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When to Plant Heirloom Tomato in Madison, Wisconsin (53708)

Location

Madison, Wisconsin

ZIP Code

53708

USDA Zone

5b

Last Frost

Saturday, April 25, 2026

📅 Your 2026 Planting Dates

Start Seeds Indoors

Saturday, March 14, 2026

Transplant Outdoors

Saturday, May 9, 2026

Based on last frost Saturday, April 25, 2026 · Zone 5b

Pro tip: Start Heirloom Tomato seeds indoors 6 weeks before your last frost date, then transplant outdoors around Saturday, May 9, 2026.

🌿 Plant Details

Scientific Name Solanum lycopersicum
Days to Maturity 80 days
Mature Height 48-84"
Spread 24"
Type Indeterminate
Fruit Size Variable (2-32 oz depending on variety)

☀️ Growing Requirements

☀️

Sun

Full Sun (6-8 hours)

💧

Water

Regular (1-2 inches/week)

↔️

Spacing

30" apart

🌱

Planting Depth

0.25" deep

Seeds typically germinate in 5-10 days

Ready to Plant Heirloom Tomato in Madison?

Get your seeds now so they're ready by Saturday, March 14, 2026.

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🤝 Good Companions

BasilCarrotParsleyMarigoldBorage

⚠️ Avoid Planting Near

BrassicasFennelCornKohlrabi
🤝

Full Companion Planting Guide for Heirloom Tomato

See which plants help Heirloom Tomato thrive, which to keep away, and raised bed layout tips →

🛠️ Supplies You'll Need

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Common Heirloom Tomato Varieties

Popular cultivars to look for at your local nursery or seed supplier.

Brandywine

heirloom 80d

Large, pinkish-red heirloom prized for its complex, rich flavor — a benchmark for taste.

Cherokee Purple

heirloom 80d

Deep mahogany-purple with a smoky-sweet flavor profile and striking appearance.

Green Zebra

heirloom 78d

Striped green-yellow tomato with tangy, bright flavor — stays green when ripe.

Mortgage Lifter

heirloom 85d

Massive 2+ lb fruits bred by a backyard gardener in the 1930s; famously mild and sweet.

Aunt Ruby's German Green

heirloom 80d

Large green-when-ripe beefsteak with a complex, spicy-fruity flavor.

🌾 Seed Saving Guide

🟢 Easy
✅ Open-pollinated — seeds grow true to parent

When to Harvest Seed

Let fruit ripen fully and slightly past peak on the vine before scooping seeds.

Processing

Scoop seeds into water, ferment 2–3 days, rinse well, dry flat on a non-stick surface for 1 week.

Seed Viability

Up to 4 years when stored cool, dark, and dry.

Pro Tip

Heirloom tomatoes are open-pollinated and grow true from seed. Separate varieties by 25 feet to prevent crossing.

🪴

Raised Bed Planting Guides

A 4×8 bed fits 5 plants of Heirloom Tomato. See plant counts, spacing grids, and companion pairings for every bed size →

Frequently Asked Questions

When should I plant Heirloom Tomato in Madison, Wisconsin? +

In Madison (Zone 5b), start Heirloom Tomato seeds indoors around Saturday, March 14, 2026 and transplant outdoors around Saturday, May 9, 2026.

What is the last frost date for Madison, Wisconsin? +

The average last spring frost date for Madison, Wisconsin (ZIP 53708) is around Saturday, April 25, 2026. This is based on NOAA climate normals for USDA Zone 5b.

How long does Heirloom Tomato take to grow? +

Heirloom Tomato typically matures in about 80 days from transplanting. In Madison, that means you can expect harvest around Saturday, May 9, 2026 plus 80 days.

Should I start Heirloom Tomato indoors or direct sow in Wisconsin? +

Heirloom Tomato should be started indoors 6 weeks before your last frost date. In Madison, that means starting around Saturday, March 14, 2026.

Other Plants for Madison

Growing Heirloom Tomato in Zone 5b

Heirloom Tomato (Solanum lycopersicum) is a popular garden vegetable. In Madison, Wisconsin, which is in USDA Hardiness Zone 5b, you should start seeds indoors around Saturday, March 14, 2026.

Your average last frost date is Saturday, April 25, 2026. Plan to transplant your Heirloom Tomato seedlings outdoors around Saturday, May 9, 2026, about 2 weeks after your last frost date.