When to Plant Snapdragon in USDA Zone 4a
June in Zone 4a — your action list
We've pulled the most time-sensitive tasks for Zone 4a this June and put them front and centre. Tackle them in order.
July prep starts now
- Starting indoors: snapdragon
- First harvests: snapdragon
Snapdragons (Antirrhinum majus) are classic cool-season annuals whose upright spikes of dragon-lipped flowers are among spring's most dramatic displays. Tolerating light frosts, they bloom from early spring until summer heat shuts them down — then often revive in fall. In zones 9-11 they are grown as fall-planted winter annuals and may re-seed to naturalize.
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.
Snapdragon 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 Snapdragon planting schedule for that location.
Snapdragon Planting Calendar — Zone 4a
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 18 | Feb 18 – Mar 4 |
| Transplant Outdoors | May 6 | May 6 – May 20 |
| Bloom | July 15 | Jul 15 – Sep 9 |
· 9" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | Start Indoors |
| April | — |
| May | Transplant Outdoors |
| June | — |
| July | Bloom |
| August | Bloom |
| September | Bloom |
| 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
Moderate — regular watering
Days to Maturity
70–100 days
Soil pH
6.2 – 7
Zone Temperature Range
-30°F to -25°F average annual minimum
Growing Season
145 days (Zone 4a average)
Planting Specifications
| Plant Spacing | 9 inches apart |
| Row Spacing | 12 inches between rows |
Succession Planting Snapdragon in Zone 4a
Sow every 8 weeks for continuous harvest throughout the season.
Growing Tips for Snapdragon in Zone 4a
Zone 4a has a short growing season (~145 days). Start Snapdragon indoors early and use season-extension techniques like row covers and cold frames.
Start indoors 10-12 weeks before last frost; seeds need light to germinate — press into moist medium and do not cover. Transplant after hardening off, even if light frosts remain. Pinch seedlings once to encourage branching. Deadhead to prolong blooming. In zones 8-11, sow in fall for a winter-to-spring show. Tall varieties (24-36") make excellent cut flowers.
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 Snapdragon 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
Snapdragon in Other Zones
Snapdragon 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 Snapdragon in Zone 4a?
In Zone 4a, plan your Snapdragon planting around the average last frost date of May 6. Start seeds indoors around February 18. Transplant seedlings around May 6.
Can Snapdragon grow in Zone 4a?
Yes, Snapdragon can grow well in Zone 4a, hardy in USDA zones 2a through 11b. Zone 4a has a growing season of approximately 145 days, which is sufficient for Snapdragon (70-100 days to maturity).
When can I harvest Snapdragon in Zone 4a?
In Zone 4a, expect to harvest Snapdragon from July 15 – September 9. Snapdragon takes 70-100 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 Snapdragon?
Good companion plants for Snapdragon include Lettuce, Carrots, Sweet Alyssum, Lobelia. These companions can help with pest control, pollination, and nutrient sharing.
Your Zone 4a Garden Planner — Free
A 22-page printable planner tailored to Zone 4a. Planting dates, monthly task lists, harvest log, seed inventory, and succession charts — everything you need to plan a full season.