Picture of keyhole garden using reclaimed materials
I wanted to build a raised garden bed this year and decided that I had enough materials around the homestead to build one. My goal was to build it with little or no cost using reclaimed materials. I found a spot near my greenhouse that I was also building at the time that looked to be pretty level.

Step 1: First things first

Picture of first things first
I wasn't sure how big I wanted to make this, but knowing that I only had a few cement blocks to work with, I decided to go somewhere around 7 or 8 feet. I put a stick in the ground and tied a piece of bailing twine to it and cut off a length that looked about 8 feet. I then placed a block at the end of the string about every three feet until I had a perfect circle. I rearranged the blocks to get them to line up and then eye-balled the keyhole part to where it not only looked right, but big enough to be able to work in there.
breumer2 years ago
Very nice rollincaswell ! Through your project I have now a project ;) ! Thanks !
rollincaswell (author)  breumer2 years ago
Thank You breumer... I wish you all the best in your future projects!
mkinoma10 months ago

As noted below, this is not actually a keyhole garden. But it's a very nice and convenient looking planter.

rollincaswell (author)  mkinoma10 months ago

@ mkinoma, YES IT IS!

It's missing the key element of the compost tower in the center. Pouring in the water through the compost tower allows the nutrients to move outward into the garden, which is what gives keyhole gardens their capacity for amazing productivity.

Don't get me wrong; I like both your planter and this instructable.

rollincaswell (author)  mkinoma10 months ago

@mkinoma, Thanks very much for the compliment, I appreciate that very much. I chose not to include the tower into my build mainly because I already have a compost bin. I add that into the soil in the spring and throughout the growing season by hand. I have so far been very happy with the productivity of this build with both roma tomatoes and sweet corn over the last two growing seasons. I have always left the option of a composting tower on the table, but at the present time, I don't have a need for two composting sites.Nontheless, it is a keyhole garden even tho it doesn't have a composting tower.


rollincaswell (author) 1 year ago

I have added a couple of pics and an update to this project. This truly is a very convenient and functional garden. It as an absolute pleasure for me to go out there everyday and not really have to do anything other than a little bit of weed pulling and giving it some water or fertilizer when needed.

jmwells1 year ago
How about an up date. Did all grow well? What ya got this year?
rollincaswell (author)  jmwells1 year ago

Hello jmwells! I will be posting my updates shortly :) Thanks for reminding me to do so! Have a great day buddy.

No problem. Just curious. It's a good ible. Needs more attention.
jbignell12 years ago
What makes a keyhole garden more then just a raised bed is the centre and the ability to water and provide compost in the centre. This design will not work as a keyhole garden should. It's just a shaped raised garden bed.
rollincaswell (author)  jbignell12 years ago
your point is taken.. however this, my design is more for the purpose of "access" to all of my plants without adding compaction, or possible breakage of my plants from stepping on them. I can access them from both the inside "the keyhole" and the outside. I added composted manure on top of old barnyard dirt, which should have plenty of nutrients to get me through the growing season. As far as water, that is why I added the cedar mulch on the surface to help to maintain moisture in the bed. No, my design will not work like a traditional keyhole garden will, but it will work for the purpose for which I intended it to. cheers!
Great job! I love this idea, and the easy access is wonderful! Thanks for sharing! :-)
rollincaswell (author)  WUVIE2 years ago
Thanks WUVIE!
antioch2 years ago
Well done with the reclaimed materials but I always thought a keyhole garden has a composter in its middle. It's what makes them so special.
rollincaswell (author)  antioch2 years ago
thank you Antioch, please see a comment from

and my response.
I had a feeling I should have read all the other comments first =)
nice, I should do this
Thanks pianolover... if you decide to do this, I wish you the very best!
This is perfect! Love the design. :D
rollincaswell (author)  jessyratfink2 years ago
Thanks jessyratfink!..
i have always wanted a key hole garden but i could not find the right instrutions on how to make one but now i do know how and thanks rollincaswell
rollincaswell (author)  supreme creator2 years ago
your welcome supreme creator.... best wishes on your future projects!
This is a fantastic project. Please add pictures as things start growing.
rollincaswell (author)  joppenheimer2 years ago
thanks joppenheimer.... I plan on a updating pictures all through out the growing season! Cheers!
itsmatt2 years ago
Neat idea, Rollin. Definitely solves the "how do I get to the center of the planting bed" problem. Plus, anytime one can use reclaimed materials (and baling twine!), I think it is cool.

The only comment I had about a possible improvement was to lay some weed fabric down under the cinder blocks to keep the weeds from pushing up between (and up through) them. If you had a few bricks that you could put between the cinder blocks on the outside to fill in the spaces, it would hold down the weed fabric at those points as well.

Well done!
rollincaswell (author)  itsmatt2 years ago
great idea matt... I never thought too much about the issue of weed/grass growth up through the cinder blocks when I first started putting this thing together. I'll definitely address this in the upcoming week.
artworker2 years ago
cool! Cover it with a geodesic greenhouse!
rollincaswell (author)  artworker2 years ago
I may just have to do just that! I heard on the weather report this morning that they are calling for frost possibly next week. I'm thinking some 1/2" pvc pipe, and some leftover 6mil plastic that I have extra of from my greenhouse.
Fun! I just love that design, very different :)
rollincaswell (author)  Penolopy Bulnick2 years ago
thank you!