When to Plant Coreopsis in USDA Zone 5a
This month in Zone 5a
June rewards gardeners who work with the weather, not against it. Here's how to stay in step this month in Zone 5a.
July prep starts now
- Starting indoors: coreopsis
- First harvests: coreopsis
Coreopsis (Tickseed) is a cheerful, long-blooming native perennial that produces a continuous flush of bright yellow, gold, or bi-colored daisy-like flowers from early summer well into fall. One of the most reliable cut-and-come-again bloomers in the perennial garden, it thrives in hot, dry, sunny conditions and poor soil where many competitors struggle. An invaluable nectar source for native bees and butterflies, and a butterfly host plant for several species.
In Zone 5a, the average last spring frost is around April 25 and the first fall frost is around October 8, giving you a growing season of approximately 166 days.
Coreopsis Planting Timeline — Zone 5a
Where Is USDA Zone 5a?
The map below highlights the states that contain Zone 5a. Click any state to see the Coreopsis planting schedule for that location.
Coreopsis Planting Calendar — Zone 5a
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 21 | Feb 21 – Mar 7 |
| Transplant Outdoors | May 9 | May 9 – May 23 |
| Direct Sow | May 2 | May 2 – May 23 |
| Bloom | July 18 | Jul 18 – Oct 24 |
Plant 0.1" deep · 18" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | Start Indoors |
| April | — |
| May | Transplant Outdoors Direct Sow |
| June | — |
| July | Bloom |
| August | Bloom |
| September | Bloom |
| October | Bloom |
| November | — |
| December | — |
Free Zone 5a Planting Calendar PDF
Know exactly when to plant every crop in your zone. Get a printable month-by-month calendar customized for Zone 5a with start dates, transplant windows, and harvest times.
Growing Conditions
Sun
Full Sun (6-8+ hours)
💧 Water
Low — drought tolerant
Days to Maturity
60–80 days
Soil pH
5.5 – 7.5
Zone Temperature Range
-20°F to -15°F average annual minimum
Growing Season
166 days (Zone 5a average)
Planting Specifications
| Planting Depth | 0.1 inches |
| Plant Spacing | 18 inches apart |
| Row Spacing | 24 inches between rows |
Succession Planting Coreopsis in Zone 5a
Sow every 6.9 weeks for continuous harvest throughout the season.
Growing Tips for Coreopsis in Zone 5a
Start seeds indoors 8–10 weeks before last frost or direct sow after last frost. Seeds germinate easily without stratification. Thrives in poor to average, well-drained soil — rich soil promotes foliage over flowers. Drought tolerant once established; overwatering is the most common mistake. Deadhead spent blooms to maintain continuous flowering through the season. Shear plants by one-third in midsummer for a fresh flush of late-season blooms. Year 2+ plants bloom most heavily. Divide every 2–3 years in early spring to rejuvenate crowded clumps.
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 Coreopsis Seeds
Recommended for Your Garden
Start seeds indoors with reusable cell trays and humidity domes.
Test your soil pH, nitrogen, phosphorus, and potassium levels before planting.
Keep your garden organized with durable, weather-resistant plant labels.
Related Plants
Coreopsis in Other Zones
Coreopsis 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 Coreopsis in Zone 5a?
In Zone 5a, plan your Coreopsis planting around the average last frost date of April 25. Start seeds indoors around February 21. Direct sow outdoors around May 2. Transplant seedlings around May 9.
Can Coreopsis grow in Zone 5a?
Yes, Coreopsis can grow well in Zone 5a, hardy in USDA zones 3a through 9b. Zone 5a has a growing season of approximately 166 days, which is sufficient for Coreopsis (60-80 days to maturity).
When can I harvest Coreopsis in Zone 5a?
In Zone 5a, expect to harvest Coreopsis from July 18 – October 24. Coreopsis takes 60-80 days from planting to harvest.
What is the last frost date for Zone 5a?
The average last spring frost in Zone 5a is around April 25, and the first fall frost is around October 8. This gives a growing season of approximately 166 days. These are 50% probability dates — actual frost dates vary year to year.
What should I plant next to Coreopsis?
Good companion plants for Coreopsis include Echinacea, Black Eyed Susan, Yarrow, Salvia. These companions can help with pest control, pollination, and nutrient sharing.
Your Zone 5a Garden Planner — Free
A 22-page printable planner tailored to Zone 5a. Planting dates, monthly task lists, harvest log, seed inventory, and succession charts — everything you need to plan a full season.