When to Plant Thyme in USDA Zone 4a
This month in Zone 4a
Your Zone 4a garden is entering a new phase. Here's what's on the schedule for April and why each task matters now.
A few tasks this April that'll pay off in May
- Transplants going out: thyme
Thyme is a low-growing perennial herb with tiny, aromatic leaves and a warm, earthy flavor. It is one of the most versatile culinary and medicinal herbs.
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.
Thyme 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 Thyme planting schedule for that location.
Thyme Planting Calendar — Zone 4a
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | May 13 | May 13 – May 27 |
| Harvest | July 22 | Jul 22 – Sep 23 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | — |
| May | Transplant Outdoors |
| June | — |
| July | Harvest |
| August | Harvest |
| September | Harvest |
| 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.
Growing Conditions
Sun
Full Sun (6-8+ hours)
💧 Water
0.3"/week · Low — drought tolerant
Days to Maturity
70–90 days
Soil pH
6 – 8
Zone Temperature Range
°F to °F average annual minimum
Growing Season
145 days (Zone average)
Planting Specifications
| Planting Depth | 0.5 inches |
| Plant Spacing | 8 inches apart |
| Row Spacing | 12 inches between rows |
Succession Planting Thyme in Zone
Sow every 8 weeks for continuous harvest throughout the season.
Growing Tips for Thyme in Zone
Zone has a short growing season (~145 days). Start Thyme indoors early and use season-extension techniques like row covers and cold frames.
Start from seed, cuttings, or divisions. Plant in well-drained, lean soil. Prune lightly after flowering. Replace plants every 3-4 years when they become woody.
Companion Planting
Good Companions
The Gardener's Encyclopedia to Companion Planting
The pairings that make vegetables, herbs, and flowers grow better — and the ones that quietly wreck a bed.
- Proven pairings for 200+ vegetables, herbs, flowers, and fruits
- Full seed-starting + planting schedule with timing and spacing
- Bonus: square-foot gardening guide + printable seasonal planners
Saving Thyme Seeds
Recommended for Your Garden
Breathable fabric pots that promote healthy root growth and prevent overwatering.
Built-in reservoir keeps herbs and greens consistently watered with less effort.
Start seeds indoors with reusable cell trays and humidity domes.
Related Plants
Thyme in Other Zones
Thyme by State
- Alabama
- Alaska
- Arizona
- Arkansas
- California
- Colorado
- Connecticut
- Delaware
- Florida
- Georgia
- Hawaii
- Idaho
- Illinois
- Indiana
- Iowa
- Kansas
- Kentucky
- Louisiana
- Maine
- Maryland
- Massachusetts
- Michigan
- Minnesota
- Mississippi
- Missouri
- Montana
- Nebraska
- Nevada
- New Hampshire
- New Jersey
- New Mexico
- New York
- North Carolina
- North Dakota
- Ohio
- Oklahoma
- Oregon
- Pennsylvania
- Rhode Island
- South Carolina
- South Dakota
- Tennessee
- Texas
- Utah
- Vermont
- Virginia
- Washington
- West Virginia
- Wisconsin
- Wyoming
Frequently Asked Questions
When should I plant Thyme in Zone 4a?
In Zone 4a, plan your Thyme planting around the average last frost date of May 6. Transplant seedlings around May 13.
Can Thyme grow in Zone 4a?
Yes, Thyme can grow well in Zone 4a, hardy in USDA zones 4a through 9b. Zone 4a has a growing season of approximately 145 days, which is sufficient for Thyme (70-90 days to maturity).
When can I harvest Thyme in Zone 4a?
In Zone 4a, expect to harvest Thyme from July 22 – September 23. Thyme takes 70-90 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 Thyme?
Good companion plants for Thyme include Tomatoes, Eggplant, Rosemary, Cabbage. 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.