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When to plant Lavender in Au Gres, MI

Plant Lavender in Au Gres, between June 2 and June 16 — the only viable window. Zone 5b's short season (147 frost-free days) rules out a fall crop.

When to Plant Lavender in Au Gres, MI

Lavender
Arenac County, Michigan Zone 5b July

July in the garden — Arenac County, Michigan

Each item below is timed to Arenac County, Michigan's frost dates and soil temperatures. Skip nothing, stress about nothing.

Avg. last frost May 12
Avg. first frost October 6
Soil temp (4") 78°F
Watering Moderate
Pest pressure High
Daylight 15 hrs
  1. Fire up the seed-starting tray: lavender

    These need a head start before your last frost (May 12). Sow into cells now so you're ready to transplant in a few weeks.

August prep starts now
  • First harvests: lavender

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Lavender (Lavandula angustifolia) is a fragrant Mediterranean sub-shrub prized for its silver-gray foliage and intensely aromatic purple flower spikes. A classic companion for roses and an unmatched pollinator magnet, lavender thrives in the exact conditions that challenge many plants: poor, rocky, alkaline soil with excellent drainage and full sun. English lavender is the most cold-hardy species, reliably perennial in Zones 5–9. Fresh or dried flowers are widely used in sachets, essential oils, culinary applications, and dried arrangements.

Au Gres, Michigan is in USDA Zone 5b. The average last spring frost is May 12 and the first fall frost is October 6, giving you a growing season of approximately 147 days.

At an elevation of 1,015 feet, Arenac County receives approximately 30.5 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86°F, providing good warmth for Lavender during the growing season.

Perennial Blooms in Summer Pollinator-friendly Deer-resistant Good for cutting Fragrant
Au Gres, MI (Zone 5b) Short season
147 days
Last Spring Frost May 12
147 growing days
First Fall Frost October 6

Au Gres Soil Profile

Soil Type

Silt Loam

Soil pH

6.2-7.1

Drainage

Well Drained

Lavender Planting Risk Windows

Early Start (70% safe) ✓ Fits season (7 days to spare)
Start indoors: Feb 25 Transplant: May 27 🌸 Bloom: Aug 5 – Sep 23
Recommended (50%) ✓ Fits season (7 days to spare)
Start indoors: Mar 3 Transplant: Jun 2 🌸 Bloom: Aug 11 – Sep 29
Safe Start (90%) ✓ Fits season (9 days to spare)
Start indoors: Mar 16 Transplant: Jun 15 🌸 Bloom: Aug 24 – Oct 12

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 Au Gres

How your county's soil matches Lavender's growing requirements.

Soil pH

Your soil pH (6.2–7.1) overlaps with Lavender's range (6.5–7.5), though not a perfect match.

Soil Texture

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

Drainage

Drainage is adequate for Lavender.

Organic Matter

Organic matter is excellent (4.6%) — Lavender will thrive.

How to Plant Lavender

0.5"
Planting Depth
18"
Between Plants
24"
Between Rows

Lavender Water Budget

Plant needs
0.3″/week
Rainfall provides
0.9″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft

Monthly Watering Guide for Lavender

Lavender needs approximately 0.3 inches of water per week (1.3" per month). Here's how your county's rainfall compares month by month.

Month Lavender Needs Rainfall You Supplement Action
Jan 1.4" 0" ❄️ Dormant
Feb 1.3" 0" ❄️ Dormant
Mar 2.2" 0" ❄️ Dormant
Apr 2.6" 0" ❄️ Dormant
May 1.3" 3.9" 0" ✅ Rainfall sufficient
Jun 1.3" 3.9" 0" ✅ Rainfall sufficient
Jul 1.3" 3.6" 0" ✅ Rainfall sufficient
Aug 1.3" 3.2" 0" ✅ Rainfall sufficient
Sep 1.3" 2.6" 0" ✅ Rainfall sufficient
Oct 1.3" 2.2" 0" ✅ Rainfall sufficient
Nov 2" 0" ❄️ Dormant
Dec 1.7" 0" ❄️ Dormant

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

Lavender 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.

Lavender needs ~1,522 GDD — county provides 2,131 GDD Excellent fit

Lavender Planting Timeline — Au Gres, MI

Lavender Planting Calendar

Activity When Date Range
Start Indoors March 3 Mar 3 – Mar 17
Transplant Outdoors June 2 Jun 2 – Jun 16
Bloom August 11 Aug 11 – Sep 29

Plant 0.5" deep · 18" apart · Rows 24" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.3"/week · Natural rainfall sufficient

📅 Days to Maturity

90–120 days

🧪 Soil pH

Needs 6.5–7.5 · Your soil: acceptable

🗺️ USDA Zone

Zone 5b

📆 Growing Season

147 days in Arenac County

Growing Tips for Lavender in Au Gres

Direct sow Lavender outdoors after May 12 in Arenac County when soil has warmed and frost danger has passed.

General growing tips

The single most important requirement for lavender success is excellent drainage — it will rot in heavy clay or wet winter soils before cold alone kills it. Amend with coarse sand or fine gravel if needed; raised beds work well in Zones 5–6. Start from rooted cuttings or transplants rather than seed for named cultivars. Transplant after last frost when soil is reliably warm (55°F+). Avoid rich or overly moist soils. Prune lightly after each flush of bloom, but never cut into old wood below the green growth zone — it will not regenerate from leafless woody stems. In Zones 5–6, mulch lightly with gravel (not bark/organic material which traps moisture) around the crown for winter protection. Year 2+ plants develop into full, mature shrubs with the most prolific bloom.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

When should I plant Lavender in Au Gres, MI?

In Au Gres, MI, plant Lavender after the last frost (around May 12) and before the first frost (around October 6). Best results when soil holds above 50°F.

What growing zone is Au Gres, MI for Lavender?

Au Gres sits in USDA Zone 5b. Lavender grows reliably in zones 5a through 9b, so it's a good fit here.

Can Lavender grow in Au Gres's climate?

Yes — Lavender grows well in Au Gres's temperate climate. Au Gres averages a 147-day frost-free season, with last frost around May 12 and first frost around October 6.

🌱

Your Arenac County Garden Planner — Free

A 22-page printable planner built for Arenac 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.

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