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When to Plant Rhubarb in Kendall County, TX

Kendall County, Texas Zone 8b May

This month in Kendall County, Texas

Each item below is timed to Kendall County, Texas's frost dates and soil temperatures. Skip nothing, stress about nothing.

Avg. last frost March 9
Avg. first frost November 20
Soil temp (4") 67°F
Watering Low
Pest pressure High
Daylight 13.5 hrs

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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.

Kendall County, Texas is in USDA Zone 8b. The average last spring frost is March 9 and the first fall frost is November 20, giving you a growing season of approximately 256 days.

At an elevation of 2,187 feet, Kendall County receives approximately 54.6 inches of rainfall annually with predominantly loam soil. Summer highs average 95°F, so Rhubarb may need afternoon shade and extra watering during peak heat. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Rhubarb root diseases.

Kendall County, TX (Zone 8b) Long season
256 days
Last Spring Frost March 9
256 growing days
First Fall Frost November 20

Kendall County Soil Profile

Soil Type

Loam

Soil pH

6.4-7.4

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season
Transplant: Mar 21
Recommended (50%) ✓ Fits season
Transplant: Mar 30
Safe Start (90%) ✓ Fits season
Transplant: Apr 28

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 Kendall County

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

Soil pH

Your soil pH (6.4–7.4) overlaps with Rhubarb's range (6.0–7.0), though not a perfect match.

Soil Texture

The loam soil in Kendall County is excellent for Rhubarb — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (2.1%). 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
0.9″/week
You supply
0.1″/week
Watering frequency Only during dry spells
Season total 237 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 1.5" 0" ❄️ Dormant
Feb 2.2" 0" ❄️ Dormant
Mar 4.3" 3.3" 1" 💧 Light watering
Apr 4.3" 6.5" 0" ✅ Rainfall sufficient
May 4.3" 7.6" 0" ✅ Rainfall sufficient
Jun 4.3" 8.2" 0" ✅ Rainfall sufficient
Jul 4.3" 6.9" 0" ✅ Rainfall sufficient
Aug 4.3" 6.3" 0" ✅ Rainfall sufficient
Sep 4.3" 5.4" 0" ✅ Rainfall sufficient
Oct 4.3" 3.4" 0.9" 💧 Light watering
Nov 4.3" 1.9" 2.4" 🚿 Regular watering
Dec 1.3" 0" ❄️ Dormant

Water needs are for active growing months only (Mar–Nov in Kendall 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 5,440 GDD May not mature

Rhubarb Planting Timeline — Kendall County, TX

Rhubarb Planting Calendar

Activity When Date Range
Transplant Outdoors March 30 Mar 30 – Apr 13

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1"/week · Only during dry spells

📅 Days to Maturity

365–730 days

🧪 Soil pH

Needs 6–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 8b

📆 Growing Season

256 days in Kendall County

Growing Tips for Rhubarb in Kendall County

Direct sow Rhubarb outdoors after March 09 in Kendall County when soil has warmed and frost danger has passed.

Your 256.0-day growing season in Kendall 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 Kendall County, TX?

Kendall County is in Zone 8b with an average last frost of March 9. Plan your Rhubarb planting based on this frost date — see the calendar above for exact timing.

What planting zone is Kendall County, TX?

Kendall County, Texas is in USDA Hardiness Zone 8b. The average last spring frost is March 9 and first fall frost is November 20.

🌱

Your Kendall County Garden Planner — Free

A 24-page printable planner built for Kendall County (Zone 8b). 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 Kendall 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.