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When to Plant Malabar Spinach in Jefferson County, OK

Jefferson County, Oklahoma Zone 8a May

Your May planting checklist for Jefferson County, Oklahoma

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

Avg. last frost March 26
Avg. first frost November 9
Soil temp (4") 67°F
Watering Moderate
Pest pressure Moderate
Daylight 13.8 hrs
  1. Time to start malabar spinach inside

    Label every cell. You will absolutely forget which is which otherwise.

June prep starts now
  • First harvests: malabar spinach

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Malabar spinach is a tropical vine with thick, succulent leaves that taste similar to spinach. Unlike true spinach, it thrives in heat and humidity.

Jefferson County, Oklahoma is in USDA Zone 8a. The average last spring frost is March 26 and the first fall frost is November 9, giving you a growing season of approximately 228 days.

At an elevation of 883 feet, Jefferson County receives approximately 24.7 inches of rainfall annually with predominantly loam soil. Summer highs average 91°F, providing good warmth for Malabar Spinach during the growing season.

Jefferson County, OK (Zone 8a) Long season
228 days
Last Spring Frost March 26
228 growing days
First Fall Frost November 9

Jefferson County Soil Profile

Soil Type

Loam

Soil pH

6.6-7.5

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (131 days to spare)
Start indoors: Jan 26 Transplant: Mar 30 🍅 Harvest: May 25 – Jun 22
Recommended (50%) ✓ Fits season (130 days to spare)
Start indoors: Feb 5 Transplant: Apr 9 🍅 Harvest: Jun 4 – Jul 2
Safe Start (90%) ✓ Fits season (125 days to spare)
Start indoors: Feb 25 Transplant: Apr 29 🍅 Harvest: Jun 24 – Jul 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 Jefferson County

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

Soil pH

Your soil pH (6.6–7.5) is within Malabar Spinach's preferred range (6.0–7.5).

Soil Texture

The loam soil in Jefferson County is excellent for Malabar Spinach — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is excellent (4.1%) — Malabar Spinach will thrive.

How to Plant Malabar Spinach

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

Succession Planting Malabar Spinach

4
successive plantings in your 228-day season

Sow every 6.3 weeks. Last sowing by Aug 31 to harvest before frost.

Plant Water Budget

Plant needs
1.5″/week
Rainfall provides
0.5″/week
You supply
1.0″/week
Watering frequency 2-3 times/week
Season total 2,121 gal / 100 sq ft

Monthly Watering Guide for Malabar Spinach

Malabar Spinach needs approximately 1.5 inches of water per week (6.5" per month). Here's how your county's rainfall compares month by month.

Month Malabar Spinach Needs Rainfall You Supplement Action
Jan 0.6" 0" ❄️ Dormant
Feb 0.8" 0" ❄️ Dormant
Mar 6.5" 1.7" 4.8" 🚿 Regular watering
Apr 6.5" 2.7" 3.8" 🚿 Regular watering
May 6.5" 3.2" 3.3" 🚿 Regular watering
Jun 6.5" 4" 2.5" 💧 Light watering
Jul 6.5" 3.1" 3.4" 🚿 Regular watering
Aug 6.5" 3.2" 3.3" 🚿 Regular watering
Sep 6.5" 2.1" 4.4" 🚿 Regular watering
Oct 6.5" 1.6" 4.9" 🚿 Regular watering
Nov 6.5" 0.8" 5.7" 🚿 Regular watering
Dec 0.7" 0" ❄️ Dormant

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

Malabar 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.

Malabar Spinach needs ~1,141 GDD — county provides 4,161 GDD Excellent fit

Malabar Spinach Planting Timeline — Jefferson County, OK

Malabar Spinach Planting Calendar

Activity When Date Range
Start Indoors February 5 Feb 5 – Feb 19
Transplant Outdoors April 9 Apr 9 – Apr 23
Direct Sow April 2 Apr 2 – Apr 23
Harvest June 4 Jun 4 – Jul 2

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1.5"/week · 2-3 times/week

📅 Days to Maturity

55–70 days

🧪 Soil pH

Needs 6–7.5 · Your soil: ideal

🗺️ USDA Zone

Zone 8a

📆 Growing Season

228 days in Jefferson County

Growing Tips for Malabar Spinach in Jefferson County

Direct sow Malabar Spinach outdoors after March 26 in Jefferson County when soil has warmed and frost danger has passed.

Jefferson County receives only 25" of rain annually. Malabar Spinach needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.

General growing tips

Direct sow after last frost or start indoors. Provide a trellis for the vigorous vines. Harvest young leaves regularly; older leaves become mucilaginous when cooked.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Malabar Spinach in Jefferson County, OK?

Jefferson County is in Zone 8a with an average last frost of March 26. Plan your Malabar Spinach planting based on this frost date — see the calendar above for exact timing.

What planting zone is Jefferson County, OK?

Jefferson County, Oklahoma is in USDA Hardiness Zone 8a. The average last spring frost is March 26 and first fall frost is November 9.

🌱

Your Jefferson County Garden Planner — Free

A 24-page printable planner built for Jefferson County (Zone 8a). 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, OK. 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.