The Kratky Method: The Easiest Hydroponic System For Beginners

The Kratky Method is the simplest, most hands-off method for growing plants hydroponically. Epic Gardening founder Kevin Espiritu explains how to set up and use these systems.

Written by Kevin Espiritu Horticulture review by Sarah Jay Last updated: June 5, 2025 | 3 min read

A close-up shot of several jars, turned into DIY hydroponics for developing plants, showcasing the kratky Method

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Although I already consider hydroponics one of the most fascinating, straightforward, and rewarding gardening methods, what continues to surprise me is just how much innovation is constantly happening in the field. There are so many types of hydroponic systems out there—and they seem limited only by our imagination.

Not long ago, I was looking for new ways to experiment with my deep water culture setups, including building a super simple hydroponics project for kids. I wanted something easy to assemble, yet still capable of growing a healthy plant.

Enter the Kratky method. This is one of the easiest hydroponic systems out there, making it a great option for beginners. If you want to give it a try, you’re in the right place.

What is the Kratky Method?

A close-up shot of a hydroponic system including a jar and a developing plant — The system involves growing plants without soil with few moving parts.

Because hydroponics grows plants without soil, there are usually quite a few moving parts involved: pumps, wicks, airstones, and the electricity to power them all. Don’t get me wrong, that’s part of what I love about hydroponics. But sometimes, it’s nice to just keep things simple.

That’s where the Kratky method really shines. It’s a technique that lets you grow plants hydroponically without any electricity, pumps, or even wicks. You don’t need to change the reservoir or top up nutrients, either. It’s about as close to a “set it and forget it” growing method as I’ve ever come across.

Kratky Systems

A shot of several jars made into hydroponics with developing plants in a well lit area indoors — The technique involves plants growing in nutrient-rich water.

Once you understand the basic principles, this is probably the easiest and most affordable way to grow plants hydroponically. Here’s everything you need to get started with the Kratky method:

In a traditional deep water culture setup, your plant sits in a net pot filled with growing medium and is placed above a reservoir. You then fill the reservoir with a nutrient solution, making sure the water level comes just below the bottom of the net pot.

An airstone is usually added to create bubbles that pop at the water’s surface, moistening the growing media and supplying oxygen to the young roots. As those roots grow longer and hit the nutrient solution, plant growth tends to take off.

With the Kratky method, things work a little differently. You actually fill the reservoir higher, so the nutrient solution reaches up and submerges the bottom third of the net pot. Why? Because without an airstone, your plants need direct access to moisture from the start. This setup keeps the growing media constantly moist and ensures seedlings won’t dry out.

As the plant matures, it naturally draws down the water level in the reservoir. By the time the nutrient solution recedes, your plant will have developed a root system long enough to reach it.

Now you might be thinking, “But wait, don’t airstones do more than just keep the media moist?” You’re absolutely right. And this is where the Kratky method really shines. Since you’re not refilling the reservoir, your plant’s roots are gradually exposed to more air as the water level drops. This gives them access to plenty of oxygen (no airstone needed), allowing the plant to thrive all the way to harvest.

Limitations With The Kratky Method

Like any growing system, the Kratky method has its quirks. If you want a successful grow, there are a few limitations and considerations to keep in mind:

Suitable Plants

A close-up shot of a developing leafy crop on a hydroponic system in a well lit area — Opt for low-maintenance and fast-growing crops.

This method is designed to be simple and hands-off, which means it isn’t ideal for heavy feeders. Fruiting plants like tomatoes, cucumbers, and peppers require more water and nutrients than the Kratky method can reliably provide. Stick to fast-growing, low-maintenance crops like lettuce, spinach, kale, and other leafy greens for the best results.

Pest Problems

A close-up shot of a mosquito on a leaf in a well lit area — Mosquitos can infest the developing plants as the nutrient solution does not circulate.

Because the nutrient solution doesn’t circulate, it can attract pests, especially mosquitoes. To prevent infestations, keep your reservoir covered or sealed in a way that blocks bugs but still allows some air exchange. A simple lid with a hole for the net pot usually works well.

Water Quality

A close-up shot of a nutrient-rich water solution in a jar with a developing plant in a well lit area — Start with high-quality, filtered or reverse osmosis water.

Since you won’t be topping up or replacing the water throughout the grow, starting with high-quality water is essential. I recommend using filtered or reverse osmosis water to keep the PPM (parts per million) as low as possible and avoid salt buildup that could harm your plant.

Monitor pH

An overhead shot of a water pH test strip on top of a jar — Monitor the pH of the mix daily.

Until you get used to preparing your nutrient mix, monitor your pH daily with a pH pen or test strips. A stable pH ensures your plant can absorb the nutrients it needs. Once you get the hang of it, you can set up your system and walk away, letting the Kratky method do its thing.