When to Plant Sweet Alyssum in USDA Zone 5b
What to do in June
Each item below is timed to Zone 5b's frost dates and soil temperatures. Skip nothing, stress about nothing.
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Indoor seed-starting week for sweet alyssum
Starting these indoors now means sturdy transplants ready the moment your soil warms up.
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Pick sweet alyssum
Taste as you pick. The first ripe produce is the best feedback loop you'll get all season.
July will be here before you know it — start on
- First harvests: sweet alyssum
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 5b, the average last spring frost is around April 18 and the first fall frost is around October 13, giving you a growing season of approximately 178 days.
Sweet Alyssum Planting Timeline — Zone 5b
Where Is USDA Zone 5b?
The map below highlights the states that contain Zone 5b. Click any state to see the Sweet Alyssum planting schedule for that location.
Sweet Alyssum Planting Calendar — Zone 5b
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 28 | Feb 28 – Mar 14 |
| Transplant Outdoors | April 18 | Apr 18 – May 2 |
| Direct Sow | April 4 | Apr 4 – Apr 25 |
| Bloom | May 30 | May 30 – Aug 8 |
· 6" apart · Rows 8" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | Start Indoors |
| April | Transplant Outdoors Direct Sow |
| May | Transplant Outdoors Bloom |
| June | Bloom |
| July | Bloom |
| August | Bloom |
| September | — |
| October | — |
| November | — |
| December | — |
Free Zone 5b Planting Calendar PDF
Know exactly when to plant every crop in your zone. Get a printable month-by-month calendar customized for Zone 5b 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
-15°F to -10°F average annual minimum
Growing Season
178 days (Zone 5b average)
Planting Specifications
| Plant Spacing | 6 inches apart |
| Row Spacing | 8 inches between rows |
Succession Planting Sweet Alyssum in Zone 5b
Sow every 5.1 weeks for continuous harvest throughout the season.
Growing Tips for Sweet Alyssum in Zone 5b
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
- Full seed-starting + planting schedule with timing and spacing
- Bonus: square-foot gardening guide + printable seasonal planners
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.
Related Plants
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 5b?
In Zone 5b, plan your Sweet Alyssum planting around the average last frost date of April 18. Start seeds indoors around February 28. Direct sow outdoors around April 4. Transplant seedlings around April 18.
Can Sweet Alyssum grow in Zone 5b?
Yes, Sweet Alyssum can grow well in Zone 5b, hardy in USDA zones 3a through 11b. Zone 5b has a growing season of approximately 178 days, which is sufficient for Sweet Alyssum (45-60 days to maturity).
When can I harvest Sweet Alyssum in Zone 5b?
In Zone 5b, expect to harvest Sweet Alyssum from May 30 – August 8. Sweet Alyssum takes 45-60 days from planting to harvest.
What is the last frost date for Zone 5b?
The average last spring frost in Zone 5b is around April 18, and the first fall frost is around October 13. This gives a growing season of approximately 178 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 5b Garden Planner — Free
A 22-page printable planner tailored to Zone 5b. Planting dates, monthly task lists, harvest log, seed inventory, and succession charts — everything you need to plan a full season.