A Kratky garden is a simple way to grow a plant. There is no pump and no electricity.
Compare methods
Kratky vs deep water culture is the comparison most people make when they start hydroponics. Both grow plants with their roots in nutrient water instead of soil. Both use a container, a lid, net pots and a hydroponic nutrient. The big difference is how the roots get oxygen.
In a Kratky container, the water starts just at the bottom of the net pot. As the plant drinks, the level drops and leaves an air gap. The lower roots stay in the solution and feed, and the upper roots take in oxygen from the humid air above it. There is no pump and no electricity. It is called passive hydroponics because nothing moves the water. More in Kratky Method for Beginners.
In deep water culture, often shortened to DWC, the roots hang in a reservoir of nutrient solution that is kept full. An air pump pushes air through an air stone in the water, which releases a steady stream of bubbles and keeps the solution oxygenated. The roots can stay fully submerged because the water itself carries the oxygen. The level is topped up and the solution is changed on a schedule.
For lettuce, other greens and many herbs, Kratky is often all you need.
The trade-off is that a DWC system depends on its pump. If the pump stops, roots in a full, still reservoir can run short of oxygen quickly.
Many of the same rules apply to both: use a dark container so light cannot reach the water, keep the solution cool, mix a hydroponic nutrient at the label rate and check the pH. What you learn with Kratky carries straight over to DWC. See Nutrients, pH and Safety for the basics both methods share.
For a first try at hydroponics, start with Kratky. It costs very little, needs no power and teaches you how roots, water, nutrients and light work together. If you later want to grow bigger plants or keep one system running for months, DWC is a natural next step. The six steps in Make a Kratky Garden get you started.
Often, yes. A bucket or tote with a lid and net pots can usually be converted by adding an air pump, tubing and an air stone, and changing how you manage the water level. Start with Kratky, and add the pump only if your plants need it.
An air pump hums and vibrates, and it needs a power outlet nearby. That can matter in a kitchen, bedroom or living room. A Kratky container is silent and can sit anywhere with good light, including spots far from an outlet, such as a balcony railing or a windowsill.
A Kratky container is set up with its water at the start and checked every few days. A DWC system is usually checked more often: the level is topped up, the pump and air stone are kept clean, and the solution is changed on a schedule. Neither takes long, but Kratky asks for less routine.
These are all on the Kratky Supplies list.
Some growers keep Kratky jars on the windowsill for herbs and run one DWC bucket for a larger plant. The two methods share supplies and skills, so running both is simple once you know the basics.
Tip: If a plant keeps drinking its container dry before harvest, choose a bigger container before you choose a pump.
Nutrients, pH and safety guide