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When to Plant Mulberries in Fremont County, CO

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

Fremont County, Colorado is in USDA Zone 5b. The average last spring frost is May 23 and the first fall frost is September 25, giving you a growing season of approximately 125 days.

At an elevation of 6,575 feet, Fremont County receives approximately 18.5 inches of rainfall annually with predominantly loam soil. Summer highs average 84ยฐF, so choose short-season varieties of Mulberries to ensure they mature before fall. With low rainfall, drip irrigation is essential for growing Mulberries successfully. Mulch heavily to conserve soil moisture.

Fremont County, CO (Zone 5b) Short season
125 days
Last Spring Frost May 23
125 growing days
First Fall Frost September 25

Fremont County Soil Profile

Soil Type

Loam

Soil pH

6.7-8.3

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season
Transplant: Jun 1
Recommended (50%) ✓ Fits season
Transplant: Jun 13
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 Fremont County

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

Soil pH

Your soil pH (6.7โ€“8.3) is more alkaline than Mulberries prefers (5.5โ€“7.0). Add sulfur or peat moss to lower pH.

Soil Texture

The loam soil in Fremont County is excellent for Mulberries โ€” good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (2.6%). 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
0.6″/week
You supply
0.5″/week
Watering frequency 1-2 times/week
Season total 505 gal / 100 sq ft
Drought risk

Water stress score is 8/10 โ€” 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 โ€” 1.5" 0" โ„๏ธ Dormant
Feb โ€” 1.1" 0" โ„๏ธ Dormant
Mar โ€” 1.6" 0" โ„๏ธ Dormant
Apr โ€” 2.2" 0" โ„๏ธ Dormant
May 4.3" 2" 2.3" ๐Ÿšฟ Regular watering
Jun 4.3" 1.5" 2.8" ๐Ÿšฟ Regular watering
Jul 4.3" 1.4" 2.9" ๐Ÿšฟ Regular watering
Aug 4.3" 1.7" 2.6" ๐Ÿšฟ Regular watering
Sep 4.3" 1.5" 2.8" ๐Ÿšฟ Regular watering
Oct โ€” 1.7" 0" โ„๏ธ Dormant
Nov โ€” 1.4" 0" โ„๏ธ Dormant
Dec โ€” 1" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Mayโ€“Sep in Fremont County). Supplement amounts are based on average rainfall โ€” 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" โ€” every day above 50ยฐF 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 ~16,608 GDD — county provides 1,625 GDD May not mature

Mulberries Planting Timeline โ€” Fremont County, CO

Mulberries Planting Calendar

Activity When Date Range
Transplant Outdoors June 13 Jun 13 โ€“ Jun 27

ยท 120" apart ยท Rows 144" apart

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

1"/week ยท 1-2 times/week

๐Ÿ“… Days to Maturity

730โ€“1825 days

๐Ÿงช Soil pH

Needs 5.5โ€“7 ยท Your soil: too_alkaline

๐Ÿ—บ๏ธ USDA Zone

Zone 5b

๐Ÿ“† Growing Season

125 days in Fremont County

Growing Tips for Mulberries in Fremont County

Direct sow Mulberries outdoors after May 23 in Fremont County when soil has warmed and frost danger has passed.

Your 125.0-day growing season in Fremont County is tight for Mulberries (730.0-1825.0 days to maturity). Start indoors and choose early-maturing varieties.

Fremont County receives only 18" of rain annually. Mulberries needs consistent moisture โ€” 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 Fremont County, CO?

Fremont County is in Zone 5b with an average last frost of May 23. Plan your Mulberries planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Fremont County, CO?

Fremont County, Colorado is in USDA Hardiness Zone 5b. The average last spring frost is May 23 and first fall frost is September 25.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Fremont County gardeners in Zone 5b organize planting dates, track what's growing, and never miss a planting window.

Get Your Free Garden Planner →

Free download. Plan your entire garden season in minutes.

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