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When to Plant Spinach in USDA Zone 10b

Zone 10b Zone 10b May

May in the garden — Zone 10b

Here's what deserves your attention in Zone 10b this month. Everything below is tailored to Zone 10b and timed around your local frost dates.

Avg. last frost February 13
Avg. first frost November 27
  1. Bring in the spinach

    This is the payoff month. Bring a basket, bring a friend, and get into the beds.

Get the full Zone 10b Garden Planner — free →
Spinach

Spinach is a nutrient-packed cool-season green that grows quickly in spring and fall. It is rich in iron, vitamins, and antioxidants and excellent raw or cooked.

In Zone 10b, the average last spring frost is around January 1 and the first fall frost is around December 31, giving you a growing season of approximately 364 days.

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Zone 10b Year-round
364 days
Last Spring Frost January 1
364 growing days
First Fall Frost December 31

Spinach Planting Timeline — Zone 10b

Where Is USDA Zone 10b?

The map below highlights the states that contain Zone 10b. Click any state to see the Spinach planting schedule for that location.

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

Spinach Planting Calendar — Zone 10b

Activity When Date Range
Start Indoors December 4 Dec 4 – Dec 18
Transplant Outdoors January 1 Jan 1 – Jan 15
Direct Sow December 11 Dec 11 – Jan 1
Harvest February 5 Feb 5 – Apr 9
Fall Sowing November 5 Nov 5 – Nov 19

Plant 0.5" deep · 6" apart · Rows 12" apart

Month-by-Month Timeline

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

Free Zone 10b Planting Calendar PDF

Know exactly when to plant every crop in your zone. Get a printable month-by-month calendar customized for Zone 10b with start dates, transplant windows, and harvest times.

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Growing Conditions

Sun

Partial Shade (3-6 hours)

💧 Water

0.7"/week · Moderate — regular watering

Days to Maturity

35–50 days

Soil pH

6.5 – 7.5

Zone Temperature Range

°F to °F average annual minimum

Growing Season

364 days (Zone average)

Planting Specifications

Planting Depth0.5 inches
Plant Spacing6 inches apart
Row Spacing12 inches between rows

Succession Planting Spinach in Zone

12
successive plantings in Zone 's ~364-day season

Sow every 4 weeks for continuous harvest throughout the season.

Growing Tips for Spinach in Zone

Zone has a short growing season (~364 days). Start Spinach indoors early and use season-extension techniques like row covers and cold frames.

Direct sow as soon as soil can be worked in spring. Plant in partial shade for summer crops to delay bolting. Succession plant every 2 weeks for continuous harvest.

Companion Planting

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Saving Spinach Seeds

🌾 Save Your Own Spinach Seeds
Life Cycle Annual
Pollination Wind Pollinated
How to Collect Let plants bolt. Harvest seed stalks when seeds turn tan.
Storage Store airtight; viable 5 years at 35°F, under 45% humidity.

Wind pollinated — isolate 1/2 mile for purity. Easy to let bolt in heat.

Recommended for Your Garden

🌱
Seed Starting Trays $8-20

Start seeds indoors with reusable cell trays and humidity domes.

🧪
Soil Test Kit $12-25

Test your soil pH, nitrogen, phosphorus, and potassium levels before planting.

🏷️
Garden Plant Markers $6-12

Keep your garden organized with durable, weather-resistant plant labels.

Related Plants

Frequently Asked Questions

When should I plant Spinach in Zone 10b?

In Zone 10b, plan your Spinach planting around the average last frost date of January 1. Start seeds indoors around December 4. Direct sow outdoors around December 11. Transplant seedlings around January 1.

Can Spinach grow in Zone 10b?

Yes, Spinach can grow well in Zone 10b, hardy in USDA zones 2a through 10b. Zone 10b has a growing season of approximately 364 days, which is sufficient for Spinach (35-50 days to maturity).

When can I harvest Spinach in Zone 10b?

In Zone 10b, expect to harvest Spinach from February 5 – April 9. Spinach takes 35-50 days from planting to harvest.

What is the last frost date for Zone 10b?

The average last spring frost in Zone 10b is around January 1, and the first fall frost is around December 31. This gives a growing season of approximately 364 days. These are 50% probability dates — actual frost dates vary year to year.

What should I plant next to Spinach?

Good companion plants for Spinach include Strawberries, Peas, Radish, Lettuce. 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.