Blog

When to Plant Rhubarb in Tillman County, OK

Rhubarb is a long-lived perennial vegetable grown for its tart, colorful stalks. Only the stalks are edible as the leaves contain toxic oxalic acid.

Tillman County, Oklahoma is in USDA Zone 7b. The average last spring frost is April 3 and the first fall frost is November 6, giving you a growing season of approximately 217 days.

At an elevation of 807 feet, Tillman County receives approximately 25.1 inches of rainfall annually with predominantly loam soil. Summer highs average 88ยฐF, providing good warmth for Rhubarb during the growing season.

Tillman County, OK (Zone 7b) Long season
217 days
Last Spring Frost April 3
217 growing days
First Fall Frost November 6

Tillman County Soil Profile

Soil Type

Loam

Soil pH

6.2-7.5

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season
Transplant: Apr 11
Recommended (50%) ✓ Fits season
Transplant: Apr 24
Safe Start (90%) ✓ Fits season
Transplant: May 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 Tillman County

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

Soil pH

Your soil pH (6.2โ€“7.5) overlaps with Rhubarb's range (6.0โ€“7.0), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is moderate (3.6%). Annual compost additions will help Rhubarb.

How to Plant Rhubarb

1"
Planting Depth
30"
Between Plants
42"
Between Rows

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.5″/week
You supply
0.5″/week
Watering frequency 1-2 times/week
Season total 993 gal / 100 sq ft

Monthly Watering Guide for Rhubarb

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

Month Rhubarb Needs Rainfall You Supplement Action
Jan โ€” 0.6" 0" โ„๏ธ Dormant
Feb โ€” 0.9" 0" โ„๏ธ Dormant
Mar โ€” 1.7" 0" โ„๏ธ Dormant
Apr 4.3" 2.8" 1.5" ๐Ÿ’ง Light watering
May 4.3" 3.7" 0.6" ๐Ÿ’ง Light watering
Jun 4.3" 4" 0.3" ๐Ÿ’ง Light watering
Jul 4.3" 3.3" 1" ๐Ÿ’ง Light watering
Aug 4.3" 2.9" 1.4" ๐Ÿ’ง Light watering
Sep 4.3" 2" 2.3" ๐Ÿšฟ Regular watering
Oct 4.3" 1.6" 2.7" ๐Ÿšฟ Regular watering
Nov 4.3" 0.8" 3.5" ๐Ÿšฟ Regular watering
Dec โ€” 0.7" 0" โ„๏ธ Dormant

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

Rhubarb 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.

Rhubarb needs ~8,760 GDD — county provides 3,472 GDD May not mature

Rhubarb Planting Timeline โ€” Tillman County, OK

Rhubarb Planting Calendar

Activity When Date Range
Transplant Outdoors April 24 Apr 24 โ€“ May 8

Plant 1" deep ยท 30" apart ยท Rows 42" 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 6โ€“7 ยท Your soil: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 7b

๐Ÿ“† Growing Season

217 days in Tillman County

Growing Tips for Rhubarb in Tillman County

Direct sow Rhubarb outdoors after April 03 in Tillman County when soil has warmed and frost danger has passed.

Your 217.0-day growing season in Tillman County is tight for Rhubarb (365.0-730.0 days to maturity). Start indoors and choose early-maturing varieties.

General growing tips

Plant crowns in early spring in rich, well-drained soil. Do not harvest stalks the first year. Pull (do not cut) stalks at harvest to avoid introducing rot.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Rhubarb in Tillman County, OK?

Tillman County is in Zone 7b with an average last frost of April 3. Plan your Rhubarb planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Tillman County, OK?

Tillman County, Oklahoma is in USDA Hardiness Zone 7b. The average last spring frost is April 3 and first fall frost is November 6.

๐ŸŒฑ

Plan Your Garden with Confidence

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