I made the simplest growing pots!

Just fill the bottom case with water or nutrient solution!

All you need to do is keep in the sunlight. Then, you can easily grow leafy vegetables!

Suitable plants 

Lettuce, baby leaves, basil, shiso leaves, etc.

In the beginning, I recommend using this case to place the seeds on the sponge and let them sprout.

https://www.printables.com/model/571540-hydroponics-smallest-case

After twin leaves appear, you can easily grow vegetables by moving the whole sponge to this solution.

Caution!

Some printing materials may leak water.

I strongly recommend taking waterproof measures such as hardening the bottom with resin.