When to Plant Geraniums in USDA Zone 3a
Your June gardening checklist
We've pulled the most time-sensitive tasks for Zone 3a this June and put them front and centre. Tackle them in order.
Want it on paper? Download your Zone 3a planting guide →Geraniums (Pelargonium × hortorum) are tender perennials grown as warm-season annuals throughout North America. Prized for their bold flower clusters, long bloom period, and tolerance of summer heat when planted in well-drained soil, they anchor window boxes, containers, and bed borders from late spring until hard frost. Zones 9b–11b can overwinter plants in the ground.
In Zone 3a, the average last spring frost is around May 15 and the first fall frost is around September 15, giving you a growing season of approximately 123 days.
Geraniums Planting Timeline — Zone 3a
Where Is USDA Zone 3a?
The map below highlights the states that contain Zone 3a. Click any state to see the Geraniums planting schedule for that location.
Geraniums Planting Calendar — Zone 3a
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 20 | Feb 20 – Mar 6 |
| Transplant Outdoors | May 29 | May 29 – Jun 12 |
| Bloom | August 7 | Aug 7 – Oct 2 |
Plant 0.1" deep · 12" apart · Rows 14" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | Start Indoors |
| April | — |
| May | Transplant Outdoors |
| June | Transplant Outdoors |
| July | — |
| August | Bloom |
| September | Bloom |
| October | Bloom |
| November | — |
| December | — |
Free Zone 3a Planting Calendar PDF
Know exactly when to plant every crop in your zone. Get a printable month-by-month calendar customized for Zone 3a with start dates, transplant windows, and harvest times.
Growing Conditions
Sun
Full Sun (6-8+ hours)
💧 Water
Moderate — regular watering
Days to Maturity
70–100 days
Soil pH
6 – 7
Zone Temperature Range
-40°F to -35°F average annual minimum
Growing Season
123 days (Zone 3a average)
Planting Specifications
| Planting Depth | 0.1 inches |
| Plant Spacing | 12 inches apart |
| Row Spacing | 14 inches between rows |
Growing Tips for Geraniums in Zone 3a
Zone 3a has a short growing season (~123 days). Start Geraniums indoors early and use season-extension techniques like row covers and cold frames.
Start seeds indoors 10–12 weeks before last frost — germination is slow and erratic without bottom heat (70–75°F). Transplant after frost danger passes. Geraniums rarely direct-sown; cuttings or transplants are the standard. Deadhead spent umbels weekly to maintain continuous bloom. Let soil dry slightly between waterings to prevent root rot. In zones 10–11 plants may be left in ground year-round or overwintered as houseplants.
Companion Planting
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Saving Geraniums Seeds
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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
Geraniums in Other Zones
Geraniums 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 Geraniums in Zone 3a?
In Zone 3a, plan your Geraniums planting around the average last frost date of May 15. Start seeds indoors around February 20. Transplant seedlings around May 29.
Can Geraniums grow in Zone 3a?
Yes, Geraniums can grow well in Zone 3a, hardy in USDA zones 2a through 11b. Zone 3a has a growing season of approximately 123 days, which is sufficient for Geraniums (70-100 days to maturity).
When can I harvest Geraniums in Zone 3a?
In Zone 3a, expect to harvest Geraniums from August 7 – October 2. Geraniums takes 70-100 days from planting to harvest.
What is the last frost date for Zone 3a?
The average last spring frost in Zone 3a is around May 15, and the first fall frost is around September 15. This gives a growing season of approximately 123 days. These are 50% probability dates — actual frost dates vary year to year.
What should I plant next to Geraniums?
Good companion plants for Geraniums include Lobelia, Sweet Alyssum, Petunias, Bachelors Button. These companions can help with pest control, pollination, and nutrient sharing.
Your Zone 3a Garden Planner — Free
A 22-page printable planner tailored to Zone 3a. Planting dates, monthly task lists, harvest log, seed inventory, and succession charts — everything you need to plan a full season.