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When to Plant Salsify in Ontonagon County, MI

Ontonagon County, Michigan Zone 4a April

Your April gardening checklist

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

Avg. last frost May 22
Avg. first frost September 28
Soil temp (4") 41°F
Watering Low
Pest pressure Low
Daylight 13.3 hrs
Coming up in May — start thinking about
  • Direct-sowing: salsify

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Salsify is a root vegetable with a subtle oyster-like flavor, earning it the nickname "oyster plant." It produces long, slender, cream-colored roots.

Ontonagon County, Michigan is in USDA Zone 4a. The average last spring frost is May 22 and the first fall frost is September 28, giving you a growing season of approximately 129 days.

At an elevation of 502 feet, Ontonagon County receives approximately 42 inches of rainfall annually with predominantly silt loam soil. Summer highs average 80°F, so choose short-season varieties of Salsify to ensure they mature before fall.

Ontonagon County, MI (Zone 4a) Short season
129 days
Last Spring Frost May 22
129 growing days
First Fall Frost September 28
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Ontonagon County Soil Profile

Soil Type

Silt Loam

Soil pH

6.2-7.2

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Transplant: May 18 🍅 Harvest: Aug 31 – Oct 12
Recommended (50%) ✗ May not fit
Transplant: May 22 🍅 Harvest: Sep 4 – Oct 16
Safe Start (90%) ✗ May not fit
Transplant: Jun 6 🍅 Harvest: Sep 19 – Oct 31

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 Ontonagon County

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

Soil pH

Your soil pH (6.2–7.2) is within Salsify's preferred range (6.0–7.5).

Soil Texture

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

Organic Matter

Organic matter is excellent (5.1%) — Salsify will thrive.

How to Plant Salsify

0.5"
Planting Depth
6"
Between Plants
12"
Between Rows

Fall planting: Sow 12 weeks before your first frost date for a fall harvest.

Plant Water Budget

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

Monthly Watering Guide for Salsify

Salsify needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Salsify Needs Rainfall You Supplement Action
Jan 2" 0" ❄️ Dormant
Feb 2.1" 0" ❄️ Dormant
Mar 2.8" 0" ❄️ Dormant
Apr 4.4" 0" ❄️ Dormant
May 4.3" 4.8" 0" ✅ Rainfall sufficient
Jun 4.3" 5.2" 0" ✅ Rainfall sufficient
Jul 4.3" 4.3" 0" ✅ Rainfall sufficient
Aug 4.3" 4.2" 0.1" 💧 Light watering
Sep 4.3" 3.5" 0.8" 💧 Light watering
Oct 3.6" 0" ❄️ Dormant
Nov 2.6" 0" ❄️ Dormant
Dec 2.4" 0" ❄️ Dormant

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

Salsify 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.

Salsify needs ~1,150 GDD — county provides 1,290 GDD Good fit

Salsify Planting Timeline — Ontonagon County, MI

Salsify Planting Calendar

Activity When Date Range
Direct Sow May 15 May 15 – Jun 5
Harvest August 28 Aug 28 – Oct 9
Fall Sowing July 6 Jul 6 – Jul 20

Plant 0.5" deep · 6" apart · Rows 12" apart

Month-by-Month Timeline

MonthActivities
January
February
March
April
May Direct Sow
June Direct Sow
July Fall Sowing
August Harvest
September Harvest
October Harvest
November
December
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Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1"/week · Natural rainfall sufficient

📅 Days to Maturity

100–130 days

🧪 Soil pH

Needs 6–7.5 · Your soil: ideal

🗺️ USDA Zone

Zone 4a

📆 Growing Season

129 days in Ontonagon County

Growing Tips for Salsify in Ontonagon County

Direct sow Salsify outdoors after May 22 in Ontonagon County when soil has warmed and frost danger has passed.

Your 129.0-day growing season in Ontonagon County is tight for Salsify (100.0-130.0 days to maturity). Start indoors and choose early-maturing varieties.

Common pests for Salsify in this region include aphids and slugs. Use row covers early in the season and inspect plants weekly.

General growing tips

Direct sow in spring in deeply worked, stone-free soil. Use fresh seed only as viability drops quickly. Harvest in late fall after frost for best flavor.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Salsify in Ontonagon County, MI?

Ontonagon County is in Zone 4a with an average last frost of May 22. Plan your Salsify planting based on this frost date — see the calendar above for exact timing.

What planting zone is Ontonagon County, MI?

Ontonagon County, Michigan is in USDA Hardiness Zone 4a. The average last spring frost is May 22 and first fall frost is September 28.

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Your Ontonagon County Garden Planner — Free

A 24-page printable planner built for Ontonagon County (Zone 4a). 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 Ontonagon County, MI. Local conditions may vary. Last updated: April 2026.

Sources & credits

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