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When to plant Mulberries in Custer County County,

Custer County County's short 79-day growing season means one Mulberries planting between July 9 and July 23. No fall crop in Zone 5b.

When to Plant Mulberries in Custer County, ID

Custer County, Idaho Zone 5b June

Top priorities for Custer County, Idaho gardeners in June

June is a pivotal month for Custer County, Idaho gardens. Focus on these tasks first and you'll set up the rest of the season for success.

Avg. last frost June 18
Avg. first frost September 5
Soil temp (4") 51°F
Watering High
Pest pressure High
Daylight 15.3 hrs
A few tasks this June that'll pay off in July
  • Transplants going out: mulberries

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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.

Custer County, Idaho is in USDA Zone 5b. The average last spring frost is June 18 and the first fall frost is September 5, giving you a growing season of approximately 79 days.

At an elevation of 5,189 feet, Custer County receives approximately 20.6 inches of rainfall annually with predominantly loam soil. Summer highs average 80°F, so choose short-season varieties of Mulberries to ensure they mature before fall.

Custer County, ID (Zone 5b) Very short season
79 days
Last Spring Frost June 18
79 growing days
First Fall Frost September 5

Custer County Soil Profile

Soil Type

Loam

Soil pH

6.3-8

Drainage

Well Drained

Mulberries Planting Risk Windows

Early Start (70% safe) ✓ Fits season
Transplant: Jul 2
Recommended (50%) ✓ Fits season
Transplant: Jul 9
Safe Start (90%) ✓ Fits season
Transplant: Jul 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 Custer County

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

Soil pH

Your soil pH (6.3–8.0) is more alkaline than Mulberries prefers (5.5–7.0). Add sulfur or peat moss to lower pH.

Soil Texture

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

Organic Matter

Organic matter is moderate (2.3%). Annual compost additions will help Mulberries.

How to Plant Mulberries

120"
Between Plants
144"
Between Rows

Mulberries Water Budget

Plant needs
1.0″/week
Rainfall provides
1.1″/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 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 1.3" 0" ❄️ Dormant
Feb 1.3" 0" ❄️ Dormant
Mar 1.7" 0" ❄️ Dormant
Apr 2.4" 0" ❄️ Dormant
May 2.3" 0" ❄️ Dormant
Jun 4.3" 1.5" 2.8" 🚿 Regular watering
Jul 4.3" 2" 2.3" 🚿 Regular watering
Aug 4.3" 2.1" 2.2" 🚿 Regular watering
Sep 4.3" 1.7" 2.6" 🚿 Regular watering
Oct 1.6" 0" ❄️ Dormant
Nov 1.4" 0" ❄️ Dormant
Dec 1.2" 0" ❄️ Dormant

Water needs are for active growing months only (Jun–Sep in Custer 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 ~12,775 GDD — county provides 790 GDD May not mature

Mulberries Planting Timeline — Custer County, ID

Mulberries Planting Calendar

Activity When Date Range
Transplant Outdoors July 9 Jul 9 – Jul 23

· 120" apart · Rows 144" apart

Month-by-Month Timeline

MonthActivities
January
February
March
April
May
June
July Transplant Outdoors
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: too_alkaline

🗺️ USDA Zone

Zone 5b

📆 Growing Season

79 days in Custer County

Growing Tips for Mulberries in Custer County

Direct sow Mulberries outdoors after June 18 in Custer County when soil has warmed and frost danger has passed.

Your 79.0-day growing season in Custer County is tight for Mulberries (730.0-1825.0 days to maturity). Start indoors and choose early-maturing varieties.

Custer County receives only 21" of rain annually. Mulberries needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.

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 Custer County, ID?

Custer County is in Zone 5b with an average last frost of June 18. Plan your Mulberries planting based on this frost date — see the calendar above for exact timing.

What planting zone is Custer County, ID?

Custer County, Idaho is in USDA Hardiness Zone 5b. The average last spring frost is June 18 and first fall frost is September 5.

When should I plant Mulberries in Custer County, ?

In Custer County, , plant Mulberries after the last frost (around June 18) and before the first frost (around September 5). Best results when soil holds above 50°F.

What growing zone is Custer County, for Mulberries?

Custer County sits in USDA Zone 5b. Mulberries grows reliably in zones 4a through 9b, so it's a good fit here.

Can Mulberries grow in Custer County's climate?

Yes — Mulberries grows well in Custer County's temperate climate. Custer County averages a 79-day frost-free season, with last frost around June 18 and first frost around September 5.

🌱

Your Custer County Garden Planner — Free

A 22-page printable planner built for Custer 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 Custer County, ID. 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.