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When to Plant Cucumber in Johnson County, TN

Johnson County, Tennessee Zone 7a May

Your May gardening checklist

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

Avg. last frost April 14
Avg. first frost October 22
Soil temp (4") 64°F
Watering Moderate
Pest pressure Low
Daylight 13.9 hrs
  1. Get cucumber seeds going inside

    Bottom-water once the first true leaves appear — it keeps stems dry and knocks back damping-off.

June will be here before you know it — start on
  • First harvests: cucumber

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Cucumbers are a warm-season vine crop available in slicing and pickling varieties. They are prolific producers when given warmth, moisture, and a trellis to climb.

Johnson County, Tennessee is in USDA Zone 7a. The average last spring frost is April 14 and the first fall frost is October 22, giving you a growing season of approximately 191 days.

At an elevation of 404 feet, Johnson County receives approximately 43.2 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86°F, providing good warmth for Cucumber during the growing season.

Johnson County, TN (Zone 7a) Moderate season
191 days
Last Spring Frost April 14
191 growing days
First Fall Frost October 22

Johnson County Soil Profile

Soil Type

Silt Loam

Soil pH

5.7-7.1

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (65 days to spare)
Start indoors: Mar 12 Transplant: Apr 23 🍅 Harvest: Jun 18 – Aug 13
Recommended (50%) ✓ Fits season (65 days to spare)
Start indoors: Mar 17 Transplant: Apr 28 🍅 Harvest: Jun 23 – Aug 18
Safe Start (90%) ✓ Fits season (58 days to spare)
Start indoors: Apr 6 Transplant: May 18 🍅 Harvest: Jul 13 – Sep 7

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 Johnson County

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

Soil pH

Your soil pH (5.7–7.1) overlaps with Cucumber's range (6.0–7.0), though not a perfect match.

Soil Texture

The silt loam soil in Johnson County is excellent for Cucumber — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (2.5%). Annual compost additions will help Cucumber.

How to Plant Cucumber

0.5"
Planting Depth
24"
Between Plants
48"
Between Rows

Succession Planting Cucumber

4
successive plantings in your 191-day season

Sow every 5.7 weeks. Last sowing by Aug 13 to harvest before frost.

Plant Water Budget

Plant needs
1.5″/week
Rainfall provides
1.0″/week
You supply
0.7″/week
Watering frequency 1-2 times/week
Season total 1,122 gal / 100 sq ft
Drought risk

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

Monthly Watering Guide for Cucumber

Cucumber 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 Cucumber Needs Rainfall You Supplement Action
Jan 4" 0" ❄️ Dormant
Feb 3.4" 0" ❄️ Dormant
Mar 4.5" 0" ❄️ Dormant
Apr 6.5" 3.2" 3.3" 🚿 Regular watering
May 6.5" 3.7" 2.8" 💧 Light watering
Jun 6.5" 3.4" 3.1" 💧 Light watering
Jul 6.5" 4" 2.5" 💧 Light watering
Aug 6.5" 4.2" 2.3" 💧 Light watering
Sep 6.5" 3.5" 3" 💧 Light watering
Oct 6.5" 2.8" 3.7" 🚿 Regular watering
Nov 3" 0" ❄️ Dormant
Dec 3.7" 0" ❄️ Dormant

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

Cucumber 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.

Cucumber needs ~870 GDD — county provides 2,769 GDD Excellent fit

Cucumber Planting Timeline — Johnson County, TN

Cucumber Planting Calendar

Activity When Date Range
Start Indoors March 17 Mar 17 – Mar 31
Transplant Outdoors April 28 Apr 28 – May 12
Direct Sow April 21 Apr 21 – May 12
Harvest June 23 Jun 23 – Aug 18

Plant 0.5" deep · 24" apart · Rows 48" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1.5"/week · 1-2 times/week

📅 Days to Maturity

50–70 days

🧪 Soil pH

Needs 6–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 7a

📆 Growing Season

191 days in Johnson County

Growing Tips for Cucumber in Johnson County

Direct sow Cucumber outdoors after April 14 in Johnson County when soil has warmed and frost danger has passed.

Common pests for Cucumber in this region include squash vine borer and cucumber beetles. Use row covers early in the season and inspect plants weekly.

General growing tips

Direct sow after last frost or start indoors 3 weeks early. Provide a trellis for vining types to save space and improve air circulation. Harvest frequently to encourage production.

Companion Planting

Good Companions

Avoid Planting Near

  • Potatoes
  • Sage

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Cucumber in Johnson County, TN?

Johnson County is in Zone 7a with an average last frost of April 14. Plan your Cucumber planting based on this frost date — see the calendar above for exact timing.

What planting zone is Johnson County, TN?

Johnson County, Tennessee is in USDA Hardiness Zone 7a. The average last spring frost is April 14 and first fall frost is October 22.

🌱

Your Johnson County Garden Planner — Free

A 24-page printable planner built for Johnson County (Zone 7a). 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 Johnson County, TN. 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.