide clumps every 3-4 years. Young leaves have the best flavor.

Companion Planting

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Saving Sorrel Seeds

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Fabric Grow Bags $10-25

Breathable fabric pots that promote healthy root growth and prevent overwatering.

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Built-in reservoir keeps herbs and greens consistently watered with less effort.

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Seed Starting Trays $8-20

Start seeds indoors with reusable cell trays and humidity domes.

Related Plants

Frequently Asked Questions

When should I plant Sorrel in Zone 4a?

In Zone 4a, plan your Sorrel planting around the average last frost date of May 6. Start seeds indoors around March 25. Direct sow outdoors around April 29. Transplant seedlings around April 29.

Can Sorrel grow in Zone 4a?

Yes, Sorrel can grow well in Zone 4a, hardy in USDA zones 3a through 9b. Zone 4a has a growing season of approximately 145 days, which is sufficient for Sorrel (40-60 days to maturity).

When can I harvest Sorrel in Zone 4a?

In Zone 4a, expect to harvest Sorrel from June 10 – August 12. Sorrel takes 40-60 days from planting to harvest.

What is the last frost date for Zone 4a?

The average last spring frost in Zone 4a is around May 6, and the first fall frost is around September 28. This gives a growing season of approximately 145 days. These are 50% probability dates — actual frost dates vary year to year.

What should I plant next to Sorrel?

Good companion plants for Sorrel include Strawberries, Lettuce, Spinach. These companions can help with pest control, pollination, and nutrient sharing.

🌱

Your Free Printable Garden Planner

A 24-page printable planner tailored to your zone. Planting dates, monthly task lists, harvest log, seed inventory, and succession charts — everything you need to plan a full season.

Instant PDF download. No spam, unsubscribe any time.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals, University Cooperative Extension planting guides. Planting dates are estimates based on average frost dates — 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.