When to Plant Yarrow in USDA Zone 4b
Yarrow is a drought-tolerant perennial herb with feathery foliage and flat-topped flower clusters in white, yellow, pink, or red. It attracts beneficial insects and is used in herbal medicine.
In Zone 4b, the average last spring frost is around May 1 and the first fall frost is around October 3, giving you a growing season of approximately 155 days.
Yarrow Planting Timeline — Zone 4b
Where Is USDA Zone 4b?
The map below highlights the states that contain Zone 4b. Click any state to see the Yarrow planting schedule for that location.
Yarrow Planting Calendar — Zone 4b
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | May 8 | May 8 – May 22 |
| Harvest | August 7 | Aug 7 – Oct 2 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | — |
| May | Transplant Outdoors |
| June | — |
| July | — |
| August | Harvest |
| September | Harvest |
| October | Harvest |
| November | — |
| December | — |
Free Zone 4b Planting Calendar PDF
Know exactly when to plant every crop in your zone. Get a printable month-by-month calendar customized for Zone 4b with start dates, transplant windows, and harvest times.
Growing Conditions
Sun
Full Sun (6-8+ hours)
💧 Water
Low — drought tolerant
Days to Maturity
90–120 days
Soil pH
5.5 – 7
Zone Temperature Range
-25°F to -20°F average annual minimum
Growing Season
155 days (Zone 4b average)
Planting Specifications
| Planting Depth | 0.5 inches |
| Plant Spacing | 8 inches apart |
| Row Spacing | 12 inches between rows |
Growing Tips for Yarrow in Zone 4b
Zone 4b has a short growing season (~155 days). Start Yarrow indoors early and use season-extension techniques like row covers and cold frames.
Direct sow or start from divisions. Yarrow thrives in poor soil and is very drought-tolerant. Deadhead to encourage reblooming. Divide clumps every 3 years.
Companion Planting
Good Companions
Level Up Your Garden
Saving Yarrow Seeds
Recommended for Your Garden
Full-spectrum LED lights for starting seeds indoors when daylight is limited.
Warm soil for faster germination of heat-loving crops like tomatoes and peppers.
Protect plants from frost, wind, and pests while letting light and water through.
Related Plants
Yarrow in Other Zones
Yarrow 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 Yarrow in Zone 4b?
In Zone 4b, plan your Yarrow planting around the average last frost date of May 1. Transplant seedlings around May 8.
Can Yarrow grow in Zone 4b?
Yes, Yarrow can grow well in Zone 4b, hardy in USDA zones 3a through 9b. Zone 4b has a growing season of approximately 155 days, which is sufficient for Yarrow (90-120 days to maturity).
When can I harvest Yarrow in Zone 4b?
In Zone 4b, expect to harvest Yarrow from August 7 – October 2. Yarrow takes 90-120 days from planting to harvest.
What is the last frost date for Zone 4b?
The average last spring frost in Zone 4b is around May 1, and the first fall frost is around October 3. This gives a growing season of approximately 155 days. These are 50% probability dates — actual frost dates vary year to year.
What should I plant next to Yarrow?
Good companion plants for Yarrow include Lavender, Rosemary, Thyme. These companions can help with pest control, pollination, and nutrient sharing.
Plan Your Garden with Confidence
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