Introduction: Ultimate Vegetable "EarthBox" for CHEAP!! :) TeraHydro Boxes (aka TetraHydro Box) DIY HOMEMADE

Picture of Ultimate Vegetable "EarthBox" for CHEAP!! :) TeraHydro Boxes (aka TetraHydro Box) DIY HOMEMADE


ATTN! If you like this guide please rate it with a 1-5 star rating to the right of this text and leave comments with constructive criticism :) Thanks :)

This is a guide to building a 2 different great "EarthBox" systems for next to nothing in relation to the $50 commercial version. The smaller is a more experimental idea and may just be TOO small... the larger will work as well or better than the commercial counterpart. This instructable will cost you about $10 for EVERYTHING for the smaller and about $15 for the larger... I recommend building 2 of which ever you chose to bring down cost... or build 2 of each like i did :)

EarthBox is a commercial version of a "self contained gardening systems". From here on out i will call mine TeraHydro Boxes... lol... my own brand... lol

TeraHydro Box explains exactly what it is tho... it is basically a hydro system for growing plants that also incorporates a small amount of dirt for plant stability and fertilizer delivery. Further explanation of the science is in the first step of this project.

The advantages of growing plants in a TeraHydro Box are abundant.
-A place to grow for those without "real dirt" aka large yards
-Requires much less space
-Saves huge amounts of water
-Easy to keep plants well watered
-Almost maintenance free all season after planting
-Huge crop yields
-Easy to grow organic or "regular"

Update!!  BOTH the small and large TeraHydro Boxes worked excellent.  The Large TeraHydro Box worked much better than the original Earth Box even!! I harvested gallons and gallons of salsa. Way to much in fact, haha...  While I still recommend 6 tomato plants for the large THB, 2 would be better for the small one.  Six plants was just to much vegetation for such a small area and the plant were a little small from not getting enough light. Check my account soon for more garden projects in 2010!  :)

Step 1: How It Works

Picture of How It Works

Here is an explanation or TetraHydro Boxes and how they work. The first image is a cutaway from the Earthbox website and helps you understand what i am saying if you have never seen one.

Essentially, you have a large plastic tub, with a water reservoir in the bottom, dirt on top with a huge strip of fertilizer, and the whole thing acts similar to a hydro system for growing plants and vegetables. If you don't know what hydro growing is, the short and sweet version is: it it a growing system with no dirt, that allows the roots to grow in a large bucket of fertilized water. After taking apart an Earthbox after a season of growth i discovered all of the roots had reached the water reservoir and were doing just that. NOTE: whether you use my build design or not there are two things i know are very important that most other guides overlook. In order for the "hydro" part of the earth box to work the water reservoir has to be absolutely dark, to promote roots and discourage algae, and there also must be tons of hole in whatever device you use to separate the water and dirt. Other wise you end up with wet dirt, like you needed, but root bound plants which is not as good for plant health.

Earthbox is a good system. A great system even. Just wayyy overpriced. My TetraHydro Box is based off the same principles, and i deviate in a few small ways, but usually will tell why i did and what Earthbox recommends instead. For example... Earth boxes recommends only 2 tomato plants per box, yet i have grown 6, even in their box, with tons of success so that is how i do it now. Perhaps they have a reason, or think they have a reason for why you should only plant 2 plants, but i think its just to sell more boxes... lol... alot of the things they recommend doesn't seem like there is a real solid reason tho... i think they pushed the product to market as fast as possible and did not get real exact on how or why you should plant things a certain way. The majority seems like educated guesses from smart people, so i use their instructions as a guide and experiment with my own ideas too :)

Step 2: Material List

Picture of Material List

I will simultaneously explain how to build 2 different TetraHydro Boxes and I recommend you build 2 of whichever you choose. I need to remind you. The smaller version is experimental!! I have been pushing the limits on the Earthbox since i got it to see how much it can grow, and know that the large TetraHydro Box can grow 6 tomato plants!! But the small TetraHydro box is experimental in that i am now wondering how small the box can be as long as it has essential nutrients and plenty of water.

If you are new to this goring system... just skip the experimental small box, build the large and be amazed!! :)

Everything is nationally available and purchasable at Wallmart and Home Depot. First is the list for each box system and below is a more detail description with important notes on items like the fertilizer and dirt.

Large TetraHydro Box:
-Large 18 gallon storage bin (Wallmart $4)
-Steralyte plastic basket w/ holes (Wallmart 2 for $3)
-2 cubic feet of potting soil (this brand at Lowe's $5, but find it at Home Depot also)
-2 cups of fertilizer (Home Depot $12 for HUGE 15lbs. bag, you can buy way smaller)
-2 cups of garden lime (Home Depot 10 cup bag $3.50)
-About 1 foot of 1 inch pvc each (Home Depot $2.5 for 10 feet)
-6 scrap of any rubber tubing for drain
-Large trash bag

Small TetraHydro Box:
-Small 18 quart dish bin (Wallmart $3)
-Drawer organizer plastic basket w/ holes (Wallmart 2 for $1)
-1/2 cubic foot of potting soil (this brand at Lowe's $2.5 for 1ft, but find it at Home Depot also)
-1 cups of fertilizer (Home Depot $12 for HUGE 15lbs. bag, you can buy way smaller)
-1 cups of garden lime (Home Depot 10 cup bag $3.50)
-About 1 foot of 1 inch pvc each (Home Depot $2.5 for 10 feet)
-6 scrap of any rubber tubing for drain
-Large trash bag

Nothing to specific make sure its large enough and will hold the basket with holes in it upside down. If you don't buy the suggested bin you will have a good understanding of how to pick your own by the end of the guide.
Make sure it fits in your box upside down. you are going to drill holes in the bottom later so it will act as a membrane between dirt and water but allow the roots to penetrate.
Earthbox recommends or more requires that you only use potting MIX... i use SOIL... either is fine... mix just costs more. Earthbox says the difference is that soil contains rocks and mix does not. I have no idea where they came up with that idea. I have never seen a rock in potting soil, and so what if there was a few is it worth double the price? The difference i do know of tho is that potting MIX has already been fertilized and they add perlite. Perhaps that is worth paying double for, i don't know tho. I've used them both in separate boxes simultaneously and noticed no difference.
Earthbox says any fertilizer will work as long as the numbers are 15 or less, as in 5-8-12 or some combination. The one i am using is 16-16-16. I guess I am just defiant... lol :)
-Garden lime
Very hard to find! Strange considering how important it is for gardening tho. Earthbox recommends you use dolomite or hydrated lime. I understand that the lime used for concrete can also be used but may burn plants. The brand I found at home depot was cheap enough and has way more benefits too. The purpose is too raise the soil ph as most vegtables need more acidic soil and also to fortify the soil with calcium. Without your plants may suffer from what is called blossom end rot and it ruins you crop. I have seen it personally years ago and would add the vitamin tablets of calcium or crushed egg shells after ward, but the garden lime i found has tons of other vitamins and minerals too.

Step 3: Begin! Drill Holes

Picture of Begin! Drill Holes

Drill holes all throughout the bottom of your basket I'd say anything between a 1/4" and 3/8" are good... I used a step bit so mine cam out random sizes.

Ignore the etra steps already don on the large one... we'll get there :)

Step 4: Cut PVC, and Bgin Assembly

Picture of Cut PVC, and Bgin Assembly

Cut yur 1" pvc so that it is long enough to reach from the bottom of your box and stick out a few inches. Notch the end if you like to make sure it won't sit flat on the bottom and get clogged.

Next put your basket into your box upside down and cut a corner of the basket to penetrate the pvc through.

Sorry no pic of the large bin because if forgot till i had added some dirt! lol...

Step 5: Drain Hole

Picture of Drain Hole

It is important to put your drain hole at the top of where your water line should be. So put it at the top of the basket. a simple hole in the side will clog with dirt a little and drain slower so i used a small rubber auto hose to "bring" my drain hole inside the basket as pictured. Try to make the hole in the side the same size as yur drain hose but there is no reason to make it a perfect fit or seal it its a drain! :)

forget the dirt in the small one... lol.. the drain hose was a last minute mod :)

Step 6: DIRT! :)

Picture of DIRT! :)

Fill the box halfway with dirt. to keep as little dirt as possible from entering the resevoir it is better to dump the dirt in fast instead of slow.

For the large boxes the take 1 cubic feet of dirt that means add a whole 1 cubic foot bag right now, and for the smaller boxes it only takes 1/4 cubic foot.

Next, fill the reservoir with water till it starts coming out your drain hole. Then thoroughly soak the dirt down for at least 60 seconds so it is completely drenched throughout. You can even "massage" the dirt a little with your hands to get it to soak in everywhere.

Now add 1/2 the garden lime for the large TetraHydro Box, 1 cup, and all of it for the small box,. also 1 cup.

Next, add the rest of the dirt to top off your box and soak the dirt for another 60 seconds.

Step 7: Fertalizer Strip

Picture of Fertalizer Strip

For the small TetraHydro Box there is no garden lime left to add, but for the large box and the rest of the garden lime and for both add your strip of fertilizer. Earthbox recommends different arrangements for different plants, but personally i always grow 6 plants with a strip in the middle. They recommend 2 tomato plants but i have grown 6. Usually i like to mix and match tho. Like 4 tomatoes, a pepper and a large leafy plant like squash or cucumber.

In any case... dig your small trench and add all of the fertilizer. Cover the fertilizer again and when you add the plants try not to disturb the fertilizer strip at all.

The Earthbox recommendations are attached as a pic.

Step 8: Add Cover

Picture of Add Cover

Stretch a large thick trash bag over as a cover. For the large TetraHydro Boxes this is a little difficult. Once the bag is over tho, poke holes thru so the watering pip can come through and to lay out your plants. Make the holes as small as possible.

Step 9: Add Your Vegatbles! :)

Picture of Add Your Vegatbles! :)

Since the small boxes are more experimental i added 4 tomatoes to one and 6 to the other. We'll see what it can handle. With the large boxes tho I know it can handle 6 tomatoes even so one has 4 tomatoes, an egglplant and a cucumber, and the other has 3 tomatoes, a squash, and a cucumber, with one more spot awaiting a pepper probably :)

Enjoy your veggies! :)

ATTN! If you like this guide please rate it with a 1-5 star rating to the right of this text and leave comments with constructive criticism :) Thanks :)


khadern (author)2016-04-19

You can buy the sturdiest tub and materials and spend the same as 4 original earthboxes. Or save time and money

khadern made it! (author)2016-04-15

Don't waste your time and money. Buy the original and it will last longer and work better than this one.

getoffamycloud (author)khadern2016-04-19

There is no reason why this DIY version won't last just as long as the commercial version. If you buy a quality tub then it will probably last longer.

getoffamycloud (author)khadern2016-04-19

There is no reason why this DIY version won't last just as long as the commercial version. If you buy a quality tub then it will probably last longer.

getoffamycloud (author)khadern2016-04-19

There is no reason why this DIY version won't last just as long as the commercial version. If you buy a quality tub then it will probably last longer.

getoffamycloud (author)khadern2016-04-19

There is no reason why this DIY version won't last just as long as the commercial version. If you buy a quality tub then it will probably last longer.

Allaired (author)2016-01-25

Nice DIY, going to build today. Thanks

lee8686 (author)2010-01-31

Fantastic! I love this! May I make a suggestion though. Instead of drilling holes in the bottom container for a reservoir, why not just use clean pea gravel. Do you notice higher yield compared to just plain soil? Or a fertilizer tasting vegetable?

Mary KayB (author)lee86862015-05-24

pea gravel will take up all the space that the water needs to be in! SO no that wouldnt work

brian3140 (author)lee86862010-03-15

I've tested pea gravel, 1" diameter rocks, and like 3-4" diameter rocks.  I wasn't happy with any because the soil eventually washed into the rocks and it was pointless. If you put a screen as many people suggest it blocks the roots from passing. Plus as "incog neato" suggested the large air pocket above the reservoir of water is crucial.  Idk... i guess i just like the colanders, or drilled baskets... whatever is cheap and available :)

brian3140 (author)brian31402010-03-15

Sorry didn't finish responding to the comment...
    Yes the potting mix will usually yield the best results because the conditions are optimum for as broad as spectrum as possible straight from the facility it was produced in. The taste of fertilizer you are concerned about is not there are all thankfully.  Plants do an amazing job at breaking down the elements they need and turning it into something healthy and delicious. Choosing organic fertilizer is also a possibility tho, and personally i'd recommend it,  but make sure your fertilizer strip has 3 cups of fertilizer instead of 2 because it is always a much lower strength. (eg. 5-5-8 instead of regular chemicals ranging between 13-13-13 and 16- 16-16.)
     Even with all said thus far tho..  its entirely possible to plain ol dirt outta yur yard if you prepare it right.  Much more difficult to explain tho. Everyone's dirt is different tho so its hard to explain how to do it without seeing yours.  I'll sorta break it into suggested results for 3 basic types of dirt in case it's helpful.
--Sandy:1 Part your sandy dirt, 1 part compost, 1/2 cup fertilizer per 5 gallons dirt.
--Clay: You have the worst dirt possible. It really would be best to buy potting mix.  You can try making it work tho with a ratio of 1 part your clay dirt, 2 parts compost, 1 part sand, and 1/2 cup fertilizer per 5 gallons dirt. Mix very well.
---Dark and Rich: Add 1 bag of peralite per 5 gallon bucket of dirt. Unless there is cost restriction, that will work best but sand can help also. You are just trying to help it drain better.

JMH407 (author)2011-08-21

I'm concerned about the black trash bag covering. I live in FL and wonder if that would hold too much heat in and cook the plants?

Mary KayB (author)JMH4072015-05-24

Use a white garbage bag in florida in the summer and a black one in the winter (according to the actual earth grow box instructions)

DIY-Guy (author)JMH4072013-02-04

4 words. "White garbage bag coverings."

shuneycutt (author)2015-03-23

Any particular reason you couldn't use the lid of the containers with holes drilled in them for the plants to make it look better?

STEVEN3 (author)2014-09-06

I went to walmart I found tge 18 gal tote for 5.47

I can not find the insert

The one they had was a little different, about $3-4

Also did you think of using the top of the tote and cutting it to fit and use that as the insert



buteman (author)2014-05-14

I think building lime is calcium oxide whereas garden lime is calcium hydroxide.

Adding lime does increase the pH which means the soil becomes less acidic. pH range is 0 to 14 with 0 being very acidic and 14 very alkaline. 7 is neutral - neither acidic or alkaline, If I remember correctly most plants prefer the pH around 6 to 7.5 although there are differences between what each really loves.

Rich_Limburger (author)2014-05-12

ATTN? ow I see another way to write attention nm then clear instructable, i'm gonna try and make one with Ikea stuff

bikeboy (author)2011-03-14

Very inspiring instructable!
As a way to prevent the dirt from dropping through the reservoir holes when filling up the box, you could cover the grate with non bleached household paper. Once the dirt is thoroughly soaked, the paper will quickly disingrate and allow root propagation.

MamaSmurf5000 (author)bikeboy2014-04-27

When I put together my indoor pots, I use coffee filters on the bottom to keep the dirt from washing out the bottom hole. They don't disintergrate like paper and last for years. I think a layer of unbleached filters would work better and last longer than paper towels or any other paper.

RoBear613 (author)bikeboy2013-06-16

plain (non-glossy) newsprint should also work since the inks are soy based.

petercd made it! (author)2014-02-09

I used someone else's idea of the pvc tubes as stilts and cut the lid to retain the outer section as a hold down for a plastic liner, when I find one, then I drilled the lid and laid some paper towel on top to stop the earth from falling through the holes. I followed the Earthbox method of 2 earth riser wicks in the corners and a row of fertiliser under the mound in the middle which also acts as a watershed. I figured a rubber car mat would be better than nothing in the meantime, I have 3 tomatoes in the front getting sun and 3 green peppers at the back, apparently they make good companions. Nice 'ible.

doodadica (author)2013-08-25

Great instructable. Thanks. I'm new to gardening, but I'm wondering what you (or others) would think of using a layer of pumice for the reservoir in the bottom instead of a big open space.

Podsixia (author)2011-05-12

Hey, so I'm a complete gardening noob, and I'm not sure if this will work on my balcony. We're on the 2nd floor, with a 3rd floor balcony above us, so I don't think we get much sunlight there.

For this set up, what would you say would be the minimum required amount of sunlight per day? Thanks,

RoBear613 (author)Podsixia2013-06-16

It doesn't matter how you grow a plant, the amount of sun it needs is the same.

grrrlgeek (author)2013-05-27

I don't know if you check these messages anymore, but increasing pH is decreasing acidity and increasing alkalinity. To increase acidity, you would decrease pH.

Cherisse23 (author)2013-05-12

Made 2 of these boxes today. The drill bit we used was 7/8", so a bit bigger then yours.I hope that doesn't let in to much dirt.

We used one box for herbs (basil, chive, cilantro, rosemary) and the other for veggies (peppers, carrots and cucumbers). Thanks for posting the instructions!

One question. In the begining, when the roots are still making their way down to the water, do we need to water from the top? I'm worried about things drying out.

kimbenoit (author)2012-08-05

I have made some "similar" grow boxes, but I really like the idea of a large dish drainer to support the soil. I was using pvc pipe sections with two sections filled with soil as large wicks.

I think that a cheap fabric mulch cover would help keep the dirt out of the reservoir, but still allow the water to wick to the soil. I get rolls of the stuff from a dollar store for $5. It's only meant for one season anyway. Good for tops, too.

armbml (author)2012-05-16

I cut a 45 degree end on my fill tube instead of a "v" works the same way and I think is easier. Great instructions and comments. i have only been EBing in FL for 2 seasons (1 year) I have found this forum very informitive. Thanks brian.

rjlewis74 (author)2012-04-05

This is very cool. After i found this instructable I started constructing mine last night with a couple variations. Scavanged the garage and reused materials i already had on hand. Only had to go pick up the plants and potting soil.

KendersAngel (author)2012-01-10

Two questions..
1) Does this system work well with starting from seed? ie, could you leave it open and sow seed in there and thin and transfer? Or only with small established plants?

2) if using a pre used bin, how should one clean it to prep it? Pretty sure it has only been used for yard work, But it is pretty dusty and dirty.

BTW you are now my new favorite person. I am going to make 2 a week until I can do my whole yard in these... Well maybe not the whole yard. But definitely the back patio.

malakesher (author)KendersAngel2012-03-09

1) You can grow from seed (or I should say seeds will grow) but beware that if heavy rainfall is likely you will want protection from this as it works against the purpose of the 'TetraHydro Box' and could mess up the fertilizer also getting the bag over the top without damaging the plants may be a challenge, but I would suggest giving it a try and if it doesn’t work then you know :) or even better make two and the first can be with seeds the second with established plant and see what works best.

2) I would try to use only water to wash the bin starting with boiling water to kill anything that might harm your plants, then give it a good scrub with just warm clean water and finally when it looks clean a final rinse with boiling water. There may be some plant safe products out there you can buy but boiling water will do the job just as well.

Have fun and post some picture when you get going let us all see how you are doing.

malakesher (author)malakesher2012-03-09

Also I forgot to mention that strong wind could effect plants that are not strong enough so do take that into account.

Rae Smith Evans (author)2012-01-17

This may be a dumb question, but its the one thing that has kept me from trying this for several years. What do you do with these boxes in the winter? How do you start them again in the spring?

porpor1234 (author)2011-12-31

Great instructable, Brian, for someone not very strong or handy. Did you use anything to support your tomato plants? When I plant in my garden, the wire cages don't hold them up and the location doesn't get enough sun so I get about 1 tomato per plant!! :-(

DougOlinger73 (author)2011-07-05

This is a great innovation and Instructable! I've been playing with container gardens for a year or so. Have not come up with a satisfactory container garden. I have several of the 18 gallon tubs like you show in this instructable.
Going to make several of these right away.
I do have a question tho. What is the purpose of the 1" pvc in the corner. Would you use it to replenish the nutrient rich water?
Also I am reluctant to drill a hole for drainage, unless I plumb the drain line to recycle the spilled nutrients.

msiciliani dixon (author)2011-06-14

ok so I'm ready to try, this looks awesome for my patio...but I don't do commercial fertilizers...I have a worm box and a very THICK layer of castings, but can I just use worm tea for the fertilizer strip? or even a strip of just castings? Do you keep adding to the fertilizer strip or is that just in the intial planting? thank you!!!!!

halindrome (author)2011-06-06

In one of your replies you mentioned that the airspace above the reservoir is critical. This is going to sound stupid, but... if there is airspace between the water and the bottom of the soil area, how does the water wick up into the soil?

dudemanzippo (author)2011-05-21

I live in the south (SoFLA) and it gets hot here. Won't that black plastic promote heat buildup? Is it ok if it does?

michellenergy (author)2011-03-27

Brian - you have created a monster!! lol - i have been making these things for a couple weeks now and i am hooked!! i have made three "large" and three "small" and i have materials to make one more small and three more large ... I am making four "medium" ones in pink for my daughter (5 yrs) and 3 of her friends ... As my veggies get close to needing to transplant from their starter places i move them over and i have been having an absolute blast ... I reviewed several sets of instructions before diving in and yours was the easiest to implement and also follow. Great job and thank you for sharing this with me!! :) ~ Michelle

penandsword (author)2011-02-26

This is a great instructable! I think I'm going to start my own per your instructions this weekend.

A question, though...When you say 'add the plants', how big are the plants you are using? Seeds, little sprouts, or the baby-sized plants like you get in a pot from Home Depot?

CharlesP30 (author)2011-02-19

Excellent tutorial! I built a similar version of these last year and they Worked great. I used 5 gallon buckets instead of Rubbermaid Containers, but the design was the same. Great Instruct-able!

Toulouse (author)2009-05-19

I have been trying to figure out how i would try some semi-hydroponics and found your instructable! thanks man! I'm gonna do this with more emphasis on roots reaching water for some habanero peppers i have growing. I wanna try to get some really potent habanero's. Great instructable, great idea!

brian3140 (author)Toulouse2011-01-02

I hope you did in fact try this as you will yield amazing results in your endeavor lol

brian3140 (author)Toulouse2009-05-20

from my own observations it seems that habanero's roots are not very long... idk if that is always true or just my observation, but i would try very shallow dirt for what you are talking about. maybe 4 inches? idk... lol

ezermester (author)2010-03-27

This planter looks great and I am trying to decide what I want to do.  I have two questions about the Earth box- or any home made version. 

How often do you water them? Does it really need to be filled every day as the earth box instructions say? I though the point of having a "self-watering" system is not having to water all the time.

Is it bad to use soil based mix? Square foot gardening recommends 1/3 compost, 1/3 peat, 1/3 vermiculite, but earth box says no compost and 75-80% peat. Could I use something in between these two recipes? I was hoping to take advantage of the town's free compost, and also rather not use that much peat as it is not renewable. I know I could use coir but not sure if there is a local source and the shipping is expensive for it.


brian3140 (author)ezermester2011-01-02

Yes it should be watered every day or every other day depending on how fast it is emptying. The reservoir should never be dry and always have some water at least.

In regards to your soil question... There needs to be better soil options, yes.
I will be working on a new recipe for the spring of 2011. I am growing organically now and would like the still use my boxes. The organic potting mix and organic dry all purpose fertilizers are an option, but would cost over $20 a box and not an option for me. The reason earth box tells you not to use compost is because it makes to dense of a soil. this system only works with "light" dirt, lots of airspace, and well draining. Compost sops up and holds moisture. So there is my challenge, but I promise I will have a solution for 2011.
I am guessing that 1/3 compost, 1/3 peat, 1/3 vermiculite would work, but would also be expensive. And... peat is not renewable, you are right, however there are alternatives to peat available such as composted tree barks or other regionally available options. Google some :)

Lazooka (author)2010-04-16

Awesome Idea!

brian3140 (author)Lazooka2011-01-02


chefmichel (author)2010-05-03

How much space would you recommend between the basket and the sides of the container ?
What would you consider as a "too small basket"?
Very good and clear 'ible'
Keep updating please.

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