Gardenboss.org is reader-supported. That means as an Amazon Associate we may earn a small commission from qualifying purchases (at absolutely no extra cost to you).
Recently we published a post about the soil-less gardening method, Kratky Hydroponics, aka Kratkyponics. Now, we’re publishing a second piece about this intriguing form of hydroponics that is steadily gaining popularity with gardeners.
Lovingly referred to as DIY Kratkyponics, by DIY hydroponic gardeners around the world, more and more people are turning their eye to this seemingly too-good-to-be-true electric-less form of advanced gardening.
In this piece, we discuss DIY Kratkyponics in general, as well as break down step-by-step our latest DIY Kratkyponic setup using three sizes of mason jars, modified planters, LECA, and an LED grow light from Spider Farmer.
Read on, below! Or, if you prefer, you can opt-out and read our informative guide to Hydroponic Gardening instead!
What is Kratkyponics?
Kratkyponics is a spin-off of the more well-known advanced gardening technique called hydroponics. In fact, the term Kratkyponics is nothing more than an endearing name given to this one particularly simple hydroponic method.
In this sense, Kratkyponics shares a commonality with other advanced forms of gardening that are also merely hydroponic growing systems by nature but are known by other names. These hydroponic methods include Aeroponics, Aquaponics, Semiponics, Deep Water Culture, and more.
The Kratky method is studied and lectured about extensively by Professor Kratky over the past few decades, hence it is dubbed with the name Kratky Hydroponics, or Kratkyponics for short.
How Exactly Does Kratykponics Work?
Kratkyponics is a simple yet genius technique for growing healthy and organic crops with very little effort. Further, the method requires zero electricity, something no other form of full-on hydroponic gardening can boast.
There are no air pumps, water pumps, airlines, hoses, or filtration systems required by the Kratky hydroponic method.
We find that for this reason, Kratkyponics may be one of the most advanced organic hydroponic techniques ever discovered.
Once you put together your Kratky system, very little attention or action is needed from you until it’s time to harvest.
What You Need To Get Started with Basic Kratkyponics
The basics for building a simple Kratkyponics system include:
- Container with holes(netted pot, yogart cup, or similar)
- Large container with lid/space for grow sites(totes, bucket, mason jar, flower pot)
- Inert growing medium(LECA, sand and pebbles, river rocks, Rockwool, sponges)
- Water source
- Light source
- Nutrients/fertilizer
Again, there are no electrical components such as pumps or compressors needed for this sort of growing system.
How Basic Kratkyponics Works
The basics behind Kratkyponics are simple enough to understand once you give them a few minutes of your time to consider.
Once planted, seeds quickly germinate in the growing medium provided to them. Atop of their water reservoirs, the water slowly leeching up and moistening their root zones, seedlings sprout and baby plants grow upwards towards the light within days.
In the case of a DIY Kratkyponics setup with glass jars, like the one we discuss below, the LECA keeps the thin layer of potting soil evenly moist so long as the bottom of the grow site sits a few centimeters below the water’s surface.
That means you don’t even need to water the seeds, the jar full of water working in tandem with the LECA does it for you. Plus, once the baby plants start growing, their roots shoot down into the water and continue to uptake water without any outside assistance.
The key to successfully growing with Kratkyponic containers like the jars we show you how to build in the next section is to keep things simple and to provide enough light.
Without proper light to warm the topside of the growing medium, be it an inert one, or otherwise, seeds won’t sprout, and/or transplants will simply shrivel up and die.
Provided with the right type/amount of light, the seeds/transplants you plant in your Kratkyponic containers will thrive and grow even more so than those planted outside in the ground.
What’s Bad About Kratkyponics?
One aspect of long-term Kratkyponic gardening that some folks find a bit intimidating is the need for providing your water reservoirs with liquid nutrients.
That said, there’s really nothing to it when you get right down to it.
Most basic general-purpose plant food works for Kratkyponic gardening applications. Just be sure to read the instructions on the product label and avoid over-feeding your plants!
The only other real factor that some gardeners may find as a negative is that you need a decent grow light. Without proper light, your plants are more or less doomed to be mediocre or barely survive.
How to Set Up a DIY Kratkyponics Garden With Glass Jars
We’ve really taken a shine to Kratkyponics over the past year or so, though we’ve been a fan of the basic principles behind it for as long as we can remember.
Below, we lay out a step-by-step tutorial for the latest DIY glass jar Kratkyponic containers we put together for our new indoor garden:
Step 1 – Make a Plan and Gather Everything You Need
Believe it or not, the first step is to make a plan. Seems pretty obvious right? Well, it should be.
That said, when it comes to DIY projects, there is always room for improvision… especially when a plan is involved!
You may not have all of the bits and pieces to build the same exact containers we put together in this tutorial, but we’re betting you do have parts that are just as good(or even better) if you stop and take a look around your house.
After you’ve made it through the entire tutorial here and made a plan, gather up the gear you’ve put together and move on to the second step.
Step 2 – Prepare and Sterilize Your Equipment

The second step to properly building a Kratkyponic grow system is making sure that all of the parts and components of it are clean and sterile.
From the containers themselves to the growing medium, make sure it is all cleaned and sterilized.
We use boiling water for the jars and containers and soapy water for the LECA.
Failing to clean your stuff may result in bacteria, disease, or even live pests showing up in your new indoor garden.
Step 3 – Insert Cups/Grow Sites into the Jars

The third step is simply sticking the containers you’ve chosen to be your grow sites into the containers you’ve picked for water reservoirs.
In the above picture, we’re using black plastic planters that fit perfectly into the oversized mason jars we picked for this particular project.
You can use anything from net cups or planters to empty yogurt or pudding cups for your DIY Kratkyponic grow sites.
Step 4 – Add Water to the Jars

The fourth step is adding water to the DIY Kratkyponics reservoir, and that’s it!
Now you’re ready to get to the funner parts of the project, in the rest of the steps below, like adding growing mediums, planting, and adding lights!
Step 5 – Add LECA to the Cups in the Jars

The fifth step of our DIY Kratkyponics setup involves adding a growing medium to the grow sites if you are going to do so.
Keep in mind that some DIY Kratky setups don’t require any additional growing medium.
In our particular setup, we opted for LECA, as you can see in the picture above.
You could use anything from pea gravel to sand or even peat moss to fill your grow sites, depending on what crop you’re growing.
Step 6 – Add a Thin Layer of Potting Soil, Peat, or Coco

The sixth step on our list is truthfully an optional one, though one we find very much worth sharing with you guys.
Adding a thin layer of potting soil, and we mean a super thin layer, like barely more than the thickness of your seeds, is a huge help.
The soil is easier to warm than the LECA below it, and thanks to having control of your LEDs, you can force the germination of the seeds to occur far quicker than it would outside.
However, if you don’t have the soil, or prefer to simply plop your seeds down into the LECA, you can skip the step!
Note: Do NOT be tempted to use soil from outside plants or gardens as they may transfer bacteria, pests, or disease to your new indoor garden. It would be better to skip the layer of potting soil than to attempt it with outside dirt.
Step 7 – Plant Seeds into the Top Soil

The seventh step is an easy but exciting one; plopping a few seeds into the soil.
Depending on what you’re growing, the proper amount of seeds varies.
In the pictures above, we’re planting lettuce seeds, hoping for multiple plants/harvest.
Kratkyponics is capable of growing just about anything, so you can plant whatever type of seeds you want! Just make sure your grow site is large enough to handle whatever crop you’re aiming for.
Step 8 – Top it Off With a Pinch of Soil and Water

The eighth step is another optional one.
Firstly, you may or may have not even added a layer of soil to the top of your LECA. Secondly, if you’ve set your system up properly, it doesn’t actually need to be watered by you, ever.
That said, adding a dusting of soil over the top of the seeds helps avoid pushing them down and out of the thin layer of soil and into the LECA on accident.
And, watering the thin layer of soil that contains your seeds one good time most definitely helps speed things up by a day or two, in our experience.
But… the choice is yours!
To dust and water… or, not to dust and water?
Step 9 – Place Under Grow Lights

The final step to our DIY Kratkyponics tutorial is sitting your newly created and self-contained Kratkyponic growing systems under some proper lighting.
Hang on a second, before you freak out. You don’t HAVE to use light, but it definitely helps.
If you don’t have lights and aren’t willing to invest in any, that’s ok.
But, you’ll need to count on the sunlight from the windows, or set your containers outside during the day.
In that case, you’ll also need to invest in pest control prevention as well as likely higher evaporation rates.
Either way, the amount of sunlight available dictates what species you may grow successfully which is why we suggest buying an LED grow light, and maybe even a grow tent, if you REALLY want to start an indoor garden.
Step 10 – Follow Up

If you’ve followed the above tutorial, now all you need to do is keep following up on things in general.
Check-in on your plants on a daily basis, multiple times if you can. Check the medium for moisture levels, keep an eye on the amount of water left in the reservoir, and keep things nice and neat.
If you’re using lights, consider placing them on a timer so you don’t have to manually switch them on and off each day.
A Final Word About DIY Kratkyponics
DIY Kratkyponics is by far one of the most basic yet enjoyable/profitable forms of hydroponics that exists. It’s also a great learning tool for children, teens, and adults who’re interested in higher forms of gardening than just basic soil-based growing techniques.
Even more, it is absolutely the most affordable type of hydroponic gardening to get involved with. From start-up to maintaining your garden for the long term, DIY Kratkyponics has the lowest costs attached.
Do you have any experience with Kratkyponics? If so, what do you think about it? We’d love to hear from you in the comments section below!
Thanks for reading and good luck with your DIY setup!
Still not quite sure how this Kratky stuff works? You can read more about the Kratky hydroponic method in our original post on this subject(along with another DIY Kratky hydroponic tutorial.
Amazon and the Amazon logo are trademarks of Amazon.com, Inc, or its affiliates.