How to build a grow box for less than $100

When my husband and I moved into our first home, we were so excited to finally have a backyard. For us, a backyard meant BBQ's, kids with grass-stained pants, hammock lounging (still waiting for our hammock), and finally, a vegetable garden.  

Here is step-by-step tutorial on how to build a basic grow box. There are books out there that explain this in much greater detail, but if you're looking for something basic, this tutorial will walk you through it. We built both of our grow boxes + soil + seeds for right around $160. Not bad at all! If you want to start with one grow box, you'd be looking at under $100. Can't beat that!

Our two grow boxes are 6' long x 4' wide and have a depth of 8". The following measurements/materials are based on this. (Note: if you're making only one grow box, you will cut these measurements in half)

What you'll need:

Go to Home Depot, Lowe's or a lumbar yard and grab yourself the following things:

  • Four 2x8x10" beams. Make sure they are straight by examining them from the side and looking for any obvious bowing. Have a worker there cut them all at 6', so you're left with a 4' side for each one. This will be all the wood you'll need for two grow boxes. At $9.77 each, this came to a total of $39.08.
  • A pack of 3" deck screws or "grabbers": $14.96. If you already happen to have 3" screws, you'll only need a total of 24, so that can save you some money.
  • 6'x50' weedblock fabric. This was the smallest size available when I went, so you can totally spit this with someone else! The cost of this was $24.97.
  • If you are planning on doing tomatoes, peas, beans, or anything that you want to climb up a trellis, then I would recommend getting either PVC pipe, or 1/2" conduit, 90-degree angles to hook them together, netting, and some rebar to anchor them into the ground. You'll see in my pictures that I haven't put in my netting yet, but you'll get the idea of the trellis.

That comes to a total of only $79.01!! You'll be surprised at how easy they come together.

  • Now for the soil. My mom gave me a book I'd highly recommend called Square Food Gardening, by Mel Bartholomew. This guy knows his stuff. For the soil, he recommends getting a combination of several different things:  peat moss, vermiculite, and some different composts to mix. My mom bought them all separately and combined them (he teaches how to do this in his book), but I went for a little easier, faster, and less expensive route since we wanted to get ours in quickly.

I bought 1 cubic yard off of Big Yellow Bag. I highly recommend this company! It's easier than ordering pizza! I went with the BYB Biogarden GROmix Soil at $144. I then split it with someone. This soil has a mixture of peat moss, vermiculite, topsoil, and some different manure in it. They delivered the big yellow bag of soil right to my house, and it came within 2 days! I split the cost with my aunt, who used the other half, and viola! The one problem with this was transporting the other half to her house. One bag weighs ~600 pounds, and so even half of it was still ~300 pounds. We had to get several people to lift it into the truck to transport. So, if you share with someone else, be warned that the bags are heavy!

In hindsight, I would've done the soil a little differently. I later spoke with a woman on the phone from Big Yellow Bag and she said that if you just wanted the half cubic yard and you owned a truck, you could actually put tarp down in the bed of a truck, and go pick it up yourself, saving you the shipping and delivery cost, and it would come out $35 not including taxes!! So really, you could do both grow boxes for around $120 if you're pinching your pennies! I think that's a smart idea if you own a truck. Their address is 9980 South State Street, in Sandy. Their telephone number is 801-562-9090, so be sure to call beforehand to make sure the pricing is still the same and that they still offer that option.

  • You will need a Phillips screwdriver, and a hammer


  1. Clear your grow box area of weeds, till the soil, and level off your plot where the grow boxes will go. I used Roundup Extended Control to spray over everything once it was all leveled off, because we used to have weeds galore in that space.

2. Lay down the weed blocker fabric and cut to size. We had little stakes to keep the corners down, but you could just put heavier rocks on the corners to set in place.

3. Lay out your wood and arrange in box shape. You'll want the corners to look like this (below). If one side of your board is the inner side of the angle, the other side of the board should take the outer angle. This way, your measurements are even around all sides.

4. Take your deck screws and put three screws in each angle, one on each side and one securing the middle down.

5. Once you've made your box, lift it carefully over to your weed blocker fabric and set in place. Repeat steps 3-5 again for a second box.

6. Take your soil and gently fill boxes, evening out the top to desired height.

7. Follow the instructions on individual packages for seeds. We planted tomatoes, beans, strawberries, zucchini, yellow squash, kale, and romaine lettuce. Can't wait for harvest!!