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When to Plant Tomatoes in Tompkins County, NY

Tomatoes

Tomatoes are the most popular home garden crop, available in thousands of varieties from tiny cherries to massive beefsteaks. They are warm-season plants needing full sun.

Tompkins County, New York is in USDA Zone 6a. The average last spring frost is May 10 and the first fall frost is October 11, giving you a growing season of approximately 154 days.

At an elevation of 309 feet, Tompkins County receives approximately 40.5 inches of rainfall annually with predominantly silt loam soil. Summer highs average 87°F, providing good warmth for Tomatoes during the growing season.

Tompkins County, NY (Zone 6a) Moderate season
154 days
Last Spring Frost May 10
154 growing days
First Fall Frost October 11

Tompkins County Soil Profile

Soil Type

Silt Loam

Soil pH

5.2-6.4

Drainage

Well Drained

How Much Tomatoes to Grow

10-15 lbs
Average yield per plant
3
Plants per person
6 sq ft
Space per person

For a family of 4, plant approximately 12 tomatoes plants in about 24 sq ft. In Tompkins County's 154-day season, you'll have plenty of time for a full harvest. Plan your garden layout →

Monthly Watering Guide for Tomatoes

Tomatoes needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Tomatoes Needs Rainfall You Supplement Action
Jan 3.2" 0" ❄️ Dormant
Feb 2.8" 0" ❄️ Dormant
Mar 3.4" 0" ❄️ Dormant
Apr 3.3" 0" ❄️ Dormant
May 4.3" 3.3" 1" 💧 Light watering
Jun 4.3" 3.8" 0.5" 💧 Light watering
Jul 4.3" 4.4" 0" ✅ Rainfall sufficient
Aug 4.3" 3.5" 0.8" 💧 Light watering
Sep 4.3" 3.8" 0.5" 💧 Light watering
Oct 4.3" 2.9" 1.4" 💧 Light watering
Nov 3.5" 0" ❄️ Dormant
Dec 2.6" 0" ❄️ Dormant

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

Tomatoes Planting Timeline — Tompkins County, NY

Tomatoes Planting Calendar

Activity When Date Range
Start Indoors March 15 Mar 15 – Mar 29
Transplant Outdoors May 24 May 24 – Jun 7
Direct Sow May 17 May 17 – Jun 7
Harvest July 26 Jul 26 – Oct 4

Plant 0.5" deep · 24" apart · Rows 36" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

Moderate — regular watering

📅 Days to Maturity

60–85 days

🧪 Soil pH

Needs 6–7 · Your soil: N/A

🗺️ USDA Zone

Zone 6a

📆 Growing Season

154 days in Tompkins County

Growing Tips for Tompkins County

Start seeds indoors 6-8 weeks before last frost. Bury transplants deep to encourage rooting along the stem. Provide consistent moisture to prevent blossom end rot and cracking.

Companion Planting

Good Companions

Avoid Planting Near

  • Cabbage
  • Fennel
  • Potatoes

Check more plant combinations with our Companion Planting Checker →

🌾 Save Your Own Tomatoes Seeds
Life Cycle Annual
Pollination Self-Pollinating
How to Collect Scoop seeds from ripe fruit; ferment 2-3 days to remove gel coating.
Storage Store airtight; viable 4-6 years at 35°F, under 45% humidity.

Isolate 25 ft between varieties for purity. Use open-pollinated varieties for true-to-type seeds.

Frequently Asked Questions

When should I plant Tomatoes in Tompkins County, NY?

Tompkins County is in Zone 6a with an average last frost of May 10. Plan your Tomatoes planting based on this frost date — see the calendar above for exact timing.

What planting zone is Tompkins County, NY?

Tompkins County, New York is in USDA Hardiness Zone 6a. The average last spring frost is May 10 and first fall frost is October 11.

🌱

Your Tompkins County Garden Planner — Free

A 22-page printable planner built for Tompkins County (Zone 6a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

Instant PDF download. No spam, unsubscribe any time.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Tompkins County, NY. Local conditions may vary. Last updated: June 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.