How to make wooden seed boxes

I want to thank everybody for all the great comments on my previous post – Several people emailed me about how I make the boxes and pots. So here you go! Today I’ll talk about making the boxes, and in my next post, I’ll show you how I make those great little newspaper seed pots.

What is a seed box?  I’m sure some of you are wondering.  I know I was until I discovered this age-old gardner’s tip.  A seed box is nothing more than a mini planter box that can be filled with dirt, and then “seeded”.  The idea behind the box is mobility.  During the day, the box is moved into a nice sunny spot, to allow the seeds to germinate, and in the evening (or rain, or snow), the box is moved to a warmer, safer place to protect the little seedlings.

Now while the climate is mild here in Austin, TX, the soil in my garden is pretty bad.  It’s very clay like, and not the best environment to start new plants from seed.  But I’ve found that once I get a plant going, it is simple to transplant the 3″ tall plant into my garden.  And there is also the cost.  I buy a packet of seeds for 99¢, and can get 20-50 plants from one little bag.  Compare this to $2.99+ for the plants you get from the home centers.  Sure it takes a little longer, but also my survival rate is much higher because the plants are automatically accustomed to my environment.

Now, on to the DIY project.  I used a couple of special tools (router and dovetail jig) in addition to a saw and hammer to make these boxes.  But if you don’t have those, you can simply nail the sides and bottom together to make a perfectly good box.

The boxes began as a simple cedar board from Home depot. I used a 1×6, that is available in 8 foot lengths.  Anything longer and I couldn’t take it home  in my tiny 2-door civic.  Three sides are finished (sanded), and I don’t really do any additional sanding as they live outside and I want them to look weathered over time.

First thing to do is cut the front, back, and sides to length.  There are no exact measurements, I just want each parallel side to be the same so the box ends up being pretty square.  Here are the four boards that I used.

Usually I cut a groove for the bottom to rest in before I cut the pieces, but I was so excited to make more that I forgot that step. I had to go back and make the cut in all 40 pieces after they were all sized, instead of just running a few long boards through the table saw.

Cedar boards are used for the sides and ends of the box

After each piece was cut to size, I brought out my handy little dovetail jig. A dovetail is a special joint that connects two pieces of wood together. Sort of like a lock and key. Precise dovetails are difficult to cut by hand, and while I can do it, this template makes the job much faster. The long pieces get the Pins (the key), and the shorter pieces get the Tail (the lock). I use a Small Router to cut the wood. It makes a bunch of noise, and even more sawdust. I get sawdust everywhere, all over the garage, and of course all over me. Maybe that’s why my wife calls it the sawdust maker, and makes me strip down before I come inside after using it.

I start with 8 foot long cedar boards, and first cross-cut them to the right legnth for the sides and. Then I dovetail the ends. This makes a joint that doesn't need any glue.

The router has a flat bottom with a little silver collar that rides along the fingers of the dovetail jig. The cutter, which extends out from the flat bottom is slightly angled to make the joints. The photo is with the router upside down – fyi.

I use a smaller Porter Cable router with a fixed base when making dovetails.

Here is a close-up of the fingers of the Leigh Super 12 dovetail jig. You can clearly see where the router cuts the wood is at an angle – that’s from the angled dovetail bit.

I cut the Tails first, and then go back and do the pins. Using a 12" Leigh Jig makes the job fast and easy, but generates a TON of sawdust.

Since I forgot to cut the groove for the plywood bottom, I had to go back after dovetailing all the sides, and run them through the table saw. I use my regular saw-blade and make two passes. The plywood bottom is 1/4 inch thick, and my blade is just over 3/16th. So first I push each piece through, and then I move the fence over just a touch to make the second cut. There is no exact measurement for this either, just a little trial and error. As always, be super careful when using a table saw.

Usually I cut the groove for the bottom of the box at the beginning of the process, but this time I forgot, and had to do it at the end, before assembly.

You can clearly see the first cut in this piece, and I’m about to run the same piece through again to make the groove just a bit wider to accept the plywood base.

When cutting a board so close to the edge, I use a sacrifical strip on my table-saw guide so I don't ever risk the blade touching the metal fence.

Instead of buying plants, I start most of my garden from seed.

After the pieces are all cut, it is super easy to assemble the boxes. The sides just slide into place p just like something you would buy from Ikea. I didn’t even use any wood glue to hold them together. The dovetail jig makes such a precise cut, that friction alone holds everything together. Even though I cut enough wood to make 10 boxes, I only needed to make 5. Each box will hold 10 paper seed boxes, (5 of each seed type), and that’s plenty for right now.

Overall, this project took about 60 minutes to do start to finish, and these little seed boxes will last for many seasons.

Do you use seed boxes? Have you ever made a wooden box from scratch? I’d love to hear your comments.