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When to Plant Asparagus in DeWitt County, TX

DeWitt County, Texas Zone 9a May

This month in DeWitt County, Texas

May rewards gardeners who work with the weather, not against it. Here's how to stay in step this month in DeWitt County, Texas.

Avg. last frost March 2
Avg. first frost November 26
Soil temp (4") 71°F
Watering Low
Pest pressure High
Daylight 13.5 hrs

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Asparagus is a long-lived perennial vegetable that produces tender spears each spring for 15-20 years once established. It requires patience but rewards with reliable harvests.

DeWitt County, Texas is in USDA Zone 9a. The average last spring frost is March 2 and the first fall frost is November 26, giving you a growing season of approximately 269 days.

At an elevation of 1,649 feet, DeWitt County receives approximately 62.1 inches of rainfall annually with predominantly loam soil. Summer highs average 91°F, providing good warmth for Asparagus during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Asparagus root diseases.

DeWitt County, TX (Zone 9a) Long season
269 days
Last Spring Frost March 2
269 growing days
First Fall Frost November 26
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DeWitt County Soil Profile

Soil Type

Loam

Soil pH

6.8-7.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season
Transplant: Mar 4
Recommended (50%) ✓ Fits season
Transplant: Mar 16
Safe Start (90%) ✓ Fits season
Transplant: Apr 8

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 DeWitt County

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

Soil pH

Your soil pH (6.8–7.8) overlaps with Asparagus's range (6.5–7.5), though not a perfect match.

Soil Texture

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

Drainage

Drainage is adequate for Asparagus.

Organic Matter

Organic matter is low (1.9%). Add 2-3 inches of compost before planting Asparagus.

How to Plant Asparagus

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

Plant Water Budget

Plant needs
0.8″/week
Rainfall provides
1.0″/week
You supply
0.1″/week
Watering frequency Only during dry spells
Season total 202 gal / 100 sq ft
Drought risk

Water stress score is 6/10 — consider drought-tolerant varieties and mulching

Monthly Watering Guide for Asparagus

Asparagus needs approximately 0.8 inches of water per week (3.5" per month). Here's how your county's rainfall compares month by month.

Month Asparagus Needs Rainfall You Supplement Action
Jan 1.8" 0" ❄️ Dormant
Feb 2.1" 0" ❄️ Dormant
Mar 3.5" 4" 0" ✅ Rainfall sufficient
Apr 3.5" 5.9" 0" ✅ Rainfall sufficient
May 3.5" 9.1" 0" ✅ Rainfall sufficient
Jun 3.5" 11.3" 0" ✅ Rainfall sufficient
Jul 3.5" 6.9" 0" ✅ Rainfall sufficient
Aug 3.5" 7.9" 0" ✅ Rainfall sufficient
Sep 3.5" 5.6" 0" ✅ Rainfall sufficient
Oct 3.5" 3.7" 0" ✅ Rainfall sufficient
Nov 3.5" 2.3" 1.2" 💧 Light watering
Dec 1.5" 0" ❄️ Dormant

Water needs are for active growing months only (Mar–Nov in DeWitt County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Asparagus 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.

Asparagus needs ~16,653 GDD — county provides 4,909 GDD May not mature

Asparagus Planting Timeline — DeWitt County, TX

Asparagus Planting Calendar

Activity When Date Range
Transplant Outdoors March 16 Mar 16 – Mar 30

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

Month-by-Month Timeline

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

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.8"/week · Only during dry spells

📅 Days to Maturity

730–1095 days

🧪 Soil pH

Needs 6.5–7.5 · Your soil: acceptable

🗺️ USDA Zone

Zone 9a

📆 Growing Season

269 days in DeWitt County

Growing Tips for Asparagus in DeWitt County

Direct sow Asparagus outdoors after March 02 in DeWitt County when soil has warmed and frost danger has passed.

Your 269.0-day growing season in DeWitt County is tight for Asparagus (730.0-1095.0 days to maturity). Start indoors and choose early-maturing varieties.

General growing tips

Plant crowns in deep trenches with compost. Do not harvest spears for the first two years to allow root establishment. Mulch heavily to suppress weeds and retain moisture.

Companion Planting

Good Companions

Avoid Planting Near

  • Garlic
  • Onion

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Asparagus in DeWitt County, TX?

DeWitt County is in Zone 9a with an average last frost of March 2. Plan your Asparagus planting based on this frost date — see the calendar above for exact timing.

What planting zone is DeWitt County, TX?

DeWitt County, Texas is in USDA Hardiness Zone 9a. The average last spring frost is March 2 and first fall frost is November 26.

🌱

Your DeWitt County Garden Planner — Free

A 24-page printable planner built for DeWitt County (Zone 9a). 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 DeWitt 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.