A friend of mine, Ingrid, started growing her own lettuce mix at home using a non-circulating hydroponics system.  I was very interested in what she was doing because it requires no electricity and only a one time nutrient feed.  She sent me brief, but great, instructions and I did a little research on the Kratky method of hydroponics and decided to share what I've done.

These instructions are brought to you after six months of successful growing.  Ingrid had been growing for a year by the time I gave it a try.

I've also attached a PDF file of one of Dr. Kratky's papers outlining his method and how it works... if you want to get all "sciency." 
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Step 1: What you'll need

Underbed box 41 QT/39 L (approx 35" X 17" X 6") and/or 5 gallon bucket (I will be using both in these instructions)
Utility knife
Tape measure
Plastic paint primer and paint
1/2 inch x 1/2 inch elbow (optional)
Rubber grommet 3/4 inch OD x 7/16 inch ID (optional)
Clear vinyl tubing 1/2 inch OD x 3/8 inch ID (optional)
1/2 inch drill bit (optional)
2 inch hole saw
8 - 2 inch net cups per lettuce bed.
Strap to hold shape of container once it's filled with water
PH water testing kit
Hydroponic nutrient (your choice of brand)
Lettuce seeds
Place to set up your lettuce beds

This setup should come in at under $30

frojasp9 months ago
Hi Dianne,

I have experienced for 9 months in a container of 22 liter 6 bushes chile is important to note that the temperature of the site or the direct sun dehydrate plants since they are consuming more water and the pH increases causing water stress to be controlled providing more water without nutrients, so other results are good.
diannemw (author) 10 months ago
Well, you could replenish the 1/2 gallon container as needed (leaving air space for the roots), but most important is that the container be able to block sunlight. Good luck!
byakkou10 months ago
Hi Dianne,

i'd like to ask some newbie question regarding this method.
i'd like to test this method of growing in recycled water bottle instead.. is it possible? when u said that 1 lettuce would need at least 1 galon of water. what would happen if i din put enough, like only half gallon?
Hi Dianne,

You did a great job on this project. Thank you for sharing.

Do you have any issues with little pests? Here in CA, I have some big green caterpillars that ate all my mint and cat nip, we also have slugs.

Do you have an update on the peas?
DaveNJ1 year ago
Nice job with this instructable. I have tried Kratky in 1 plastic coffee container and my lettuce has not done so well even after 3 weeks. I started with the nutrients touching the bottom of the net cup but the level has never gone down. I have roots 3 inches into the water. I am trying your instruction of reducing the water level so the roots get oxygen. I also plan to make a container just like you show so I can copy your example exactly. Thanks for sharing this. Look forward to more and good luck on your plants!
frojasp1 year ago
Excellent project congratulations.

I used the method of the wick that is very similar, where nutrients to the substrate by capillary rise the problem is that the fuse very easily rot and substrate must be good at holding moisture.

I will put into practice this technique in order to evaluate it, I would like to comment more on solutions in Colombia not get as easy as shown in the article.
stevewan1 year ago
Hi Diane,
I just joined earlier today and read your interesting article.
It is very nice of you to take the time and effort to put that together.
I live in NW AR, our first frost date is the last of October, I plan on trying your method ASAP.
Thanks again,
diannemw (author) 1 year ago
You're right... that's a very good contribution, thank you!
rrrmanion1 year ago
you could use sand paper to rough up the surface to get the primer to stick even better
rrrmanion1 year ago
you could use sand paper to rough up the surface to get the primer to stick even better
diy_bloke1 year ago
Interesting, but what i dont understand is what happens if the waterlevel sinks below the pots, at a moment that the plants have no roots growing out of the pots yet. It all seems to assume that evaporation and sprouting/growing are all sort of magically connected. Or did I miss something.
diannemw (author)  diy_bloke1 year ago
(removed by author or community request)
Diane, I understand the science. I was just wondering what happens if the water disappears faster than the roots follow, but I guess the plant dies then, unless one fills up the reservoir again
diannemw (author)  diy_bloke1 year ago
So, I guess my response to the point you made in your last communication is that I have never had an experience where water evaporated before the plants rooted and grew. Also, I have never had a plant die prematurely for lack of water outside of human error.
that is good to hear. maybe i worry too much
CityGirl61 year ago
My brother lives in Hawaii too is always very interested int he farmer's markets here. I'll have to send him this to see if he's ready to grow. Thanks for sharing.
WUVIE1 year ago
This is absolutely wonderful! Thank you so much for such an excellent Instructable!
padsurfdon1 year ago
I enjoyed the posting, I also live in Hawaii and am looking into growing our own vegies in the back yard. Vegetables are so expensive here, and trying to live a healthy lifestyle is really "more expensive" food wise. Useful information that may assist me with my initial setups.
Thank you,
rimar20001 year ago
Very, very interesting projects, congratulations.

Holes on plastics can be done with a hot wire or tube, more easily and without break the material.