You can grow a new tomato plant from a cutting of an existing one in four to six weeks

Cloning means taking a cutting from a healthy tomato plant and rooting it to create an identical copy. The new plant will have the same variety, flavor, and growing habits as the parent. You cut a 4- to 6-inch stem tip from new growth, remove the lower leaves, place it in water or soil, and wait for roots to form. Most cuttings root in two to three weeks indoors under basic conditions—no special equipment needed.

This method works year-round indoors and is faster than starting from seed. It's especially useful if you have a tomato variety you love and want to keep growing it without buying new seeds each season, or if you want to preserve a plant before frost kills it in fall.

Key Takeaways

  • Cut a 4- to 6-inch stem from new growth at the tip of a healthy branch, using a clean knife or pruners to avoid crushing the stem.
  • Remove all leaves from the bottom 2 inches of the cutting so they won't sit in water or soil and rot.
  • Place the cutting in a jar of room-temperature water or moist potting soil, and roots will form in two to three weeks.
  • Once roots are at least 1 inch long, transplant the rooted cutting into a small pot with potting soil and treat it like a seedling.
  • The new plant will be ready to move outdoors or into a larger container four to six weeks after you take the cutting.

Choose the right stem and take the cutting correctly

Select a healthy stem from the top 6 inches of the plant—this new growth roots faster than woody, mature stems. The stem should be soft enough to bend slightly without snapping, and it should have at least three sets of leaves. Using a clean, sharp knife or pruning shears, cut at a 45-degree angle just below a leaf node (the bump where a leaf attaches to the stem). A 45-degree cut gives more surface area for roots to form.

Work quickly after cutting. The exposed stem dries out fast, so place the cutting in a cup of water when ready if you're not rooting it right away. Take cuttings in the morning when the plant is most hydrated—afternoon cuttings wilt more easily.

Prepare the cutting by removing lower leaves

Strip all leaves from the bottom 2 inches of the stem using your fingers or a clean knife. These lower leaves will sit in water or soil and rot, which invites fungal disease and slows rooting. Leave the top leaves intact—the plant needs them to photosynthesize and power root growth. If the top leaves are very large, you can pinch off the top quarter of each one to reduce water loss while roots are forming.

Inspect the cutting for damage or disease. If the stem is bruised, cut off the damaged section with a clean knife. Do not use cuttings from plants showing spots, yellowing, or wilting—disease spreads to the new plant.

Root the cutting in water

Fill a clear glass or jar with room-temperature tap water. Place the cutting so the bottom 1 to 2 inches sit submerged and the leaves stay above the water line. Set the jar in bright, indirect light—a windowsill works well. Change the water every three to four days to prevent bacterial growth and keep oxygen levels high.

Roots usually appear in 10 to 14 days as small white bumps at the base of the stem. By day 21, you should see roots at least 1 inch long. Do not wait longer than three to four weeks—roots grown in water are fragile and struggle when moved to soil. Once roots reach 1 inch, transplant the cutting into potting soil.

Root the cutting in soil as an alternative

If you prefer to root directly in soil, fill a small pot (2 to 3 inches wide) with moist potting mix. Poke a hole in the soil with your finger, insert the cutting 1 to 2 inches deep, and gently firm the soil around it. Water lightly so the soil is damp but not soggy. Cover the pot with a clear plastic bag or dome to hold humidity—this speeds rooting and prevents wilting.

Place the pot in bright, indirect light and keep the soil consistently moist but not waterlogged. Check daily by touching the soil; water when the top feels dry. Roots form in two to three weeks. You can gently tug the cutting after two weeks—if you feel resistance, roots are forming. Once the cutting shows new leaf growth, roots are established and you can remove the plastic cover.

Transplant the rooted cutting into a larger pot

When roots are 1 inch long (water-rooted cuttings) or new leaves appear (soil-rooted cuttings), move the cutting to a 4- to 6-inch pot filled with potting soil. Bury the stem so the lowest leaves sit just above the soil surface. Water gently and place the pot in bright light—a sunny windowsill or grow light works well. Keep the soil moist for the first week, then water when the top inch feels dry.

The young plant will look droopy for a few days as it adjusts to soil. This is normal. After one week, it should perk up and begin growing new leaves. Pinch off the very tip of the stem once the plant has four sets of leaves—this encourages branching and a bushier shape.

Harden off and move the plant outdoors

Four to six weeks after taking the cutting, the plant should be 6 to 8 inches tall with a strong root system. Before moving it outside, harden it off by gradually exposing it to outdoor conditions over seven to ten days. Start by placing the pot in a sheltered spot outdoors for one to two hours, then bring it back inside. Each day, increase the time outside by one to two hours and expose it to more direct sun. By day seven to ten, the plant can stay outside overnight if temperatures stay above 50°F.

Once hardened off, transplant the clone into a garden bed or larger container (at least 5 gallons) with potting soil mixed with compost. Space plants 24 to 36 inches apart. Water deeply and stake or cage the plant for support as it grows. The cloned plant will flower and produce fruit on the same schedule as the parent plant.

Common mistakes to avoid

The most common error is taking cuttings from old, woody growth instead of new stem tips. Woody stems root slowly or not at all. Another mistake is leaving lower leaves on the cutting—they rot and introduce disease before roots form. Overwatering soil-rooted cuttings causes stem rot; the soil should be moist, not soggy. Underwatering wilts the cutting before roots form, so check daily.

Do not move the cutting to soil too early. Water-rooted cuttings need roots at least 1 inch long before transplanting, or they will collapse in soil. Finally, do not skip hardening off. A cutting grown indoors under lights is tender and will wilt or sunburn if moved directly outside. The gradual exposure toughens the plant and prevents shock.

Frequently Asked Questions

Can I clone a tomato plant that's diseased or stressed?

No. Disease spreads to the new plant, and stressed plants produce weak cuttings that root poorly or die. Always take cuttings from healthy, vigorous plants. If your plant is diseased, treat it first or start fresh from seed.

How many cuttings can I take from one plant?

You can take several cuttings from a healthy plant without harming it. Remove no more than one-third of the plant's growth at a time. If you need many cuttings, space them out over two to three weeks so the plant can recover between harvests.

What temperature do cuttings need to root?

Tomato cuttings root best between 65°F and 75°F. They will root in cooler temperatures but more slowly. Avoid temperatures below 55°F or above 85°F, which slow or stop rooting. A warm windowsill or heated propagation mat works well.

Can I use rooting hormone to speed up the process?

Rooting hormone (powder or liquid) can help, but it's not necessary for tomato cuttings—they root easily without it. If you use it, follow the label directions and dip only the cut end of the stem. Excess hormone can damage the cutting.

Will the cloned plant produce fruit the same year?

If you take the cutting early in spring and root it indoors, the plant will be large enough to flower and fruit by mid-summer. Cuttings taken in late summer or fall will grow indoors over winter and fruit the following season.