Root Tomato Suckers for Free Plants This June

Last June I snapped off a fistful of tomato suckers and threw them straight in the compost. I know. I know. It was drizzly and I was tired and I just didn’t feel like dealing with them. Took me another full season to figure out I’d been tossing free tomato plants every single year. The good news is it’s easy to root tomato suckers in about a week, and if you’ve got plants in the ground right now, you’ve already got everything you need.

Rooting tomato suckers sounds fancier than it is. You snap off a piece, stick it in water, wait a week, plant it. That’s pretty much the whole trick. And if you’ve got tomatoes in the ground right now, you’ve got suckers, which means you’ve got free plants just waiting to happen.

Which Suckers to Take

A sucker is the little shoot that grows in the crotch between the main stem and a branch. Left alone, it turns into a whole new vine. Great news for propagation. Slightly annoying news for your tomato cage situation.

For rooting, you want suckers that are 4 to 6 inches long. Smaller than that and they’re too fragile. Bigger and you’re asking the cutting to support more leaves than its nonexistent root system can handle. Snap them off cleanly with your fingers or snip with scissors. Either works fine.

One thing that actually matters: no flowers. If the sucker has already started budding, pinch those off before you try to root it. A cutting that’s busy trying to flower is not busy trying to grow roots. You want all its energy going one direction.

Also worth knowing: suckers from indeterminate varieties root and fruit better than those from determinate types. If your plants are the kind that keep going all season (most heirlooms and most slicers are), you’re in good shape. Check out what to grow in your garden in June if you’re still sorting out what you’ve actually got out there.

The Water Method (Laziest and Also My Favorite)

Strip the leaves off the bottom half of the cutting. Whatever’s going to be underwater needs to go. Drop it in a jar or a glass, fill with room-temperature water, set it on a windowsill with decent indirect light.

That’s it. Growth mindset. (Gardening pun. Sorry.)

Roots usually show up in 7 to 10 days. Sometimes faster. Change the water every couple of days so it stays clear and doesn’t get funky. Once you’ve got a little cluster of white roots an inch or two long, it’s ready to pot up. Don’t wait until they’re six inches long because then transplanting gets weird and you’ll probably snap half of them off anyway. Ask me how I know.

The Potting Mix Method (Slightly More Effort, Similar Results)

Same prep: strip the lower leaves, leave a couple at the top. Stick the cutting a couple inches deep into a cup of damp potting mix. Tamp it gently so it stands up on its own. Put a loose plastic bag over the top to hold in humidity, or just mist it once a day.

Keep it somewhere warm. Tomato cuttings root best around 70 to 75 degrees, which is also just a comfortable room temperature. A south-facing windowsill in June works well. Roots typically form in 10 to 14 days with this method. You won’t see them, but you’ll know it’s working when the cutting stops looking sad and starts looking perky.

Either method works. The water method lets you watch the roots form, which is genuinely satisfying in a nerdy way. The soil method skips one transplanting step. Pick whichever one you’ll actually do.

Why June Is the Right Time

Here’s the part that makes this worth doing. A rooted tomato sucker is genetically identical to the parent plant. Same flavor, same fruit size, same everything. And because it’s already a few weeks of growth ahead of a seed, it catches up fast.

Take a cutting now, in June, and you’ve got a rooted plant by mid-July at the latest. Get it in the ground or a container by late July and it has a real shot at producing fruit before the season winds down. In a cool climate with a longer shoulder season, that window is wider than you’d think.

This is genuinely useful if you lost a plant to something, have an empty spot in a container, or just want to hedge your bets without spending anything. A six-pack of tomato starts from the local nursery isn’t cheap by July. A sucker from your own plant is free and already proven in your exact conditions.

Lettuce be honest: the best plant is the one that costs you nothing. (Okay that one was a stretch, I’ll show myself out.)

If you want to keep the productive streak going later in the year, I wrote about cover crops for winter that are worth thinking about now while you’ve still got time to plan.

One More Thing

Don’t root 12 of these at once unless you actually have places to put 12 tomato plants. I say this from experience. My daughters thought it was the coolest experiment and we ended up with plants on every surface of the kitchen and a very patient spouse. Two or three cuttings is probably the move for most people.

But do try at least one. It takes five minutes and costs nothing, and watching roots appear in a mason jar on your windowsill is one of the weirder small pleasures of gardening.

Photo by Andrea Scully on Unsplash