Barrel gardens are really good at two things compared to other gardens:
1. Reducing water consumption by catching excess water that can be reused.
2. Cramming a lot of plants into a small space.
Being an apartment dweller that second point really sealed the deal for me. I LOVE spending time outside gardening, but I simply do not own any land. A barrel with pockets is a great way to get my gardening fix in a small package. This design gave me the opportunity to have a garden in my 'backyard' where I otherwise would not have been able to have one.
This particular barrel garden design is multi-functional. As you can see, the stand it normally sits on can also be used to cover the barrel making it into a stool and place to store your gardening gear in the off season.
Many barrel gardens have a pipe section placed in the center as a composting bin and home for earth worms. I decided that this addition was not worth the extra trouble of adding it nor the added time spent using & cleaning it out. Composing is messy work.
This project has actually been a year in the making. Most of the photos shown are from my garden last year, but the cool thing is that now I have photos of the beginning & end of the garden as well as some return on investment calculations to show for the project. I've since moved to a new apartment with an inadequate deck and have had the barrel in stool mode ever since.
Since I'd like to do a little gardening this year I decided to design an even smaller version: A 3D printable herb garden pot! This model has been printed and verified to function as intended.
NOTE: I am not a professional gardener by anyone's definition. This is something that I enjoy and have experimented with a bit, but there are still many gaps in my knowledge of gardening. Please feel free to leave your own ideas for improvement on the barrel design, plant choices, soil composition, or whatever!
Step 1: TOOLS & MATERIALS
Drill (for stress relief holes, drain holes, assembling the stand)
Heat Gun (for softening the pockets enough to open them)
Sawzall or Jigsaw (for cutting open the lid and cutting the pockets)
Empty Wine bottles or flat prybar (for prying open the pockets)
Heavy work gloves (to prevent burning yourself)
Barrel: Any size will work, standard plastic drum sizes are 50 gal, 30 gal, 15 gal, & 5 gal bucket.
Your best bet for a cheap big barrel is going to a car wash and asking for an empty one. (I won't even provide a link for getting a new one online because the shipping cost is obscene.)
Plastic Spray Paint: I've read that plant roots prefer to be in the dark so I spray painted my translucent barrel into a tan color that matched my deck. My 30 gal drum & stand took a total of 3 cans of Krylon, which worked well on the polyethylene drum.
(1) 2" x 4" x 6' board: To be cut to lengths as shown on a later step.
(1) 2" x 3" x 6' board: To be cut to lengths as shown on a later step.
Optional: (1) 1/4" x 24" x 24" plywood sheet: For covering your stand to make a stool
Step 2: WASH BARREL
If you were able to recover a barrel from an industrial site like I did then you REALLY need to wash it before using it for gardening. Just give it 5 minutes at a self service car wash.
Step 3: CUT OPEN LID & DRILL BASE DRAIN
Make a hole in the lid so you can stick your saw blade through. Then cut out the top as shown in the pictures. DON'T cut off the outer lip though, as this is what keeps the barrel strong.
For the drain just drill a couple dozen 1/8" holes in a tight circular pattern in the center of the base.
Step 4: CUT POCKETS
I've provided the dimensions used on my 30 gal drum, but don't be afraid of making a few measurements and doing a little math of your own. You can't go wrong if you make all your marks with a sharpie before cutting anything. Remember to stagger your pockets with every level. If you were going to do a 50 gal drum, I would probably go with 4 tiers of pockets.
Drill a 1/2" hole on each side of the slot so you can get your saw cut started and to relieve the stress of being stretched.
Step 5: FORM POCKETS
Be forewarned, this step is a lot of work!
Use your heat gun on high to soften the plastic and your prybar & wine bottles to open the slot and keep it open until the plastic cools. (Don't use a 2x4 to pry with or you will tear the pockets!) Always keep the heat gun moving, never stopping, in a triangle/diamond motion from the slot to about 5 inches above and below it.
After the pockets are formed and the barrel is cool you can paint it.
Step 6: BUILD STAND
See attached pdf for stand dimensions.
The optional 1/4" plywood sheet is only added if you want to use this as a stool. I got the square pillow from Lowes.
Step 7: PLANT!
My soil mixture was:
30% bagged manure compost,
60% bagged garden soil with integrated long term release fertilizer,
10% natural compost I had available (a substitution for peat moss).
Fill your barrel all the way to the top with soil. Keep a bit of extra soil on hand after you pot everything because the soil will gradually compress and leave a sink hole in the center that you will want to refill.
Seeds are really really cheap to start a garden from if you have the patience. Even so I always end up buying the 3" tall pre-started plants from the hardware store.
Barrel gardens work best with small plants that don't sprawl too much, but I still tried to put tomatoes in the top area. In retrospect I would have been better to put fewer plants in the top so they wouldn't compete for light and would end up being stronger. I also found the wooden support stakes to be very useful to keep the plants growing in the orientation I wanted.
My garden was in an inescapably shady area: under an awning facing northeast...!Honestly I should not have put a garden where I did. Even so my kale, lettuce, & stevia plants went nuts. The jalapeno peppers are pretty robust plants so they did well enough, though they would have liked more light. Forget the strawberries if you plan on refreshing your soil annually (they are perennials and do much better on the second year).
Step 8: ROI Analysis, Accessories, & Thoughts
Just for fun I tracked my costs and the garden's food output to evaluate the potential return on investment. Obviously the first year is the most expensive because you incur all the one time costs for the barrel, stand, paint, in addition to all of the annual costs. Recurring annual costs will be for seeds, new soil, fertilizer, etc.
*I spent an actual total of $60 for everything including the gutter garden accessory because I had some things on hand to start and I'm scrappy.
*If I had started with absolutely nothing then everything would have cost about $200, with $40 of that being a recurring cost annually.
*The total cost for the gutter garden pictured was $20 (included in that $200 above), and it worked well enough for the lettuce & flowers. Although it did tend to dry out quickly and it didn't hold very much soil.
*Produce is generally pretty cheap, but I think if you have more access to sunlight and more gardening experience than I do then you should be able to make it pay back 100% in the first year, having said that my results were.......
**My total estimated value of harvest was a pitiful $42.75.
I couldn't help but be a bit disappointed that I didn't get more out of the garden, but after some reflection I realized that I would do the project again all the same in the end. Not everything is about money. Gardening reduces my stress level, gives me a much desired connection to the outdoors, and is just plain fun regardless of the financial costs and benefits involved.
As it happens, while working on this garden I was also reading a book about another man's gardening troubles and tribulations that lead him to the very same conclusion as me. I 100% recommend this book as a fun nonfiction read: The $64 Tomato: How One Man Nearly Lost His Sanity, Spent a Fortune, and Endured an Existential Crisis in the Quest for the Perfect Garden
Final note: This instructable was created for both the Backyard Contest and the 3D Printing Contest (see the 3D printable herb garden pot in the first step if you missed it!). If you have enjoyed my work then please let me know and vote for this Instructable! Also, constructive ideas for improvement are always welcome!