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When to Plant Rosemary in USDA Zone 10b

Zone 10b Zone 10b April

This month in Zone 10b

We've pulled the most time-sensitive tasks for Zone 10b this April and put them front and centre. Tackle them in order.

Avg. last frost February 23
Avg. first frost November 1
May prep starts now
  • First harvests: rosemary
Get the full Zone 10b Garden Planner — free →
Rosemary

Rosemary is an aromatic evergreen shrub with needle-like leaves and a piney, citrus flavor. It is a Mediterranean herb that thrives in warm, dry conditions.

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

Rosemary 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 Rosemary planting schedule for that location.

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

Rosemary Planting Calendar — Zone 10b

Activity When Date Range
Transplant Outdoors January 8 Jan 8 – Jan 22
Harvest April 2 Apr 2 – Aug 20

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

Month-by-Month Timeline

MonthActivities
January Transplant Outdoors
February
March
April Harvest
May Harvest
June Harvest
July Harvest
August Harvest
September
October
November
December

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

Full Sun (6-8+ hours)

💧 Water

0.3"/week · Low — drought tolerant

Days to Maturity

80–180 days

Soil pH

6 – 7.5

Zone Temperature Range

°F to °F average annual minimum

Growing Season

364 days (Zone average)

Planting Specifications

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

Succession Planting Rosemary in Zone

5
successive plantings in Zone 's ~364-day season

Sow every 9.1 weeks for continuous harvest throughout the season.

Growing Tips for Rosemary in Zone

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

Grow in well-drained soil and avoid overwatering. In cold climates, grow in containers and bring indoors for winter. Propagate from stem cuttings for faster results than seed.

Companion Planting

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Saving Rosemary Seeds

Recommended for Your Garden

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Fabric Grow Bags $10-25

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

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Self-Watering Planters $15-40

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 Rosemary in Zone 10b?

In Zone 10b, plan your Rosemary planting around the average last frost date of January 1. Transplant seedlings around January 8.

Can Rosemary grow in Zone 10b?

Yes, Rosemary can grow well in Zone 10b, hardy in USDA zones 7a through 10b. Zone 10b has a growing season of approximately 364 days, which is sufficient for Rosemary (80-180 days to maturity).

When can I harvest Rosemary in Zone 10b?

In Zone 10b, expect to harvest Rosemary from April 2 – August 20. Rosemary takes 80-180 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 Rosemary?

Good companion plants for Rosemary include Sage, Thyme, Lavender, Carrots. 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: April 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.