Heirloom Tomatoes: Care and Growing Guide
Heirloom tomatoes need 70–80 days from transplant. This guide covers the best US varieties, planting times by zone, and flavor profiles by type.
Key takeaways
- Heirloom tomatoes are open-pollinated varieties that breed true from saved seed—you can replant saved seeds year after year with identical results
- Most heirloom varieties are indeterminate, growing 6–8 feet tall and requiring stakes or cages taller than standard 3-foot wire cages
- Heirlooms take 5–10 days longer to ripen than hybrid varieties—expect 70–85 days from transplant depending on the cultivar
- Cracking is the most common heirloom problem, caused by uneven watering; mulching and consistent irrigation reduces cracking by 60–70%
- Cherokee Purple, Brandywine, and German Johnson are the three most planted heirloom varieties in US home gardens
What makes a tomato an heirloom
Heirloom tomatoes are open-pollinated varieties grown continuously for at least 50 years. Seeds saved from each harvest grow into plants identical to the parent—the defining feature that separates heirlooms from modern hybrids.
No single agency certifies “heirloom” status. Most growers use 50 years as the threshold. Some seed banks, including Seed Savers Exchange in Decorah, Iowa, extend that to pre-1951 varieties.
The practical difference for home gardeners is seed saving. You can harvest seeds from a ripe heirloom fruit, dry them, and replant next spring. The plants will produce the same tomato, year after year. This is possible because heirlooms pollinate themselves without crossing with other varieties. Hybrid tomatoes, by contrast, are crosses between two parent lines. Their seeds don’t produce offspring that match the original fruit.
Flavor is the other difference. Heirlooms have more diverse flavor profiles than most hybrids—ranging from sweet and low-acid to deeply savory. This comes from a wider genetic base developed over decades of selection by different growers. Hybrid tomatoes were selected primarily for yield, uniformity, and shelf life, qualities that matter for commercial production but often at the cost of flavor depth.
Best heirloom tomato varieties for US gardens
Not all heirlooms perform equally across US climates. Choosing a variety matched to your zone is more important with heirlooms than with hybrids, which were bred with broader adaptability in mind.
| Variety | Color | Days to maturity | Best zones | Flavor profile |
|---|---|---|---|---|
| Brandywine (Sudduth’s Strain) | Pink-red | 78–80 days | Zones 5–8 | Sweet, rich, low acid |
| Cherokee Purple | Dark purple-red | 72–80 days | Zones 5–9 | Complex, smoky, full-bodied |
| German Johnson | Pink | 75–80 days | Zones 6–9 | Mild, sweet, very low acid |
| Mortgage Lifter | Pink | 80–85 days | Zones 5–8 | Sweet, meaty, mild flavor |
| Amish Paste | Red | 72–80 days | Zones 5–8 | Rich, dense; best for sauce |
| Black Krim | Dark red-brown | 69–80 days | Zones 5–9 | Earthy, salty, complex |
| Stupice | Red | 60–65 days | Zones 3–7 | Tangy; best for short seasons |
| Brandywine Black | Dark purple | 78–85 days | Zones 5–8 | Sweet-smoky; high anthocyanins |
For specifics on individual varieties, see our guides for Cherokee Purple tomato, Mortgage Lifter tomato, and Pink Brandywine tomato.
When to plant heirloom tomatoes by zone
Heirloom tomatoes are warm-season crops. Cold soil kills them and cool nights below 55°F slow fruit set. Transplant heirlooms into the garden 2 weeks after your last frost date, when soil temperatures have reached 60°F.
| USDA Zone | Last frost | Transplant date | First harvest (80-day variety) |
|---|---|---|---|
| Zone 4 | May 15–31 | June 1–14 | August 20–Sept 5 |
| Zone 5 | April 30–May 15 | May 15–June 1 | August 3–August 20 |
| Zone 6 | April 15–30 | May 1–15 | July 20–August 3 |
| Zone 7 | March 30–April 15 | April 15–May 1 | July 3–July 20 |
| Zone 8 | February 28–March 15 | March 15–April 1 | June 3–June 20 |
| Zone 9 | February 1–15 | February 15–March 1 | May 5–May 22 |
In Zone 9 and warmer, heirloom tomatoes face summer heat stress once temperatures exceed 95°F consistently. Many gardeners in these zones plant in late winter for an early summer harvest, then plant a second crop in late July for fall harvest.
For direct-sowing from seed, start heirloom tomatoes 6–8 weeks before transplant date indoors. For Zone 6, that means starting seeds in mid-March for a May transplant. See our guide to growing tomatoes from seeds for full indoor starting instructions.
Soil and site requirements
Heirloom tomatoes perform best in:
Sun: 8+ hours of direct sun daily. Fewer than 6 hours significantly reduces yield. South- or west-facing walls radiate heat that helps in northern zones.
Soil pH: 6.0–6.8. Outside this range, nutrient uptake problems develop even with adequate fertilization. Test soil before planting if you haven’t grown tomatoes in a given bed before.
Drainage: Well-drained soil is non-negotiable. Heirlooms sitting in waterlogged soil develop root rot within days. Raised beds eliminate drainage concerns in heavy clay soils.
Organic matter: Heirloom tomatoes are heavy feeders. Incorporate 2–3 inches of compost into the top 12 inches of soil before planting. This provides slow-release nutrition and improves water retention.
Rotation: Don’t plant tomatoes in the same spot two years in a row. A 3-year rotation away from tomatoes, peppers, and eggplants (all in the nightshade family) reduces soilborne disease pressure significantly.
Planting depth and spacing
Heirloom tomatoes root from buried stems. Plant them deep—bury the stem up to the lowest set of healthy leaves. A transplant placed 6 inches deeper than it was growing in its pot will develop roots along the entire buried stem, producing a more anchored plant with better drought tolerance.
Spacing: Most indeterminate heirlooms need 24–36 inches between plants in rows 4 feet apart. Crowded plants develop air circulation problems that lead to early blight and Septoria leaf spot. For more on spacing decisions, see our guide to how far apart to plant tomatoes.
Staking and support
Most heirloom varieties are indeterminate—they grow continuously until frost and regularly reach 6–8 feet. Standard 3-foot wire tomato cages are undersized for most heirlooms and collapse under the weight of a loaded plant.
Better options:
Tall metal stakes or conduit: Drive 6-foot metal conduit pipes or rebar 12 inches into the ground next to each plant. Tie the main stem every 8–10 inches with soft plant tape or strips of old t-shirt.
Florida weave: Space stakes between every two plants and weave twine in a figure-8 pattern around the stake and the plants at 6-inch height increments. This method supports multiple plants efficiently.
Tall wire cages: 5-foot folded concrete reinforcing wire cages (with 6-inch grid squares so you can reach inside to harvest) outperform standard tomato cages. They last 10+ years.
For more support structure ideas, see our tomato trellis ideas guide and our DIY tomato trellis guide.
Watering heirloom tomatoes
Heirloom tomatoes need consistent moisture more than frequent moisture. Aim for 1–1.5 inches of water per week, applied at the base, with no large gaps in between.
Irregular watering is the primary cause of blossom end rot and fruit cracking—two problems heirlooms are more prone to than modern hybrids. After a dry period, rapid water uptake causes cell expansion that splits the fruit skin.
Mulch is the most effective tool for moderating soil moisture. Apply 2–3 inches of straw, wood chips, or shredded leaves around plants, keeping mulch 3–4 inches away from the main stem. Mulch reduces soil moisture variation between waterings by 60–70%.
Drip irrigation delivers water directly to the root zone and is more consistent than overhead watering. Even a soaker hose on a timer significantly reduces cracking compared to hand-watering.
For more on fertilizing, see our tomato fertilizer guide. For diagnosing leaf problems, our yellow leaves on tomato plants guide covers the most common causes.
Common heirloom tomato problems
Cracking: Caused by uneven watering. Prevent with mulch and consistent irrigation. Once a fruit cracks, harvest immediately and use it fresh.
Blossom end rot: Black leathery patches on the bottom of fruit. Caused by calcium uptake failure, usually from uneven watering or root damage. Correct by mulching and maintaining consistent soil moisture. For a full diagnosis guide, see our blossom end rot guide.
Early blight and Septoria leaf spot: Fungal diseases that start on lower leaves and move up the plant. Remove affected leaves immediately. Avoid overhead watering. Space plants to allow air circulation.
Sluggish ripening in late summer: Heirlooms stop ripening when temperatures exceed 95°F (fruit set fails) or drop below 55°F at night (cold slows ripening). In late summer heat, fruit set resumes once temperatures drop in fall.
Catfacing: Distorted, scarred fruit, most common in Brandywine. Caused by cold temperatures during fruit set (below 55°F at night). Plant later in the season and it resolves naturally.
Harvesting and saving seeds
Harvest heirloom tomatoes when they reach full color and yield to gentle pressure. Don’t wait for them to soften significantly—heirlooms at peak flavor are firm but not hard. Overripe heirlooms lose their flavor complexity quickly.
Most heirlooms taste best at room temperature. Refrigerating tomatoes below 55°F destroys volatile flavor compounds. Store harvested tomatoes stem side down on the counter and use within 5–7 days.
Saving seeds: To save seeds, scoop seeds and gel from a fully ripe fruit into a jar of water. Let ferment at room temperature for 2–3 days, stirring daily. Good seeds sink; hollow seeds and debris float. Drain, rinse thoroughly, and dry on a paper plate for 2 weeks. Store in a cool, dry place—properly dried heirloom seeds remain viable for 4–6 years.
For companion planting options that improve yield and reduce pest pressure, see our tomato companion plants guide and our tomato plants overview.
Sarah Mitchell is a Master Gardener and garden writer based in the Pacific Northwest. She has been growing food and flowers for over 15 years across USDA zones 7 and 8.