Raised Bed Garden Question

[Mike Goetzke]

We decided to make a large raised garden this year. I have the wood and I've cut most of it to size but have a question about construction. I'm using (3) 2x10's stacked on top of each other for the walls. I could just stack them on top of each other but I found a place that makes custom raised beds and they rabbet the upped/lower board to accept the center one like this (bottom 3 pictures):

http://distinctivegardenbeds.com/rai...rden_beds.html

My longest straight board will be about 3' long - if that matters.


I'm making our garden like this:

http://distinctivegardenbeds.com/Ota_1.html


Thanks,

Mike

[Gene Davis]

IMHO, the rabbet detail is just a design hook, done to make some think there is something more to it than appearance, and perhaps it's doing something good.

Go go ahead and do it if you want the same look.

[Mark Patoka]

I've made 6 or 7 raised beds for my wife, either 3'x5' or 4'x5' in size. I use 1x6 rough-sawn cypress boards, 2 boards stacked on each other for a total height of 11-12" and just screwed to a 1-1/2" corner post. After having them in place for 4 years or so, I can see where a rabbet or spline could be beneficial to provide a little more connection between the boards. Some of my boards started to cup which then opens up a small gap between the two boards. It's usually doesn't cause issues where the dirt will start coming out but there were a few that did cup significantly and a couple also bowed out/in compared to the one it was partnered with.

Instead of using the full 6" width, I cut them into 3" wide boards and then stacked them. That seemed to help with the bowing issue for the most part. That box has been in place for 3 seasons now and appears to be holding up pretty well.

Remember that the boards in a raised bed are always exposed to moisture and the wood, especially in contact with the ground, will be exposed to the natural critters that like to decompose wet wood and it will just start to decay naturally so don't be surprised if you find you have to replace some of the ground boards periodically. We don't use pressure-treated wood because our gardens are organic.

I think the rabbet design on the site you have provides a nice design element with the offset board. Just remember to take that into consideration when/if it comes time to make replacement boards.

[Gene Davis]

Guy showed raised bed work recently on the Festool forum, using the larger dominos to edge-join the sideboards. He used the ones that won't rot, I don't know the material or species, and his tooling was set to have the boards gapped maybe 1/4" when domino-joined. Nice detail.

My domino is the smaller one, the 500, and will only cut for 10mm dominos, but I'll bet the 10mm parts would work just fine for this.

Here they are, to scale, in a three-stack array of 2x10s, gapped 1/4", dominos at 9 inch centers.

[Bill Neely]

I have a lot of raised beds, some are 15-16 years old. If you build them 30" tall I would expect the sides to bulge out sooner rather than later. Something else to consider is that the wood is going to rot at some point unless it's treated which isn't an option with food as far as I'm concerned. All corner solutions, brackets, 4/4s, long lag bolts at butt joints have failed over time and rather than rebuild the beds from scratch I've chosen to drive rebar in to hold the side boards in place.

We have a very wet winter here and you may not experience the same problems.

**My beds are built with redwood.

[Mike Goetzke]

Gene - I was thinking of using some dowels like your sketch shows but was thinking my boards are only around 31" long so movement would be minimized (I think). I know I'm crazy but I want the fasteners hidden so I'm using Kreg HD pocket hole screws to attach the boards - close to 800 screws. I finished the 72 outside boards and it really didn't take long. I built some stops on the bench to locate the boards. Something else I have read and plan to do is line the bottom with hardware cloth with 1/2" square holes. This it to prevent the critters from burrowing into the garden from below.

Also, I called the place that makes the pre-fab raised beds and they said the only reason they stagger the center board is because of the fastening system they use.

Mike

[Kent Adams]

We decided to make a large raised garden this year. I have the wood and I've cut most of it to size but have a question about construction. I'm using (3) 2x10's stacked on top of each other for the walls. I could just stack them on top of each other but I found a place that makes custom raised beds and they rabbet the upped/lower board to accept the center one like this (bottom 3 pictures):

http://distinctivegardenbeds.com/rai...rden_beds.html

My longest straight board will be about 3' long - if that matters.


I'm making our garden like this:

http://distinctivegardenbeds.com/Ota_1.html


Thanks,

Mike

Mike, I know this is now an old thread and you've built your raised beds. I have built hundreds of raised beds. Mine are all framed, thus hiding the nails and the framing gives the boxes a formal look. I also had a ledge on the top with 45 degree mitre joints. The ledge allows me to sit on the box or put items on the box, such as plant flats etc. Mine are typically 4x8 and 24 inches high. Despite conventional wisdom, I use pressure treated wood. The new pressure treated wood is fine to use and the amount of copper leakage has been found to be minimal in studies done at the Ag schools. In fact, the PT wood had lower carcinagins than many species of non PT such as cedar. Just food for thought, pardon the pun.

[Mike Goetzke]

Mike, I know this is now an old thread and you've built your raised beds. I have built hundreds of raised beds. Mine are all framed, thus hiding the nails and the framing gives the boxes a formal look. I also had a ledge on the top with 45 degree mitre joints. The ledge allows me to sit on the box or put items on the box, such as plant flats etc. Mine are typically 4x8 and 24 inches high. Despite conventional wisdom, I use pressure treated wood. The new pressure treated wood is fine to use and the amount of copper leakage has been found to be minimal in studies done at the Ag schools. In fact, the PT wood had lower carcinagins than many species of non PT such as cedar. Just food for thought, pardon the pun.

Hey - perfect timing on your post. I just finished installing the garden this week. I will start another thread. I did use treated lumber. I did tons of research and found what you said.

Mike