Upcycle small food containers or even newspaper for starting seeds indoors

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This article was published 04/03/2025 (595 days ago), so information in it may no longer be current.

If you’re planning to start seeds indoors this season, you likely know you’ll need a growing medium (packaged, sterile seed-starting mix is ideal), a sunny windowsill or grow lights and, of course, seeds. But have you given thought to what containers you’ll use?

You might be planning to buy rimmed trays, peat pots or compartmentalized plastic flats, but they’re not your only options. With a bit of imagination, you can easily upcycle items you already have while keeping trash out of the landfill and your money in your wallet.

Try some small food containers

If you have a coffee maker that uses K-Cup-style plastic pods, don’t discard them after brewing. Instead, peel off their foil covers, dump out the used coffee grinds and remove the paper filters underneath. The pods are the perfect size for starting seedlings, and can be washed, disinfected and reused from year to year. You’ll notice the machine even poked a hole in each pod’s bottom for drainage.

Most other small plastic food containers, such as single-serving yogurt cups, clamshell-type salad packages or egg cartons, are also well-suited for starting seeds — as long as you’ve poked holes in their bottoms to allow excess water to drain.

Newspaper or cardboard work well, too

You can even make seed pots from sheets of newspaper. Much of today’s newsprint uses soy-based ink, which is generally considered non-toxic, suitable even for starting edibles.

Here’s how: Fold a newspaper page in half lengthwise, then fold it a second time to achieve a long strip. Next, place a tomato paste can, which is the perfect size for a seed pot, along one edge of the newspaper, a couple of inches from the bottom. Then, roll the newspaper tightly around the can to form a cylinder.

Fold the excess newspaper in at the base of the can, set the wrapped can right-side-up and press it firmly against a flat surface like a table or counter to fortify the bottom of your new pot. If necessary, use a small piece of tape to secure the bottom.

Remove the can and voila! You’ve made a free starter home for your seedlings.

Instead of watering conventionally, which would risk soaking the newspaper, keep the soil surface moist with a spray bottle.

Or cut four 1-inch slits, evenly spaced, around one end of a toilet paper roll. Fold in the resulting tabs and tape them in place to create a solid bottom for your pot.

Why use such small pots?

As their names imply, seed-starting containers are intended only for the first phase of seedlings’ lives. When they outgrow those first pots, sprouted seedlings will need to be moved into larger containers to accommodate their expanding root systems.

Handle fragile seedling roots gingerly when repotting to minimize the odds of transplant shock (newspaper and toilet paper roll pots are biodegradable, so there is no need to remove plants from them when upsizing containers; just plant the whole pot into a larger one.)

You might be wondering why you shouldn’t just start seeds in larger containers from the outset. It’s a logical question with an equally logical answer: Larger pots require a larger amount of potting mix, which would hold more water than a seedling’s fledgling roots can absorb. That excess moisture would place seedlings at risk of root rot, an often-fatal plant disease caused by excess moisture.

It’s also cost-effective to go smaller. Sterile seed-starting mix is more expensive than ordinary potting mix, and you’ll use considerably less in a smaller container than in a larger one. When repotting young plants, you can use ordinary potting mix in their step-up containers, but never use ordinary garden soil; it’s too dense and may harbor pests or pathogens.

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Jessica Damiano writes weekly gardening columns for the AP and publishes the award-winning Weekly Dirt Newsletter. You can sign up here for weekly gardening tips and advice.

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