Editor’s Note: This is a guest contribution as part of our Sustainability Scavenger Hunt series. Read more here, and download the fun activity book for families and classrooms!

by Renee Frederick, urban farmer and educator

The seed catalogs have started showing up in the mail, reminding us planting season is right around the corner. I’m choosing from the winning varieties that I saved from last year and a few new compact varieties that will work well in my barrel garden. This version of a vertical garden is perfect for community and school gardens, apartment dwellers, or for those who want high yields with minimal maintenance and space.

I started building vertical gardens for classrooms in Milwaukee when looking for good ways to teach students about composting and the food cycle. As a hands-on learning tool, these vertical gardens have a lot to offer. They’re a great example of re-using old materials (55-gallon barrel), a perforated PVC pipe runs down the center of the barrel, housing composting Red Wriggler worms, and each of the 42 pockets can house a wide variety of companionable produce. Students have a lot of fun sorting through the finished worm castings, pulling out the cocoons and learning more about how nematodes and other critters can be beneficial to soil health and plant productivity.

When I moved back to Madison, I put my barrel garden in the front yard to avoid the black walnut trees of the backyard. There is just enough space with good sunlight for one barrel, but yield per square foot is incredible. A single barrel garden provided enough produce that I put up a sign for the public to share in the bounty! Many of my neighbors were impressed with the yield, and I was happy to share the plans with them.

The system requires minimal inputs. It requires less water than conventional gardens because there isn’t much soil surface area for evapotranspiration (loss of water from soil by both evaporation and transpiration from the plants growing in the soil). The lack of surface area means there is no need to set aside an afternoon for weeding; simply pull the stray sprouts out while harvesting some parsley for dinner.

Barrel gardens don’t require additional fertilizers because the Red Wrigglers do all the hard work. The plants’ roots extend toward the center of the barrel, where the worms turn coffee grounds and carrot peels into “black gold.” Adding shredded newspaper with my food scraps keeps the worms happy and healthy all summer long. Once the growing season is over, cleaning up is a cinch. Pull out the remaining plants, remove the cap and empty the PVC pipe to collect the worms for over-wintering in the garage or basement.

After a few years of vertical growing, it’s hard to imagine growing herbs, lettuces, and cherry tomatoes any other way. If you’re interested in building your own barrel garden, send me a note at renee.a.frederick@gmail.com and I’ll gladly share the plans with you.


Renee Frederick is an urban farmer, graduate of the University of Wisconsin – Milwaukee, and compost fangirl. She resides in the Madison area and works to connect students with their food. If you’re interested in barrel garden designs, she can be reached at renee.a.frederick@gmail.com.

All photos by Renee Frederick and used with permission.