When to Plant Larkspur in USDA Zone 9a
Larkspur (Consolida ajacis) is a cool-season annual that produces tall, delicate spires of blue, purple, pink, and white flowers reminiscent of its perennial cousin, delphinium. Direct-sown into cold soil or fall-sown in mild-winter climates, it blooms in spring before going to seed as summer heat arrives. An excellent cut flower and cottage-garden staple.
In Zone 9a, the average last spring frost is around February 10 and the first fall frost is around December 10, giving you a growing season of approximately 303 days.
Larkspur Planting Timeline — Zone 9a
Where Is USDA Zone 9a?
The map below highlights the states that contain Zone 9a. Click any state to see the Larkspur planting schedule for that location.
Larkspur Planting Calendar — Zone 9a
| Activity | When | Date Range |
|---|---|---|
| Bloom | December 10 | Dec 10 – Apr 1 |
| Fall Sowing | October 1 | Oct 1 – Oct 15 |
Plant 0.1" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | Bloom |
| February | Bloom |
| March | Bloom |
| April | Bloom |
| May | — |
| June | — |
| July | — |
| August | — |
| September | — |
| October | Fall Sowing |
| November | — |
| December | Bloom |
Free Zone 9a Planting Calendar PDF
Know exactly when to plant every crop in your zone. Get a printable month-by-month calendar customized for Zone 9a with start dates, transplant windows, and harvest times.
Growing Conditions
Sun
Full Sun (6-8+ hours)
💧 Water
Low — drought tolerant
Days to Maturity
60–90 days
Soil pH
6 – 7
Zone Temperature Range
20°F to 25°F average annual minimum
Growing Season
303 days (Zone 9a average)
Planting Specifications
| Planting Depth | 0.1 inches |
| Plant Spacing | 8 inches apart |
| Row Spacing | 12 inches between rows |
Succession Planting Larkspur in Zone 9a
Sow every 6.9 weeks for continuous harvest throughout the season.
Growing Tips for Larkspur in Zone 9a
Zone 9a offers a long growing season (~303 days). You can plant Larkspur earlier and may get multiple harvests.
Larkspur does not transplant well — direct-sow only. In cold climates (zones 2–6), sow directly in early spring as soon as soil can be worked, 4–6 weeks before last frost; cold soil improves germination. In zones 7–10, fall-sow 8–10 weeks before first frost for spring bloom. Press seeds lightly into soil; they need darkness to germinate — cover with 1/8–1/4 inch of soil. Thin to 6–12 inches to prevent powdery mildew. Allow seed pods to mature and self-sow for naturalized colonies. All parts are toxic if ingested.
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 Larkspur Seeds
Recommended for Your Garden
Reduce heat stress and sun scorch in hot climates with UV-stabilized shade cloth.
Start seeds indoors with reusable cell trays and humidity domes.
Test your soil pH, nitrogen, phosphorus, and potassium levels before planting.
Related Plants
Larkspur in Other Zones
Larkspur 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 Larkspur in Zone 9a?
In Zone 9a, plan your Larkspur planting around the average last frost date of February 10.
Can Larkspur grow in Zone 9a?
Yes, Larkspur can grow well in Zone 9a, hardy in USDA zones 2a through 10b. Zone 9a has a growing season of approximately 303 days, which is sufficient for Larkspur (60-90 days to maturity).
When can I harvest Larkspur in Zone 9a?
In Zone 9a, expect to harvest Larkspur from December 10 – April 1. Larkspur takes 60-90 days from planting to harvest.
What is the last frost date for Zone 9a?
The average last spring frost in Zone 9a is around February 10, and the first fall frost is around December 10. This gives a growing season of approximately 303 days. These are 50% probability dates — actual frost dates vary year to year.
What should I plant next to Larkspur?
Good companion plants for Larkspur include Roses, Peonies, Foxglove, Sweet Pea. These companions can help with pest control, pollination, and nutrient sharing.
Your Zone 9a Garden Planner — Free
A 22-page printable planner tailored to Zone 9a. Planting dates, monthly task lists, harvest log, seed inventory, and succession charts — everything you need to plan a full season.