When to Plant Sweet Pea in USDA Zone 8b
Sweet peas (Lathyrus odoratus) are beloved cool-season climbing annuals grown primarily for their intensely fragrant, ruffled blooms in shades of pink, purple, red, and white. They thrive in cool spring conditions, climbing trellises to 4–6 feet, and make outstanding cut flowers. Bloom ceases once summer heat arrives, making early sowing critical for a long cutting season.
In Zone 8b, the average last spring frost is around February 25 and the first fall frost is around November 28, giving you a growing season of approximately 276 days.
Sweet Pea Planting Timeline — Zone 8b
Where Is USDA Zone 8b?
The map below highlights the states that contain Zone 8b. Click any state to see the Sweet Pea planting schedule for that location.
Sweet Pea Planting Calendar — Zone 8b
| Activity | When | Date Range |
|---|---|---|
| Bloom | December 5 | Dec 5 – Feb 13 |
| Fall Sowing | September 26 | Sep 26 – Oct 10 |
Plant 0.5" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | Bloom |
| February | Bloom |
| March | — |
| April | — |
| May | — |
| June | — |
| July | — |
| August | — |
| September | Fall Sowing |
| October | Fall Sowing |
| November | — |
| December | Bloom |
Free Zone 8b Planting Calendar PDF
Know exactly when to plant every crop in your zone. Get a printable month-by-month calendar customized for Zone 8b with start dates, transplant windows, and harvest times.
Growing Conditions
Sun
Full Sun (6-8+ hours)
💧 Water
Moderate — regular watering
Days to Maturity
65–85 days
Soil pH
7 – 7.5
Zone Temperature Range
15°F to 20°F average annual minimum
Growing Season
276 days (Zone 8b average)
Planting Specifications
| Planting Depth | 0.5 inches |
| Plant Spacing | 6 inches apart |
| Row Spacing | 12 inches between rows |
Succession Planting Sweet Pea in Zone 8b
Sow every 7.4 weeks for continuous harvest throughout the season.
Growing Tips for Sweet Pea in Zone 8b
Soak seeds 24 hours before sowing to soften the hard seed coat; nick the seed coat with a file for the fastest germination. In cold zones (2–6), direct-sow as soon as soil can be worked, 4–6 weeks before last frost; seedlings tolerate light frost but not a hard freeze. In zones 7–9, fall-sow 8–10 weeks before first frost for earlier, stronger spring bloom. Provide a trellis or netting from the start. Feed with low-nitrogen, high-potassium fertilizer once buds form. Pick blooms regularly — even one mature seed pod stops flower production. All plant parts are mildly toxic if eaten.
Companion Planting
Good Companions
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Saving Sweet Pea 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
Sweet Pea in Other Zones
Sweet Pea 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 Sweet Pea in Zone 8b?
In Zone 8b, plan your Sweet Pea planting around the average last frost date of February 25.
Can Sweet Pea grow in Zone 8b?
Yes, Sweet Pea can grow well in Zone 8b, hardy in USDA zones 2a through 9b. Zone 8b has a growing season of approximately 276 days, which is sufficient for Sweet Pea (65-85 days to maturity).
When can I harvest Sweet Pea in Zone 8b?
In Zone 8b, expect to harvest Sweet Pea from December 5 – February 13. Sweet Pea takes 65-85 days from planting to harvest.
What is the last frost date for Zone 8b?
The average last spring frost in Zone 8b is around February 25, and the first fall frost is around November 28. This gives a growing season of approximately 276 days. These are 50% probability dates — actual frost dates vary year to year.
What should I plant next to Sweet Pea?
Good companion plants for Sweet Pea include Larkspur, Foxglove, Snapdragon, Dianthus. These companions can help with pest control, pollination, and nutrient sharing.
Your Zone 8b Garden Planner — Free
A 22-page printable planner tailored to Zone 8b. Planting dates, monthly task lists, harvest log, seed inventory, and succession charts — everything you need to plan a full season.