How to Build A Mini Greenhouse Hot Cap

About a month ago, I started hankering for a hot cap to grow more lettuce in. Now, I’m not a carpenter, in fact, when I try to nail wood together, I usually end up with bent nails and split boards, but I was determined not to burden my dear husband with the matter, and do it myself.

So I started working on plans including two-by-sixes, and lots of mitered corners.

And then Gabe said, “don’t worry, I’ll do it”.

And roughly an hour later, we had it sitting beside the driveway.

How does he do that? I don’t know.

Okay well, yeah, I do in theory, but for me to just go out and nail it together without a plan or instructions? Not gonna happen.

This whole shebang cost roughly $20 to build, and should hold enough lettuce to feed us and some neighbors all spring. They’re not just for lettuce though. If we had enough of them, I’d use it to start things like broccoli, cauliflower, cabbage, and peas in late winter.

So if you’re a little carpentry challenged like me, but want a little something to warm your garden spot up, maybe this’ll help. I’ll sure be referring to it for my next hot cap (because one is never enough you know ).

How To Make A Mini Greenhouse

First, gather your supplies:

• 3 2x6x8s (we ended up with 2x8x8s Oops!)
• 4 1x1x8s
• wood screws
• plastic (greenhouse plastic preferred)
• Saw
• Screwdriver or drill with appropriate bit (flat, Philips, hexagon, etc.)
• Staples

Step 1.

Cut one of the 2x6s in half for your short ends.

Step 2.

Screw the short and long ends together.

Step 3.

Take the four 1x1x6s and cut them down to 4’ 2” to make stringers for bracing the plastic covering.

Step 4.

Use the short ends of the 1x1s you just cut to make corner braces. Miter them to appropriate angles. An easy way to do this is to place the boards over the boards you want to screw them on to, and use a pencil to mark where they need cutting. This eliminates the need for a miter box or miter saw.

Screw them in.

The corner braces aren’t strictly necessary, but it sure helps with the sturdiness when you’re lifting the hot cap up and down to plant or water your seeds.

Step 5. 

Again using the short leftover 1x1s. cut two 1’ pieces for the high side of your hot cap. Attach them with screws onto the outside corners of what will be the “back” of your hotcap.

Step 6.

Attach the 1x1x8 to the top of these 1’ pieces.

Step 7.

Take the 4’2” 1x1s and space them evenly along the 8 foot length of your hot cap frame.

Step 8.

Nail them onto the inside of the “high side 1×1, and the inside of your “low side 2×6.

Step 9

Cover the frame with plastic.

You can use a single piece, as Gabriel did, folding it at the corners like you’re wrapping a Christmas present, or you can use pieces, Stapling them to the frame. Your preference. Just make sure the whole thing is covered to keep cold drafts out.

Your done!

You can, and probably should, use small battening strip to nail the plastic to the top of the stringers. The strips will keep the staples from tearing through the staples.

We haven’t gotten around to doing that to ours yet, but certainly plan to.

This thing is a beast – especially since we accidentally ordered 2x8s instead of 2x6s, but that makes it sturdy.

So, what do you think? Are you planning a garden this year too?