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When to Plant Blueberries in Conejos County, CO

Blueberries are long-lived shrubs producing sweet, antioxidant-rich berries. They require acidic soil and are attractive ornamental plants with fall color and spring flowers.

Conejos County, Colorado is in USDA Zone 4b. The average last spring frost is June 9 and the first fall frost is September 17, giving you a growing season of approximately 100 days.

At an elevation of 6,770 feet, Conejos County receives approximately 24.1 inches of rainfall annually with predominantly loam soil. Summer highs average 82ยฐF, so choose short-season varieties of Blueberries to ensure they mature before fall.

Conejos County, CO (Zone 4b) Short season
100 days
Last Spring Frost June 9
100 growing days
First Fall Frost September 17

Conejos County Soil Profile

Soil Type

Loam

Soil pH

6.6-7.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season
Transplant: Jun 27
Recommended (50%) ✓ Fits season
Transplant: Jul 7
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 Conejos County

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

Soil pH

Your soil pH (6.6โ€“7.8) is more alkaline than Blueberries prefers (4.5โ€“5.5). Add sulfur or peat moss to lower pH.

Soil Texture

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

Organic Matter

Organic matter is moderate (2.6%). Annual compost additions will help Blueberries.

How to Plant Blueberries

48"
Between Plants
72"
Between Rows

How Much Blueberries to Grow

5-10 lbs
Average yield per plant
2
Plants per person
48 sq ft
Space per person

For a family of 4, plant approximately 8 blueberries plants in about 192 sq ft. In Conejos County's 100-day season, you'll have plenty of time for a full harvest. Plan your garden layout →

Plant Water Budget

Plant needs
1.2″/week
Rainfall provides
1.0″/week
You supply
0.2″/week
Watering frequency Only during dry spells
Season total 201 gal / 100 sq ft
Drought risk

Water stress score is 6/10 โ€” consider drought-tolerant varieties and mulching

Monthly Watering Guide for Blueberries

Blueberries needs approximately 1.2 inches of water per week (5.2" per month). Here's how your county's rainfall compares month by month.

Month Blueberries Needs Rainfall You Supplement Action
Jan โ€” 1.8" 0" โ„๏ธ Dormant
Feb โ€” 1.3" 0" โ„๏ธ Dormant
Mar โ€” 2" 0" โ„๏ธ Dormant
Apr โ€” 2.8" 0" โ„๏ธ Dormant
May โ€” 2.7" 0" โ„๏ธ Dormant
Jun 5.2" 1.7" 3.5" ๐Ÿšฟ Regular watering
Jul 5.2" 1.8" 3.4" ๐Ÿšฟ Regular watering
Aug 5.2" 2.5" 2.7" ๐Ÿšฟ Regular watering
Sep 5.2" 2.1" 3.1" ๐Ÿšฟ Regular watering
Oct โ€” 2.3" 0" โ„๏ธ Dormant
Nov โ€” 1.7" 0" โ„๏ธ Dormant
Dec โ€” 1.5" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Junโ€“Sep in Conejos County). Supplement amounts are based on average rainfall โ€” actual needs vary with temperature, soil, and mulching.

Blueberries 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.

Blueberries needs ~10,494 GDD — county provides 1,150 GDD May not mature

Blueberries Planting Timeline โ€” Conejos County, CO

Blueberries Planting Calendar

Activity When Date Range
Transplant Outdoors July 7 Jul 7 โ€“ Jul 21

ยท 48" apart ยท Rows 72" apart

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

1.2"/week ยท Only during dry spells

๐Ÿ“… Days to Maturity

730โ€“1095 days

๐Ÿงช Soil pH

Needs 4.5โ€“5.5 ยท Your soil: too_alkaline

๐Ÿ—บ๏ธ USDA Zone

Zone 4b

๐Ÿ“† Growing Season

100 days in Conejos County

Growing Tips for Blueberries in Conejos County

Direct sow Blueberries outdoors after June 09 in Conejos County when soil has warmed and frost danger has passed.

Your 100.0-day growing season in Conejos County is tight for Blueberries (730.0-1095.0 days to maturity). Start indoors and choose early-maturing varieties.

Conejos County receives only 24" of rain annually. Blueberries needs consistent moisture โ€” install drip irrigation or water deeply 2-3 times per week.

General growing tips

Plant at least two varieties for cross-pollination. Acidify soil with sulfur or pine needle mulch to maintain pH 4.5-5.5. Protect ripening berries from birds with netting.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Blueberries in Conejos County, CO?

Conejos County is in Zone 4b with an average last frost of June 9. Plan your Blueberries planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Conejos County, CO?

Conejos County, Colorado is in USDA Hardiness Zone 4b. The average last spring frost is June 9 and first fall frost is September 17.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Conejos County gardeners in Zone 4b 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 Conejos County, CO. Local conditions may vary. Last updated: April 2026.