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When to Plant Chard in San Jacinto County, TX

San Jacinto County, Texas Zone 9a May

Your May gardening checklist

Your garden in San Jacinto County, Texas is working on a schedule, even when you're not. Here's where you should be this May.

Avg. last frost February 18
Avg. first frost December 1
Soil temp (4") 71°F
Watering Low
Pest pressure High
Daylight 13.5 hrs
  1. Bring in the chard

    This is the payoff month. Bring a basket, bring a friend, and get into the beds.

Looking ahead to June
  • First harvests: chard

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Swiss chard is a colorful, heat-tolerant green with large crinkled leaves and vibrant stalks in red, yellow, and white. Both the leaves and stems are edible and nutritious.

San Jacinto County, Texas is in USDA Zone 9a. The average last spring frost is February 18 and the first fall frost is December 1, giving you a growing season of approximately 286 days.

At an elevation of 6 feet, San Jacinto County receives approximately 71.3 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 94°F, providing good warmth for Chard during the growing season. Sandy soil warms quickly in spring — great for early planting — but Chard will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Chard root diseases.

San Jacinto County, TX (Zone 9a) Year-round
286 days
Last Spring Frost February 18
286 growing days
First Fall Frost December 1

San Jacinto County Soil Profile

Soil Type

Sandy Loam

Soil pH

5.3-6.7

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (182 days to spare)
Start indoors: Jan 13 Transplant: Feb 10 🍅 Harvest: Apr 7 – May 26
Recommended (50%) ✓ Fits season (181 days to spare)
Start indoors: Jan 21 Transplant: Feb 18 🍅 Harvest: Apr 15 – Jun 3
Safe Start (90%) ✓ Fits season (178 days to spare)
Start indoors: Feb 9 Transplant: Mar 9 🍅 Harvest: May 4 – Jun 22

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 San Jacinto County

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

Soil pH

Your soil pH (5.3–6.7) overlaps with Chard's range (6.0–7.0), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is moderate (2.2%). Annual compost additions will help Chard.

How to Plant Chard

1"
Planting Depth
15"
Between Plants
24"
Between Rows

Fall planting: Sow 8 weeks before your first frost date for a fall harvest.

Succession Planting Chard

6
successive plantings in your 286-day season

Sow every 5.7 weeks. Last sowing by Oct 02 to harvest before frost.

For a dedicated fall crop, sow by Oct 06.

Plant Water Budget

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

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

Monthly Watering Guide for Chard

Chard 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 Chard Needs Rainfall You Supplement Action
Jan 1.7" 0" ❄️ Dormant
Feb 3.5" 2.5" 1" 💧 Light watering
Mar 3.5" 4.2" 0" ✅ Rainfall sufficient
Apr 3.5" 8.5" 0" ✅ Rainfall sufficient
May 3.5" 9.5" 0" ✅ Rainfall sufficient
Jun 3.5" 11.4" 0" ✅ Rainfall sufficient
Jul 3.5" 9.2" 0" ✅ Rainfall sufficient
Aug 3.5" 8" 0" ✅ Rainfall sufficient
Sep 3.5" 6.7" 0" ✅ Rainfall sufficient
Oct 3.5" 5.2" 0" ✅ Rainfall sufficient
Nov 3.5" 2.6" 0.9" 💧 Light watering
Dec 3.5" 1.9" 1.6" 💧 Light watering

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

Chard 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.

Chard needs ~1,128 GDD — county provides 5,883 GDD Excellent fit

Chard Planting Timeline — San Jacinto County, TX

Chard Planting Calendar

Activity When Date Range
Start Indoors January 21 Jan 21 – Feb 4
Transplant Outdoors February 18 Feb 18 – Mar 4
Direct Sow January 28 Jan 28 – Feb 18
Harvest April 15 Apr 15 – Jun 3
Fall Sowing October 6 Oct 6 – Oct 20

Plant 1" deep · 15" apart · Rows 24" apart

Month-by-Month Timeline

MonthActivities
January Start Indoors Direct Sow
February Start Indoors Transplant Outdoors Direct Sow
March Transplant Outdoors
April Harvest
May Harvest
June Harvest
July
August
September
October Fall Sowing
November
December

Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

0.8"/week · Natural rainfall sufficient

📅 Days to Maturity

50–60 days

🧪 Soil pH

Needs 6–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 9a

📆 Growing Season

286 days in San Jacinto County

Growing Tips for Chard in San Jacinto County

Direct sow Chard outdoors after February 18 in San Jacinto County when soil has warmed and frost danger has passed.

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

Summer highs in San Jacinto County reach 94°F — grow Chard as a spring or fall crop. Use shade cloth if planting in summer.

General growing tips

Direct sow or transplant after last frost. Harvest outer leaves regularly to encourage continuous production. Chard tolerates both heat and light frost.

Companion Planting

Good Companions

Avoid Planting Near

  • Corn
  • Cucumbers

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Chard in San Jacinto County, TX?

San Jacinto County is in Zone 9a with an average last frost of February 18. Plan your Chard planting based on this frost date — see the calendar above for exact timing.

What planting zone is San Jacinto County, TX?

San Jacinto County, Texas is in USDA Hardiness Zone 9a. The average last spring frost is February 18 and first fall frost is December 1.

🌱

Your San Jacinto County Garden Planner — Free

A 24-page printable planner built for San Jacinto 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 San Jacinto 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.