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When to Plant Blackberries in Haskell County, OK

Blackberries are vigorous bramble fruits that produce sweet-tart berries on thorny or thornless canes. They are prolific producers and relatively low-maintenance once established.

Haskell County, Oklahoma is in USDA Zone 7a. The average last spring frost is March 28 and the first fall frost is November 3, giving you a growing season of approximately 220 days.

At an elevation of 691 feet, Haskell County receives approximately 29.2 inches of rainfall annually with predominantly loam soil. Summer highs average 91ยฐF, providing good warmth for Blackberries during the growing season.

Haskell County, OK (Zone 7a) Long season
220 days
Last Spring Frost March 28
220 growing days
First Fall Frost November 3

Haskell County Soil Profile

Soil Type

Loam

Soil pH

6.5-7.5

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season
Transplant: Apr 11
Recommended (50%) ✓ Fits season
Transplant: Apr 18
Safe Start (90%) ✓ Fits season
Transplant: May 5

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 Haskell County

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

Soil pH

Your soil pH (6.5โ€“7.5) overlaps with Blackberries's range (5.5โ€“7.0), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is excellent (4.3%) โ€” Blackberries will thrive.

How to Plant Blackberries

24"
Between Plants
72"
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 1,040 gal / 100 sq ft
Drought risk

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

Monthly Watering Guide for Blackberries

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

Month Blackberries Needs Rainfall You Supplement Action
Jan โ€” 0.7" 0" โ„๏ธ Dormant
Feb โ€” 1.1" 0" โ„๏ธ Dormant
Mar 4.3" 1.9" 2.4" ๐Ÿšฟ Regular watering
Apr 4.3" 2.9" 1.4" ๐Ÿ’ง Light watering
May 4.3" 4" 0.3" ๐Ÿ’ง Light watering
Jun 4.3" 4.8" 0" โœ… Rainfall sufficient
Jul 4.3" 3.8" 0.5" ๐Ÿ’ง Light watering
Aug 4.3" 3" 1.3" ๐Ÿ’ง Light watering
Sep 4.3" 3.1" 1.2" ๐Ÿ’ง Light watering
Oct 4.3" 2.1" 2.2" ๐Ÿšฟ Regular watering
Nov 4.3" 1" 3.3" ๐Ÿšฟ Regular watering
Dec โ€” 0.7" 0" โ„๏ธ Dormant

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

Blackberries 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.

Blackberries needs ~9,992 GDD — county provides 4,015 GDD May not mature

Blackberries Planting Timeline โ€” Haskell County, OK

Blackberries Planting Calendar

Activity When Date Range
Transplant Outdoors April 18 Apr 18 โ€“ May 2

ยท 24" apart ยท Rows 72" apart

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March โ€”
April Transplant Outdoors
May Transplant Outdoors
June โ€”
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

365โ€“730 days

๐Ÿงช Soil pH

Needs 5.5โ€“7 ยท Your soil: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 7a

๐Ÿ“† Growing Season

220 days in Haskell County

Growing Tips for Blackberries in Haskell County

Direct sow Blackberries outdoors after March 28 in Haskell County when soil has warmed and frost danger has passed.

Your 220.0-day growing season in Haskell County is tight for Blackberries (365.0-730.0 days to maturity). Start indoors and choose early-maturing varieties.

General growing tips

Plant bare-root canes in spring. Provide a sturdy trellis system. Prune out spent fruiting canes after harvest. New canes fruit in their second year (floricanes).

Companion Planting

Good Companions

Avoid Planting Near

  • Tomatoes
  • Peppers

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Blackberries in Haskell County, OK?

Haskell County is in Zone 7a with an average last frost of March 28. Plan your Blackberries planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Haskell County, OK?

Haskell County, Oklahoma is in USDA Hardiness Zone 7a. The average last spring frost is March 28 and first fall frost is November 3.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Haskell County gardeners in Zone 7a 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 Haskell County, OK. Local conditions may vary. Last updated: April 2026.