A nicer looking garden bed made from Corten (weathering steel) that should last much longer then our wooden beds, and develop a nice patina.
We have been thinking about adding more raised beds to our gardening setup (grew to 12 by Spring 2020) and wanted to try out a metal bed. The advantages are that it lasts much longer then the untreated wood we’ve been using which rots out after 3-5 years, as well as looking attractive. The downside is that it costs much more then untreated wood, though in the long run it should be a good investment.
We purchased a 4’x10’ sheet which the supplier cut down to two 2’x10’ sheets at no extra cost. Then I cut each of those sheets into a long and short side for the bed with an angle grinder, being very careful to keep a straight line so the corner looks crisp.
I then matched up all the sides and welded up the box. My welder is about as low end as you can get and creates a lot of splatter. I chose to only weld the inside of the joint, so I wouldn’t need to go a lot of cleanup grinding on the visible surfaces. The bed felt sturdy enough without welding the outside of the joints.
To give the bed some more strength along the long walls to keep them from bowing out, I welded in 2 pieces of rebar. These also acted as helpful handles for moving the 100+ pounds of steel into position when installing the bed.
I found that leveling this bed was much easier then the wooden beds I’ve built in the past. We would set the first corner where we wanted it, drive in a rebar stake and weld it to the bed. Then we could continue around the bed, making it level and welding it to a stake in the ground.
Since we were putting the bed directly abutting the sidewalk, I made a wooden surround to cover the sharp metal corners and make it more attractive.
The patina develops naturally over time, but for the first couple of days I sprayed the bed with a vinegar salt solution to speed things up.
This will be our new greens bed, we’ve turned out old greens bed over to more tomatoes. As of August 2020 it is doing ok, but not as good as the former greens bed - we suspect the soil is lacking in nutrients of some sort, or the drainage situation has changed with a change of soil and bed height and it is not getting enough water. Still a work in progress.