Brief Overview: Wood & Steel hybrid raised beds
Becoming more popular is using roofing paneling in combination with the supporting structure made of lumber. There are many ways to do this, however generally the wood structure contains the panels that retain the soil.
one can assume with the proper type of wood; these beds can last a significant amount of time. The lifespan of these beds seems to be increased over lumber only beds because the lumber isn’t directly in contact with the moist soil conditions. The galvanized roof panels are said to be good for 25-60 years in a roofing application, so it’d be conservative to predict they could last 15 years in a garden bed in my opinion, of course this can be reduced depending on conditions like crushing the bed without your skid-steer or tractor bucket.
Figure 1: 2.2′ tall beds using 2 x 4s and galvanized corrugated panels.
This is another win for this type of bed. For typical height raised beds (10” – 12”) you can get away with using 2 x 2 lumber or even ripping normally 2 x 4s in half which will come in closer to 2 x 1.75 if it’s not true dimensional rough-cut lumber. (Seen in figure 2) The steel panels were purchased at the time for $15 each. (The 12” tall bed only requires 1.5 panels that measured 8’ by 2.2’) As you can see in figure 2, I ran out of steel corrugated panels and used scrap PVC panels on one short side. It may not last as long on that side, but it saved me from buying a whole panel to only use 1/4th of it. You could really save some funds if you were able to find listings for someone selling affordable reclaimed barn roof or even steel roof panels from residential roof jobs, in some cases you may even find panels completely free.
Figure 2: Wood / Steel hybrid bed using ripped 2 x 4s and galvanized corrugated panels.
So, what’s the appeal?
Some may cringe with disgust at the look of steel panels whether they are powder coated or galvanized, however for those who are neutral or even enjoy them there is one major benefit these beds have over other types of raised bed construction. Affordability to build for height! If you were to build a 2’-3’ or higher raised bed from normal methods with lumber or even masonry, the expense and labor would quickly multiply the higher you went. This fact coupled with the lifespan covered earlier makes these beds a real viable option for your garden or farm.