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When to Plant Elderberries in Fallon County, MT

Fallon County, Montana Zone 4b May

This month in Fallon County, Montana

Your garden in Fallon County, Montana is working on a schedule, even when you're not. Here's where you should be this May.

Avg. last frost May 20
Avg. first frost September 20
Soil temp (4") 37°F
Watering High
Pest pressure Low
Daylight 14.8 hrs
Before June arrives, get these ready
  • Transplants going out: elderberries

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Elderberries are fast-growing shrubs or small trees producing clusters of small, dark berries used for syrups, wines, and immune-boosting preparations. The flowers are also edible.

Fallon County, Montana is in USDA Zone 4b. The average last spring frost is May 20 and the first fall frost is September 20, giving you a growing season of approximately 123 days.

At an elevation of 6,441 feet, Fallon County receives approximately 19.8 inches of rainfall annually with predominantly loam soil. Summer highs average 81°F, so choose short-season varieties of Elderberries to ensure they mature before fall. With low rainfall, drip irrigation is essential for growing Elderberries successfully. Mulch heavily to conserve soil moisture.

Fallon County, MT (Zone 4b) Short season
123 days
Last Spring Frost May 20
123 growing days
First Fall Frost September 20

Fallon County Soil Profile

Soil Type

Loam

Soil pH

6.2-8.3

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season
Transplant: Jun 11
Recommended (50%) ✓ Fits season
Transplant: Jun 17
Safe Start (90%) ✓ Fits season
Transplant: Jul 6

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 Fallon County

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

Soil pH

Your soil pH (6.2–8.3) is more alkaline than Elderberries prefers (5.5–6.5). Add sulfur or peat moss to lower pH.

Soil Texture

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

Organic Matter

Organic matter is moderate (2.2%). Annual compost additions will help Elderberries.

How to Plant Elderberries

120"
Between Plants
144"
Between Rows

Plant Water Budget

Plant needs
0.8″/week
Rainfall provides
0.7″/week
You supply
0.2″/week
Watering frequency Only during dry spells
Season total 163 gal / 100 sq ft
Drought risk

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

Monthly Watering Guide for Elderberries

Elderberries needs approximately 0.8 inches of water per week (3.5" per month). Here's how your county's rainfall compares month by month.

Month Elderberries Needs Rainfall You Supplement Action
Jan 1.3" 0" ❄️ Dormant
Feb 1.3" 0" ❄️ Dormant
Mar 1.8" 0" ❄️ Dormant
Apr 2.1" 0" ❄️ Dormant
May 3.5" 2.7" 0.8" 💧 Light watering
Jun 3.5" 1.4" 2.1" 🚿 Regular watering
Jul 3.5" 1.6" 1.9" 🚿 Regular watering
Aug 3.5" 1.9" 1.6" 💧 Light watering
Sep 3.5" 1.6" 1.9" 🚿 Regular watering
Oct 1.7" 0" ❄️ Dormant
Nov 1.2" 0" ❄️ Dormant
Dec 1.2" 0" ❄️ Dormant

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

Elderberries 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.

Elderberries needs ~9,809 GDD — county provides 1,322 GDD May not mature

Elderberries Planting Timeline — Fallon County, MT

Elderberries Planting Calendar

Activity When Date Range
Transplant Outdoors June 17 Jun 17 – Jul 1

· 120" apart · Rows 144" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.8"/week · Only during dry spells

📅 Days to Maturity

730–1095 days

🧪 Soil pH

Needs 5.5–6.5 · Your soil: too_alkaline

🗺️ USDA Zone

Zone 4b

📆 Growing Season

123 days in Fallon County

Growing Tips for Elderberries in Fallon County

Direct sow Elderberries outdoors after May 20 in Fallon County when soil has warmed and frost danger has passed.

Your 123.0-day growing season in Fallon County is tight for Elderberries (730.0-1095.0 days to maturity). Start indoors and choose early-maturing varieties.

General growing tips

Plant at least two varieties for cross-pollination. Prune annually to remove old canes and maintain shape. Berries must be cooked before eating as raw berries are mildly toxic.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Elderberries in Fallon County, MT?

Fallon County is in Zone 4b with an average last frost of May 20. Plan your Elderberries planting based on this frost date — see the calendar above for exact timing.

What planting zone is Fallon County, MT?

Fallon County, Montana is in USDA Hardiness Zone 4b. The average last spring frost is May 20 and first fall frost is September 20.

🌱

Your Fallon County Garden Planner — Free

A 24-page printable planner built for Fallon County (Zone 4b). 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 Fallon County, MT. 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.