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When to Plant Rhubarb in Parmer County, TX

Parmer County, Texas Zone 7a May

Your May planting checklist for Parmer County, Texas

We've pulled the most time-sensitive tasks for Parmer County, Texas this May and put them front and centre. Tackle them in order.

Avg. last frost April 16
Avg. first frost October 23
Soil temp (4") 66°F
Watering Critical
Pest pressure Moderate
Daylight 13.8 hrs
  1. Plant out rhubarb

    Frost risk is low now in Parmer County, Texas. If you've been covering beds overnight, you can stop.

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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.

Parmer County, Texas is in USDA Zone 7a. The average last spring frost is April 16 and the first fall frost is October 23, giving you a growing season of approximately 190 days.

At an elevation of 1,686 feet, Parmer County receives approximately 53.4 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 95°F, so Rhubarb may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring — great for early planting — but Rhubarb will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Rhubarb root diseases.

Parmer County, TX (Zone 7a) Moderate season
190 days
Last Spring Frost April 16
190 growing days
First Fall Frost October 23

Parmer County Soil Profile

Soil Type

Sandy Loam

Soil pH

7.3-8.5

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season
Transplant: May 4
Recommended (50%) ✓ Fits season
Transplant: May 7
Safe Start (90%) ✓ Fits season
Transplant: May 23

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 Parmer County

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

Soil pH

Your soil pH (7.3–8.5) is more alkaline than Rhubarb prefers (6.0–7.0). Add sulfur or peat moss to lower pH.

Soil Texture

Sandy soil in Parmer County warms quickly in spring but drains fast. Rhubarb will need more frequent watering and regular compost additions to retain nutrients.

Organic Matter

Organic matter is low (0.9%). Add 2-3 inches of compost before planting Rhubarb.

How to Plant Rhubarb

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

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
1.2″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft
Drought risk

Water stress score is 8/10 — consider drought-tolerant varieties and mulching

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 3.4" 0" ❄️ Dormant
Feb 3" 0" ❄️ Dormant
Mar 3" 0" ❄️ Dormant
Apr 4.3" 1.8" 2.5" 🚿 Regular watering
May 4.3" 1.2" 3.1" 🚿 Regular watering
Jun 4.3" 1.8" 2.5" 🚿 Regular watering
Jul 4.3" 9.7" 0" ✅ Rainfall sufficient
Aug 4.3" 10.8" 0" ✅ Rainfall sufficient
Sep 4.3" 7.4" 0" ✅ Rainfall sufficient
Oct 4.3" 5.2" 0" ✅ Rainfall sufficient
Nov 2.8" 0" ❄️ Dormant
Dec 3.2" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Parmer County). Supplement amounts are based on average rainfall — 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" — 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.

Rhubarb needs ~11,634 GDD — county provides 4,037 GDD May not mature

Rhubarb Planting Timeline — Parmer County, TX

Rhubarb Planting Calendar

Activity When Date Range
Transplant Outdoors May 7 May 7 – May 21

Plant 1" deep · 30" apart · Rows 42" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1"/week · Natural rainfall sufficient

📅 Days to Maturity

365–730 days

🧪 Soil pH

Needs 6–7 · Your soil: too_alkaline

🗺️ USDA Zone

Zone 7a

📆 Growing Season

190 days in Parmer County

Growing Tips for Rhubarb in Parmer County

Direct sow Rhubarb outdoors after April 16 in Parmer County when soil has warmed and frost danger has passed.

Sandy soil in Parmer County dries quickly — mulch Rhubarb with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.

Your 190.0-day growing season in Parmer 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 Parmer County, TX?

Parmer County is in Zone 7a with an average last frost of April 16. Plan your Rhubarb planting based on this frost date — see the calendar above for exact timing.

What planting zone is Parmer County, TX?

Parmer County, Texas is in USDA Hardiness Zone 7a. The average last spring frost is April 16 and first fall frost is October 23.

🌱

Your Parmer County Garden Planner — Free

A 24-page printable planner built for Parmer County (Zone 7a). 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 Parmer County, TX. 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.