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When to Plant Mulberries in Iron County, MO

Iron County, Missouri Zone 6b May

Your May gardening checklist

Welcome to May in Zone 6b. These are the moves that will have the biggest impact on your growing season.

Avg. last frost April 16
Avg. first frost October 21
Soil temp (4") 63°F
Watering Low
Pest pressure Low
Daylight 14 hrs
  1. Transplant mulberries outside

    Pinch off the lowest leaves on each seedling before you plant — it reduces water loss while the roots catch up.

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Mulberries are fast-growing, long-lived trees that produce abundant sweet-tart berries over an extended harvest period. The berries resemble elongated blackberries.

Iron County, Missouri is in USDA Zone 6b. The average last spring frost is April 16 and the first fall frost is October 21, giving you a growing season of approximately 188 days.

At an elevation of 1,227 feet, Iron County receives approximately 35.1 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86°F, providing good warmth for Mulberries during the growing season.

Iron County, MO (Zone 6b) Moderate season
188 days
Last Spring Frost April 16
188 growing days
First Fall Frost October 21

Iron County Soil Profile

Soil Type

Silt Loam

Soil pH

5.6-6.7

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season
Transplant: Apr 29
Recommended (50%) ✓ Fits season
Transplant: May 7
Safe Start (90%) ✓ Fits season
Transplant: May 20

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 Iron County

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

Soil pH

Your soil pH (5.6–6.7) is within Mulberries's preferred range (5.5–7.0).

Soil Texture

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

Drainage

Drainage is adequate for Mulberries.

Organic Matter

Organic matter is moderate (3.1%). Annual compost additions will help Mulberries.

How to Plant Mulberries

120"
Between Plants
144"
Between Rows

Plant Water Budget

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

Monthly Watering Guide for Mulberries

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

Month Mulberries Needs Rainfall You Supplement Action
Jan 1.5" 0" ❄️ Dormant
Feb 1.5" 0" ❄️ Dormant
Mar 2.3" 0" ❄️ Dormant
Apr 4.3" 3.7" 0.6" 💧 Light watering
May 4.3" 4" 0.3" 💧 Light watering
Jun 4.3" 4" 0.3" 💧 Light watering
Jul 4.3" 3.4" 0.9" 💧 Light watering
Aug 4.3" 4.1" 0.2" 💧 Light watering
Sep 4.3" 2.8" 1.5" 💧 Light watering
Oct 4.3" 3.1" 1.2" 💧 Light watering
Nov 2.5" 0" ❄️ Dormant
Dec 2.2" 0" ❄️ Dormant

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

Mulberries 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.

Mulberries needs ~18,524 GDD — county provides 2,726 GDD May not mature

Mulberries Planting Timeline — Iron County, MO

Mulberries Planting Calendar

Activity When Date Range
Transplant Outdoors May 7 May 7 – May 21

· 120" apart · Rows 144" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1"/week · Natural rainfall sufficient

📅 Days to Maturity

730–1825 days

🧪 Soil pH

Needs 5.5–7 · Your soil: ideal

🗺️ USDA Zone

Zone 6b

📆 Growing Season

188 days in Iron County

Growing Tips for Mulberries in Iron County

Direct sow Mulberries outdoors after April 16 in Iron County when soil has warmed and frost danger has passed.

Your 188.0-day growing season in Iron County is tight for Mulberries (730.0-1825.0 days to maturity). Start indoors and choose early-maturing varieties.

General growing tips

Plant away from driveways and patios as fallen berries stain. Minimal pruning is needed. Harvest by shaking branches over a tarp. Birds love mulberries so plant extra.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Mulberries in Iron County, MO?

Iron County is in Zone 6b with an average last frost of April 16. Plan your Mulberries planting based on this frost date — see the calendar above for exact timing.

What planting zone is Iron County, MO?

Iron County, Missouri is in USDA Hardiness Zone 6b. The average last spring frost is April 16 and first fall frost is October 21.

🌱

Your Iron County Garden Planner — Free

A 24-page printable planner built for Iron County (Zone 6b). 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 Iron County, MO. Local conditions may vary. Last updated: May 2026.

Sources & credits

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