When to Plant Tomatoes in Zone 6

Tomato timing in zone 6

Most of zone 6 sees its last spring frost between April 25 and May 8, with a typical date of May 1. Tomatoes are killed by frost, so if your last frost comes late, plant toward the end of the window. The tool above uses the weather station closest to your ZIP code.

Why tomatoes wait for warm weather

Tomatoes are warm-season plants. A frost kills them, and cold soil and cold nights stall their growth even without frost. They do best once the soil is at least 65 °F and the air at least 60 °F, which is why transplants go out one to two weeks after the last spring frost rather than on the frost date itself.

Best tomato varieties for zone 6

Zone 6 has a long enough summer for almost any tomato, so choose by how you’ll use them:

• Cherry tomatoes ripen first, about 50 days after transplanting, and keep producing until frost.
• Early and mid-season slicers (about 60–75 days) give you tomatoes by midsummer.
• Full-season and heirloom slicers (85 days or more) have time to ripen here, but start them indoors on time.
• Paste tomatoes are best for sauce and canning. Determinate paste types ripen most of their crop over a couple of weeks.

If diseases have been a problem in your garden, look for disease-resistant varieties.

How to plant tomatoes

1. Start seeds indoors about six to eight weeks before your transplant date, in soil kept at 60–70 °F.
2. Harden off the seedlings by setting them outside for a few hours a day, increasing the time over several days.
3. Plant deep. Set plants at the depth of their first leaves. Leggy seedlings can be laid at an angle, with only the top 5–6 inches above the soil.
4. Space them out: 1–3 feet apart, or 12–18 inches for staked indeterminate plants.
5. Add support right away. Use 6-foot stakes for indeterminate tomatoes and cages 4–5 feet tall for determinate ones.
6. Feed lightly at planting with a starter fertilizer, and again with nitrogen once the first fruit sets.

Zone 6 tomato tips

• Water deeply and evenly. Soak the soil every 7–10 days rather than sprinkling often. Uneven watering causes blossom end rot and cracked fruit.
• Water the soil, not the leaves. Avoid sprinkling late in the day, when wet leaves stay damp overnight.
• Prune indeterminate plants. Keep one to four main stems and pinch off side shoots every 7–10 days.
• Top the plants in late summer. About a month before your first frost, cut off the tips of indeterminate vines so the plant ripens the fruit it already has.
• Rotate. Don’t plant tomatoes where tomatoes, peppers, potatoes or eggplant grew in the last three or four years.

Harvesting tomatoes

Pick tomatoes when they are fully colored, or when they are 60–90% colored and let them finish ripening indoors. Keep ripening and ripe tomatoes at 50–55 °F and out of the refrigerator, which ruins their flavor. When a frost is forecast, pick mature green fruit (the inside is filled with gel) and ripen it at 65–70 °F.

Tomato planting dates in nearby zones

• Zone 5May 15 – May 22
• Zone 7April 24 – May 1

See dates for every zone on the tomatoes planting guide, or build a full schedule with the planting calendar.