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When to Plant Spinach in Jefferson County, TX

Jefferson County, Texas Zone 9b May

Your May game plan for Jefferson County, Texas

May is a pivotal month for Jefferson County, Texas gardens. Focus on these tasks first and you'll set up the rest of the season for success.

Avg. last frost February 13
Avg. first frost December 6
Soil temp (4") 77°F
Watering Low
Pest pressure High
Daylight 13.5 hrs
  1. Harvest spinach as they ripen

    The more you pick, the more the plant produces. Letting fruit overripen tells the plant it's time to stop.

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Spinach is a nutrient-packed cool-season green that grows quickly in spring and fall. It is rich in iron, vitamins, and antioxidants and excellent raw or cooked.

Jefferson County, Texas is in USDA Zone 9b. The average last spring frost is February 13 and the first fall frost is December 6, giving you a growing season of approximately 296 days.

At an elevation of 349 feet, Jefferson County receives approximately 64.9 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 101°F, so Spinach may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring — great for early planting — but Spinach will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Spinach root diseases.

Jefferson County, TX (Zone 9b) Year-round
296 days
Last Spring Frost February 13
296 growing days
First Fall Frost December 6

Jefferson County Soil Profile

Soil Type

Sandy Loam

Soil pH

5.4-6.5

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (210 days to spare)
Start indoors: Dec 27 Transplant: Jan 24 🍅 Harvest: Feb 28 – May 2
Recommended (50%) ✓ Fits season (198 days to spare)
Start indoors: Jan 16 Transplant: Feb 13 🍅 Harvest: Mar 20 – May 22
Safe Start (90%) ✓ Fits season (195 days to spare)
Start indoors: Feb 6 Transplant: Mar 6 🍅 Harvest: Apr 10 – Jun 12

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 Jefferson County

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

Soil pH

Your soil pH (5.4–6.5) is more acidic than Spinach prefers (6.5–7.5). Add garden lime to raise pH.

Soil Texture

Sandy soil in Jefferson County warms quickly in spring but drains fast. Spinach 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 Spinach.

How to Plant Spinach

0.5"
Planting Depth
6"
Between Plants
12"
Between Rows

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

Succession Planting Spinach

10
successive plantings in your 296-day season

Sow every 4 weeks. Last sowing by Oct 17 to harvest before frost.

For a dedicated fall crop, sow by Oct 11.

Plant Water Budget

Plant needs
0.7″/week
Rainfall provides
0.9″/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 Spinach

Spinach needs approximately 0.7 inches of water per week (3" per month). Here's how your county's rainfall compares month by month.

Month Spinach Needs Rainfall You Supplement Action
Jan 1.6" 0" ❄️ Dormant
Feb 3" 2.1" 0.9" 💧 Light watering
Mar 3" 4.4" 0" ✅ Rainfall sufficient
Apr 3" 6.3" 0" ✅ Rainfall sufficient
May 3" 9.8" 0" ✅ Rainfall sufficient
Jun 3" 10.7" 0" ✅ Rainfall sufficient
Jul 3" 8.8" 0" ✅ Rainfall sufficient
Aug 3" 6.6" 0" ✅ Rainfall sufficient
Sep 3" 6.6" 0" ✅ Rainfall sufficient
Oct 3" 4.4" 0" ✅ Rainfall sufficient
Nov 3" 2.1" 0.9" 💧 Light watering
Dec 3" 1.6" 1.4" 💧 Light watering

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

Spinach 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.

Spinach needs ~1,094 GDD — county provides 7,647 GDD Excellent fit

Spinach Planting Timeline — Jefferson County, TX

Spinach Planting Calendar

Activity When Date Range
Start Indoors January 16 Jan 16 – Jan 30
Transplant Outdoors February 13 Feb 13 – Feb 27
Direct Sow January 23 Jan 23 – Feb 13
Harvest March 20 Mar 20 – May 22
Fall Sowing October 11 Oct 11 – Oct 25

Plant 0.5" deep · 6" apart · Rows 12" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

0.7"/week · Natural rainfall sufficient

📅 Days to Maturity

35–50 days

🧪 Soil pH

Needs 6.5–7.5 · Your soil: too_acidic

🗺️ USDA Zone

Zone 9b

📆 Growing Season

296 days in Jefferson County

Growing Tips for Spinach in Jefferson County

Direct sow Spinach outdoors after February 13 in Jefferson County when soil has warmed and frost danger has passed.

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

Summer highs in Jefferson County reach 101°F — grow Spinach as a spring or fall crop. Use shade cloth if planting in summer.

Your generous 297.0-day season in Jefferson County allows multiple plantings of Spinach. Sow every 17.0 days for continuous harvest.

General growing tips

Direct sow as soon as soil can be worked in spring. Plant in partial shade for summer crops to delay bolting. Succession plant every 2 weeks for continuous harvest.

Recommended Spinach Varieties for Jefferson County

Slow-bolting spinach for warm springs — best as fall crop here

Bloomsdale Long Standing Tyee Space

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

🌾 Save Your Own Spinach Seeds
Life Cycle Annual
Pollination Wind Pollinated
How to Collect Let plants bolt. Harvest seed stalks when seeds turn tan.
Storage Store airtight; viable 5 years at 35°F, under 45% humidity.

Wind pollinated — isolate 1/2 mile for purity. Easy to let bolt in heat.

Frequently Asked Questions

When should I plant Spinach in Jefferson County, TX?

Jefferson County is in Zone 9b with an average last frost of February 13. Plan your Spinach planting based on this frost date — see the calendar above for exact timing.

What planting zone is Jefferson County, TX?

Jefferson County, Texas is in USDA Hardiness Zone 9b. The average last spring frost is February 13 and first fall frost is December 6.

🌱

Your Jefferson County Garden Planner — Free

A 24-page printable planner built for Jefferson County (Zone 9b). 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 Jefferson 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.