As the summer growing season winds down, it’s time to start thinking about the seeds you harvested and turning those seeds into little plants. Growing plants from seeds means you can probably use a seed starter – so get started building your own using these free DIY seed starter plans.

These seed starter plans may appear to be a little more complicated than most DIYers want to tackle, but with a little time and care you can easily handle all of the required cuts.

Materials Required

• 6 – 2×4 @ 8′
• 2 – 2×2 @ 8′
• 1 – 1×2 @ 4′
• 6’x26″ clear corrugated roof panel
• 8′ foam closure strips (for corrugated panels)
• 2 – 4″ exterior butt hinges
• 8 – 1 1/4″ flathead screws
• 2 1/2″ deck screws
• 1″ hexhead screws with sealed washers

Tools Needed

• Table saw or circular saw
• Jigsaw
• Hand saw
• Drill / driver combo

Step 1: Create your 2×4 frames

These seed starter plans begin with cutting down three of your 2x4s into six 48″ pieces, and then cut two more of your 2x4s down into six 24″ pieces.

On the 48″ pieces, you will use a table saw or circular saw to make a vertical kerf cut 1 1/2″ in from each end, 1 3/4″ deep. Now, you’ll need to mark a line 15° up from the end of the cut you just made and use your jigsaw to cut along that line to finish out the notch. Now repeat that process on the other end and the remaining five 48″ pieces.

For each of the 24″ pieces, you’ll follow a similar process except the 15° cut needs to measured on the end of the board (see 4th image below). The easiest way to make certain you have this laid out correctly and that your angles match is to stand your 24″ piece up next to your 48″ piece and scribe the line (see 3rd image below). You can use the jigsaw to make these cuts by setting the blade to a 15° bevel.

When you are done cutting your six 48″ pieces and your six 24″ pieces they should be able to stack together to make your frames. Use exterior wood glue and deck screws going down through the top to secure each corner.

Step 2: Cut your lid wedges

You will need three lid wedges for these seed starter plans. These are made from 2x4s cut down to 24″ and length, then ripped down to 3/4″ on the front and 3 9/32″ on the back end.

Step 3: Add lid front and back frame

Next cut the lid front and back frame pieces. The back pieces are cut from 2×4 stock to 21 3/4″ in length, while the front pieces are cut from 1x2s also cut to 21 3/4″ in length. All four of these pieces will need to have 6° bevel cut on the top edge so that the back edge is slightly taller than the front edge. This should make their slopes match those of the lid wedges you cut in the previous step. I prefer to use the table saw to cut these bevels, but if you don’t have a table saw, you can use a hand plane to create the bevels after you assemble the frame.

Use exterior wood glue and 2 1/2″ deck screws to join the outer back corners. You can just use exterior wood glue on the other joints. Clamp everything in place while the glue dries.

Step 4: Add lid 2×2 frame

The lid has a second layer of boards, all of which are cut from 2×2 stock. There are three boards cut to 24″ in length that will be glue on top of the lid wedges cut in Step 2. There are two 48″ boards that make up the front and back of the lid. Both of these 48″ boards need a 6° bevel cut on one edge. This bevel should be put towards the front and back when assembling the lid.

Use exterior wood glue and a single 2 1/2″ deck screw at each connection of the 2×2 frame. Then secure the entire 2×2 frame on top of the wedge frame created in Step 3 using wood glue.

Step 5: Add corrugated panel roof

Now it is time to add your clear roof panels. Cut your 6′ corrugated panel into two pieces measure 26″ x 27″. Then lay these pieces on top of the lid frame you assembled in Step 4. These two panels should overlap in the middle, and overhang the edges of the frame. Position your foam closure strips under the corrugate panels, on top of the wood frame, then use the hexhead screws and sealed washers to secure the panels in place. It’s a good idea to pre-drill the holes to prevent cracking the corrugated panels or splitting the wood frame.

Step 6: Install lid hinges, and finish

Time for the finishing touches of these DIY seed starter plans! Use the 1 1/4″ flat head screws to attach the two 4″ butt hinges to the lid and the frame. Then add a coat of stain and sealant and this seed starter is ready to use. Put it in place, then drive 2×2 stakes into the ground on the inside of each corner to keep it from shifting and you are ready to fill it with dirt and start growing.

If you have any questions or comments about these DIY seed starter plans, leave us a note in the comments section below.

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