Building a Grow Box

A few weeks ago I went to the East Austin Garden Faire, and one of the booths was about building Grow Boxes for gardening instead of your standard garden.  In college, I had a commercial grow box (the EarthBox - Retails for $42.95 -shipping included- -does not include soil or fertilizer - and is 2.5' x 1' x 1' [which holds 2 cf of growing media 8" deep and approximately 3 gallons of water]).  I grew broccoli in it.  Lots and lots of broccoli.

This year, because of the 2011 drought, I opted not to do a spring garden.  Which then put me in a quandary when I picked up a free tomato plant at the faire.

Unknown variety of tomato plant from East Austin Garden Faire

Thus I decided I needed a grow box.  Good thing they nice people at the grow box booth had given me a set of directions on how to make my own.

Materials Needed for the Grow Box:

• 30 or so gallon plastic storage container (e.g. Rubbermaid or Sterilite)
• Sturdy "water reservoir" supports (i.e. high quality gallon sized plastic pots or 4" PVC cut into 6" long pieces)
• 2' of 1.5-2" PVC pipe (this is your watering pipe)
• length of wire to provide lateral support to your grow box (I used electric dog fence wire)
• Duct Tape
• Garden Soil and Compost (about 2-3 cubic yards total)
• A good general granulated fertilizer (NOT the type that you dissolve in water)

Materials needed to Make the Grow Box:

• Something to cut plastic (such as a box cutter or a cutter saw)
• An electric drill fitted with 1/4" drill bit
• Hand saw (depending on if you need to cut PVC pipes)
• Pliers (for twisting wire)

Cost:  $22.70 (in order to compare apples to apples, this cost does not include soil or fertilizer)

Step 1:  Set out your materials, thusly:

Step 2:  Situate the gallon plant containers and/or 6" PVC with the 2' PVC roughly in the middle of one of the sides as such:

Notice that 2 of the containers in the corners are open end up. This is because you need a way for soil to wick water from the water reservoir.  Technically I guess all of the containers could face up, but only the 2 opposite corners are going to do the wicking.

Step 3:  Cut out the center part of the lid.  I used a box cutter (relatively easy - but you do have to make 3 slices in order to cut all the way through the lid), but you could use a power saw of some type.

Step 4:  Cut out the corners and a circular hole for the watering pipe.

 

Step 5:  Drill some drainage holes in the lid (using the 1/4" drill bit), and duct tape the lid (which is now the floor) in place.  The duct tape is to prevent soil from falling into the water reservoir.  At this point, just use enough to hold the piece in place.

Step 6:  Drill some 1/4" holes in the watering pipe.  I also cut it at an angle but you don't need to do this (the husband insisted that this project required the use of the destructo-saw aka reciprocating saw)

 

Step 7:  If a little duct tape is good, then a bunch of duct tape is even better.

Make sure to put the snapping part of the lid on the container in order to make sure that your watering tube is situated correctly before you go duct taping it at the wrong angle.

Step 8:  Drill a few holes (4) in the long side with matching holes on the opposite side - you will be threading the wire through these holes for lateral support of the box.  Drill a few holes (3) just below the flooring - this is how the water drains out and is really what makes this fool-proof.  Only drill the 3 holes on one side, and preferably it should be on whichever side you'll be looking at while you fill the thing with water.

The 4 wire support holes are lighter in color and are above the dark line (which is the floor), the 3 drain holes are darker in color and are below the dark line.

Step 9:  Thread the wire through to provide lateral support.  We also threaded it around the water pipe for added support.  Make sure to twist the ends and tuck them away so you won't be stabbing yourself while filling the box with soil.

Step 10:  Fill the corners of the box (the wicking pots) with soil.  Tamp down the soil.  Add more soil and some compost until about half full.  Lightly tamp down and moisten the soil (you don't need it sopping, just somewhat wet to get things to settle).  Continue filling with more soil and compost.  Tamp down lightly and moisten again. (no more pictures because my hands were dirty)

Step 11:  Make a furrow in the center of your soil box - it really depends on how you plan to plant your transplants.  The furrow is where your fertilizer will go so you don't want to have a plant smack dab in the middle of it.  Pour some fertilizer in the furrow - probably between 1-2 cups - in a strip approximately 3" wide.  Cover with soil.

Step 12:  Use a trash bag to create an anti-evaporation cover (this is why seeds don't work well in the grow boxes).  Basically all you have to do is lay the trash bag over your soil and snap what's left of the lid onto the base.

Step 13:  Cut holes in the trash bag where you want to plant your transplants.  Plant.  Voila!  The grow box is complete. 

 

Continued Care:  Now all you need to do is water the plants via the watering pipe until water runs out of the 3 drain holes.  It takes a while for it to fill up the first time - the water reservoir, after all, does hold about 8 gallons of water.  Frequency of watering will depend on how much water your plants use - young tomato plants use less water than mature plants; when it's hot, plants will use more water than when it's cool...and God bless us if it's hot and windy.  Basically, you'll have to still check to make sure there's water in the reservoir, but you may be able to go up to a week or so without needing to add any water to your grow box system.

Long Term Care:  If I remember correctly from the EarthBox system, you should refresh the fertilizer every year, and the soil may need to be switched out every 5 years or so...of course, by that point in time you'll probably need to re-duct tape everything anyhow.