A simple gardening experiment is getting attention online after one Reddit user planted a sprouted grocery-store potato and watched it take off.

The post also raised a question many beginner gardeners have: When is a potato actually ready to harvest?

What happened?

In the post on r/gardening, a user shared a photo of a potato plant taking off after being planted from a sprouted store-bought potato. 

The original poster asked how they would know the potato was ready, and the most common response was straightforward — probably later than they think. Several commenters on the thread said full-size potatoes are generally ready later in the season, once the tops have yellowed or browned and died back.

Other gardeners offered a bit more detail. 

One said they like harvesting smaller "young potatoes" around the time the plant flowers, while another said to wait until the greenery had fully died and then leave the potatoes underground for another week or two. A few commenters in the thread also suggested piling more soil around the plant's base as it gets taller.

Why does it matter?

The post shows how approachable growing food can be. In this case, a sprouted potato that might have ended up in the trash became a productive garden plant.

That kind of low-cost starting point can make a difference for households looking to stretch their grocery budgets. Even a modest harvest can help reduce produce spending, and homegrown food often tastes better since it can be picked at peak ripeness instead of being shipped and stored. One commenter said one piece of potato produced several more.

There are added benefits as well. Gardening can help people stay active, spend more time outside, and build a calming routine that supports mental well-being. For beginners, potatoes can also be an encouraging crop because they grow fast enough to stay interesting while still teaching patience and observation.

If you're interested in starting your own edible garden, here is a guide to growing your own food.

What can I do?

If you want larger, fully mature potatoes, many Reddit commenters said to wait until most or all of the plant had died back. Yellowing leaves and stems are usually a sign that the tubers underground are finishing their growth. If you prefer tender new potatoes, some gardeners said they harvest earlier, around flowering time.

Commenters also suggested "hilling," which means piling more soil around the stems as the plant gets taller. That can help support the plant and give developing potatoes a more protected space underground. One user recommended doing that every few inches of growth.

For anyone trying this at home, the appeal is simple: Start with what you already have, learn as you go, and turn kitchen scraps into food. If weeds or pests become a problem, check out these guides for tips on controlling weeds without chemicals and controlling pests without chemicals.

As one commenter put it, "Potatoes are the opposite of people. When they die it's time to dig them up." Another summed up the reward this way: "One bit of potato made about 7 little ones. Yes, they tasted amazing."

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