DIY Kratky Hydroponics Guide (Beginner Friendly)

If you are interested in growing your own plants and vegetables, finding the quickest and easiest way to do so is probably the top characteristic. Growing a hydroponic garden is way easier than it sounds. You don’t need to have expensive equipment or a lot of space to start a hydroponic garden.

Hydroponic gardening is a way of growing plants without needing any soil. It is a great way to nurture plants inside all year without having to depend on the weather. These types of systems also don’t take up much space, so they are great for small places.

One of the most popular ways to start a hydroponic garden is with the Kratky hydroponics method. What is this method, and how does it work? Keep reading to learn more and get some helpful information on starting your own Kratky Hydroponic Garden.

What is Kratky Hydroponics?

Kratky Hydroponics was first discovered by University of Hawaii graduate B.A. Kratky. This method is very similar to that of the Deep Water Culture. The Deep Water Culture is easy, but the Kratky method makes it even easier and less expensive.

With the Deep Water Culture, you need an electronic pump to circulate the water. The Kratky method doesn’t require any electricity to run properly. It is extremely common to hear this method called a “set and forget” solution for hydroponic gardening. 

With this method, the plants are left alone to grow until it is time to harvest them. This system is very passive and easy for even the newest hydroponic gardeners. The plants don’t need any nutrient changes like other systems might, making the Kratky method low maintenance.

Plants require water, oxygen, and proper lighting to grow and thrive. To help them reach their full potential, plants also need the right mixture of micronutrients and macronutrients. With the Kratky Hydroponic method, the required nutrition is added directly into the water reservoir.

The plants are then placed in a net pot and hung over the water. The roots of the plant will need to be slightly submerged into the water while still being exposed to the air. This will ensure that the plants are getting both the oxygen and the water they need.

As the plants start to grow, the water level will start decreasing. When the plants soak up the water, the roots are exposed to a larger gap of air that allows the plant to respire. For plants and vegetables that grow quickly, when the water in the system is almost gone, it will likely be time to harvest.

If the plants need more time to grow before harvest time, add more water and nutrients to the system. You will also need to recheck the pH level to make sure it is perfect for the plants.


There are several pros of using the Kratky Hydroponic method. The largest one being that the method is so passive you don’t really need to do much to keep up with it. Once you have the initial set up complete, the plants will take care of everything else on their own. Even if you are notorious for killing plants, this system is for you.

The set up is also incredibly simple and you don’t need any special skills to take care of the plants. Some other hydroponic systems require a lot more work when it comes to set up. You don’t need any pumps to keep this system going.

That brings us to another pro of this system. There is no need for any electronic motors or pumps to circulate the water and filter it. These tools can be noisy, so it will greatly benefit you to avoid them completely. This also means your electric bill won’t suffer.


The Kratky Hydroponic system is a fantastic system that doesn’t take much maintenance, there are some cons to consider. The pros definitely outweigh the cons, but it is still important to keep them in mind. The largest con is this method doesn’t work for all plants.

The Kratky Hydroponic method is best for plants that grow quickly and have a short cycle. This limits to leafy greens and some herbs. Root vegetables are not a good option for this method because they require significant maintenance and effort.

There is also an increased potential risk of pests. The standing water can attract several different types of insects, including mosquitoes. This won’t be as large of an issue if the system is staying inside, but it will be a big problem for outdoor setups. 

Another problem with an outside setup is that the nutrients in the water can grow algae when exposed to sunlight. This can easily be prevented with a solid-colored container instead of a clear one. This will prevent light from hitting the water and the growth of mold from occurring.

What Do You Need to Setup a Kratky Hydroponic System?

There aren’t many supplies needed to set up a Kratky Hydroponic system, which makes them even more desirable. They are simple, inexpensive, and effective. Here is a list of everything you will need to successfully setup a Kratky Hydroponic system.

The size of the container you choose will depend on how large the plants are that you are planning to grow. If the plant is small, you might be able to set up the Kratky Hydroponic system in a milk jug. Otherwise, the perfect container is a five-gallon bucket.

The lid can be plastic or Styrofoam, either will work just fine. The lid is an extremely important part of the system. It will work to protect the plants from diseases and pests, while keeping the water in the container from evaporating.

The size of the net pot will also depend on the size of the plant you are growing. A three-inch net cup will likely do the job for most plants, but you can adjust the size as necessary. Since it is recommended to only grow small plants, it isn’t necessary to go larger than three inches.

The growing medium is an important part of the plant’s growth. Since this method is a way of growing plants without soil, you will need a different kind of growing medium. The proper medium will have a neutral pH level and adequate aeration. Some of the most popular are clay pebbles, rockwool, or perlite.

The hydroponic nutrient is another extremely important part of growing. This is a liquid nutrient filled with all of the nutrition a plant needs to grow healthy and strong. This solution makes it easy to measure and give the plants the exact amount they need.

A pH measurement tool and control kit will allow you to always keep an eye on the pH level of the water. If the level is too high or too low, you will easily be able to adjust it with the control kit.

How Do You Set Up Your Own Kratky Hydroponic System?

Setting up a Kratky Hydroponic system is so easy and perfect for beginners and experts alike. There are only six incredibly easy steps to set up a Kratky Hydroponic system.

  1. Gather all of the materials listed above. It is important to make sure you have everything before you start, so you don’t have to delay to go grab more materials. 
  2. After you have all the supplies, you will start by drilling a hole in the lid you obtained. The hole will have to be large enough to fit the net pot you have.
  3. Fill the container with water and add in the hydroponic nutrient solution. The water can be distilled or tap, as long as it isn’t contaminated. The solution you add will depend on the plants you are growing, so be sure to research the plant to get the right nutrients. Add the amount of nutrient solution they is suggested on the bottle as each liquid is different. Stir to mix.
  4. Adjust the pH level to the one that your plant requires. This will also take some research to determine as each plant is different. It is most common for the pH balance to be between 5.5 and 6.5. Check the pH level and use the control kit to reach the proper pH.
  5. You will then fill your net pot with the growing medium. When the pot is ready, you can put the seeds in. It is recommended to put a few seeds in the pot to increase your chances of successful germination. If more than one of the seeds sprouts, you will need to downsize to just the most dominant.
  6. Place your net pot into the hole you drilled in the lid. Make sure the roots can touch the water while still having enough oxygen.

After you set the system up, the Kratky will maintain itself. You will just need to monitor to make sure there aren’t any changes in the health of your plants. 

What are the Best Plants to Grow with the Kratky Method?

Before you start growing plants with the Kratky method, it will be beneficial for you to know what plants thrive with the method. Just like other plants, growing conditions will impact the outcome of how well the plants grow. In general, these are some of the best plants to grow.


Leafy greens are extremely nutrient-dense, and they are perfect for growing and thriving with the Kratky method. Some of the best greens to grow are:

  • Chard
  • Spinach
  • Bok Choi
  • Kale
  • Radicchio
  • Escarole
  • Mustard greens
  • Mesclun
  • Rapini
  • Arugula
  • Tatsoi
  • Collard greens
  • Watercress
  • Endive
  • Fennel


Lettuce is another great option to grow in a Kratky system. There are tons of different types of lettuce to choose from, and every one of them will thrive in hydroponic growing conditions.

  • Tom Thumb
  • Romaine
  • Looseleaf
  • Boston
  • Crisphead
  • Little Caesar
  • Coral
  • Butterhead
  • Oakleaf
  • Ruby
  • Dynamite
  • Grand Rapids
  • Parris Island
  • Paris White
  • Iceberg


Herbs grow quickly and are ready to harvest before you know it. The ones with the ability to tolerate having damp roots will thrive best in this system. These herbs include:

  • Thai basil
  • Italian basil
  • Mint
  • Lemon basil
  • Garlic chives
  • Sage
  • Dill

These types of plants thrive in a Kratky Hydroponics system for three main reasons. Plants that have a fast rate of growth, small size, and leafy crop are best for this kind of method. This makes the difference because of how the Kratky method operates.

At the start of the growing process, the roots of the seedlings will just touch the surface of the water. After a few weeks, the roots grow and absorb the water from the tank. The Kratky method is a passive one, and because of this the growth of the root should equal the decreasing water level.

Plants with the ability to mature quickly and have constantly damp roots are going to perform the best. Most of the plants listed above mature and become ready for harvest in six weeks or sooner. This lets them get through their growth process before all of the water and nutrients get soaked up.

It is recommended to keep the plants small because they are more manageable. If a plant is too large, the system won’t be as efficient and takes more to keep up than is worth it. Larger plants have more risk of stunted growth, frequent refills of water and nutrients, and the tank can become top heavy.


The Kratky Hydroponics method is a great way to grow a variety of plants in a simple, inexpensive system. This system only needs a few materials and can be set up in less than six steps. The best part is you don’t have to do much to keep up with it.

There are only a select few plants that will work in a Kratky Hydroponic system. You will have the best success with plants that grow quickly and are leafy. Most leafy greens will thrive, along with some herbs and lettuce. 

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