When to Plant Sweet Alyssum in USDA Zone 6b
Sweet Alyssum (Lobularia maritima) is a low-growing cool-season annual prized for its honey-scented clusters of tiny white, pink, or purple flowers. A workhorse border plant, it tolerates light frost, self-seeds readily, and attracts beneficial insects throughout its bloom season. In warm climates it often re-blooms in fall after summer heat fades.
In Zone 6b, the average last spring frost is around April 3 and the first fall frost is around October 25, giving you a growing season of approximately 205 days.
Sweet Alyssum Planting Timeline — Zone 6b
Where Is USDA Zone 6b?
The map below highlights the states that contain Zone 6b. Click any state to see the Sweet Alyssum planting schedule for that location.
Sweet Alyssum Planting Calendar — Zone 6b
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 20 | Feb 20 – Mar 6 |
| Transplant Outdoors | April 3 | Apr 3 – Apr 17 |
| Direct Sow | March 13 | Mar 13 – Apr 3 |
| Bloom | May 15 | May 15 – Jul 31 |
· 6" apart · Rows 8" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | Start Indoors Direct Sow |
| April | Transplant Outdoors Direct Sow |
| May | Bloom |
| June | Bloom |
| July | Bloom |
| August | — |
| September | — |
| October | — |
| November | — |
| December | — |
Free Zone 6b Planting Calendar PDF
Know exactly when to plant every crop in your zone. Get a printable month-by-month calendar customized for Zone 6b with start dates, transplant windows, and harvest times.
Growing Conditions
Sun
Full Sun (6-8+ hours)
💧 Water
Low — drought tolerant
Days to Maturity
45–60 days
Soil pH
6 – 7.5
Zone Temperature Range
-5°F to 0°F average annual minimum
Growing Season
205 days (Zone 6b average)
Planting Specifications
| Plant Spacing | 6 inches apart |
| Row Spacing | 8 inches between rows |
Succession Planting Sweet Alyssum in Zone 6b
Sow every 5.1 weeks for continuous harvest throughout the season.
Growing Tips for Sweet Alyssum in Zone 6b
Surface-sow seeds — they need light to germinate. Direct-sow as soon as soil can be worked in spring; in zones 7+ also sow in fall. Thin to 6 inches apart. Shear back hard in midsummer when heat causes dormancy — plants recover and re-bloom when cool weather returns. Self-seeds prolifically; allow a few plants to set seed for a perpetual colony.
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
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Saving Sweet Alyssum 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.
Sweet Alyssum in Other Zones
Sweet Alyssum 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 Alyssum in Zone 6b?
In Zone 6b, plan your Sweet Alyssum planting around the average last frost date of April 3. Start seeds indoors around February 20. Direct sow outdoors around March 13. Transplant seedlings around April 3.
Can Sweet Alyssum grow in Zone 6b?
Yes, Sweet Alyssum can grow well in Zone 6b, hardy in USDA zones 3a through 11b. Zone 6b has a growing season of approximately 205 days, which is sufficient for Sweet Alyssum (45-60 days to maturity).
When can I harvest Sweet Alyssum in Zone 6b?
In Zone 6b, expect to harvest Sweet Alyssum from May 15 – July 31. Sweet Alyssum takes 45-60 days from planting to harvest.
What is the last frost date for Zone 6b?
The average last spring frost in Zone 6b is around April 3, and the first fall frost is around October 25. This gives a growing season of approximately 205 days. These are 50% probability dates — actual frost dates vary year to year.
What should I plant next to Sweet Alyssum?
Good companion plants for Sweet Alyssum include Lettuce, Broccoli, Strawberries, Tomatoes. These companions can help with pest control, pollination, and nutrient sharing.
Your Zone 6b Garden Planner — Free
A 22-page printable planner tailored to Zone 6b. Planting dates, monthly task lists, harvest log, seed inventory, and succession charts — everything you need to plan a full season.