Blog

When to plant Sweet Alyssum in Lake County County,

Plant Sweet Alyssum in Lake County County during the brief April 30–May 21 window. With 145 frost-free days, fall plantings can't mature before October 6.

When to Plant Sweet Alyssum in Lake County, MI

Lake County, Michigan Zone 5b June

Top priorities for Lake County, Michigan gardeners in June

Your garden in Lake County, Michigan is working on a schedule, even when you're not. Here's where you should be this June.

Avg. last frost May 14
Avg. first frost October 6
Soil temp (4") 67°F
Watering Moderate
Pest pressure High
Daylight 15.3 hrs
  1. It's harvest week for 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
  • Starting indoors: sweet alyssum
  • First harvests: sweet alyssum

Instant PDF download. No spam, unsubscribe any time.

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.

Lake County, Michigan is in USDA Zone 5b. The average last spring frost is May 14 and the first fall frost is October 6, giving you a growing season of approximately 145 days.

At an elevation of 733 feet, Lake County receives approximately 33.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86°F, providing good warmth for Sweet Alyssum during the growing season.

Annual Blooms in Spring Pollinator-friendly Deer-resistant Fragrant
Lake County, MI (Zone 5b) Short season
145 days
Last Spring Frost May 14
145 growing days
First Fall Frost October 6

Lake County Soil Profile

Soil Type

Silt Loam

Soil pH

6.2-7.1

Drainage

Well Drained

Sweet Alyssum Planting Risk Windows

Early Start (70% safe) ✓ Fits season (34 days to spare)
Start indoors: Mar 20 Transplant: May 8 🌸 Bloom: Jun 19 – Aug 28
Recommended (50%) ✓ Fits season (33 days to spare)
Start indoors: Mar 26 Transplant: May 14 🌸 Bloom: Jun 25 – Sep 3
Safe Start (90%) ✓ Fits season (38 days to spare)
Start indoors: Apr 7 Transplant: May 26 🌸 Bloom: Jul 7 – Sep 15

Percentages indicate frost risk at transplant. The 70% safe window means there is a 30% chance of frost after transplant — suitable for cold-hardy crops or gardeners with frost protection. The 90% safe window is best for tender plants.

Soil Compatibility in Lake County

How your county's soil matches Sweet Alyssum's growing requirements.

Soil pH

Your soil pH (6.2–7.1) is within Sweet Alyssum's preferred range (6.0–7.5).

Soil Texture

The silt loam soil in Lake County is excellent for Sweet Alyssum — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is excellent (4.9%) — Sweet Alyssum will thrive.

How to Plant Sweet Alyssum

6"
Between Plants
8"
Between Rows

Succession Planting Sweet Alyssum

3
successive plantings in your 145-day season

Sow every 5.1 weeks. Last sowing by Aug 07 to harvest before frost.

Sweet Alyssum Water Budget

Plant needs
0.5″/week
Rainfall provides
1.0″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft
Drought risk

Water stress score is 6/10 — consider drought-tolerant varieties and mulching

Monthly Watering Guide for Sweet Alyssum

Sweet Alyssum needs approximately 0.5 inches of water per week (2.2" per month). Here's how your county's rainfall compares month by month.

Month Sweet Alyssum Needs Rainfall You Supplement Action
Jan 1.5" 0" ❄️ Dormant
Feb 1.5" 0" ❄️ Dormant
Mar 2.1" 0" ❄️ Dormant
Apr 3.7" 0" ❄️ Dormant
May 2.2" 4.3" 0" ✅ Rainfall sufficient
Jun 2.2" 3.7" 0" ✅ Rainfall sufficient
Jul 2.2" 3.9" 0" ✅ Rainfall sufficient
Aug 2.2" 3.2" 0" ✅ Rainfall sufficient
Sep 2.2" 3.3" 0" ✅ Rainfall sufficient
Oct 2.2" 2.8" 0" ✅ Rainfall sufficient
Nov 2" 0" ❄️ Dormant
Dec 1.6" 0" ❄️ Dormant

Water needs are for active growing months only (May–Oct in Lake County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Sweet Alyssum Heat Requirements (GDD)

What are Growing Degree Days (GDD)?

Growing Degree Days measure the total warmth your plants receive during the growing season. Think of it as a "heat bank" — every day above 50°F deposits warmth that helps your plants grow.

Each plant needs a certain amount of accumulated heat to mature. If your county provides more GDD than the plant needs, it's a great fit. If it's close, you may want to choose faster-maturing varieties or start seeds indoors to get a head start.

Sweet Alyssum needs ~761 GDD — county provides 2,102 GDD Excellent fit

Sweet Alyssum Planting Timeline — Lake County, MI

Sweet Alyssum Planting Calendar

Activity When Date Range
Start Indoors March 26 Mar 26 – Apr 9
Transplant Outdoors May 14 May 14 – May 28
Direct Sow April 30 Apr 30 – May 21
Bloom June 25 Jun 25 – Sep 3

· 6" apart · Rows 8" apart

Month-by-Month Timeline

MonthActivities
January
February
March Start Indoors
April Start Indoors Direct Sow
May Transplant Outdoors Direct Sow
June Bloom
July Bloom
August Bloom
September Bloom
October
November
December

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.5"/week · Natural rainfall sufficient

📅 Days to Maturity

45–60 days

🧪 Soil pH

Needs 6–7.5 · Your soil: ideal

🗺️ USDA Zone

Zone 5b

📆 Growing Season

145 days in Lake County

Growing Tips for Sweet Alyssum in Lake County

Direct sow Sweet Alyssum outdoors after May 14 in Lake County when soil has warmed and frost danger has passed.

Common pests for Sweet Alyssum in this region include cabbage worm and flea beetles. Use row covers early in the season and inspect plants weekly.

General growing tips

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

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Sweet Alyssum in Lake County, MI?

Lake County is in Zone 5b with an average last frost of May 14. Plan your Sweet Alyssum planting based on this frost date — see the calendar above for exact timing.

What planting zone is Lake County, MI?

Lake County, Michigan is in USDA Hardiness Zone 5b. The average last spring frost is May 14 and first fall frost is October 6.

When should I plant Sweet Alyssum in Lake County County, ?

In Lake County County, , plant Sweet Alyssum after the last frost (around May 14) and before the first frost (around October 6). Best results when soil holds above 50°F.

What growing zone is Lake County County, for Sweet Alyssum?

Lake County County sits in USDA Zone 5b. Sweet Alyssum grows reliably in zones 3a through 11b, so it's a good fit here.

Can Sweet Alyssum grow in Lake County County's climate?

Yes — Sweet Alyssum grows well in Lake County County's temperate climate. Lake County County averages a 145-day frost-free season, with last frost around May 14 and first frost around October 6.

🌱

Your Lake County Garden Planner — Free

A 22-page printable planner built for Lake County (Zone 5b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

Instant PDF download. No spam, unsubscribe any time.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Lake County, MI. Local conditions may vary. Last updated: June 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.