Probably the best known system of raised bed gardening is Mel Bartholomew’s Square Foot Gardening method. About 30 years ago, he began to question why “traditional” gardening is done in particular ways, especially ones that he felt were unnecessarily time, space, or labor intensive. He met with a fair amount of resistance when he would ask “Why do you do it that way?” but he persisted with his notions that gardening didn’t have to be that hard.
After years of experimenting, he wrote his original book on the topic. A few years ago, he released a newer version that he says even further simplifies gardening and almost guarantees success, even for the first-timer. In it, he explains all the reasons why he thinks raised bed gardening is a superior method. For the sake of brevity, I will try to condense them here.
Tenets of the Square Foot Gardening (SFG) Method:
1. You start with “good soil” rather than spending years “developing” it.
2. No wasted space– you don’t weed the aisles and every bit of the growing area is utilized.
3. Fewer seeds/plants needed to produce a robust harvest.
4. The whole crop doesn’t have to mature at once– you can successively plant for harvest throughout the growing season.
5. “Gardens” can be anywhere you want them, especially close to the kitchen or water source. They can be split up into many 4 x 4 sections wherever you have open space.
6. Small plots can produce lots of food. He says that SF gardens will produce as much as the traditional “row” gardens, but in 20% of the space.
7. SFG in raised beds is much easier for people with joint trouble or other challenges to be able to plant and maintain. No tilling, “double-digging,” or other difficult physical exertion.
8. Gardening could even be “portable” with solid bottom boxes that could be put on tabletops or wheels.
His points are all both interesting and promising, though I am a bit skeptical of a few claims. First, I don’t see the point in planting “space hogs” in raised beds, especially if you only have a few beds. Winter squash and melons run for 20 feet or more sometimes, so they don’t seem like good candidates.
Mr. Bartholomew says you should trellis them, but the supports would have to be mighty high, sturdy, and well-anchored to support those heavy fruits. Then they would cast a lot of shade on whatever you may have wanted to grow to the north of them. That could be used to your advantage, but you’d have to plan ahead. Sunflowers would have to be planted in the northern most box and one box would not accommodate many plants.
Corn and beans also need quite a bit of room if you want to get more than a couple meals out of them. Our goal is to grow a surplus for storage, not just a sampling for the summer. For this reason, we plan to reserve the new raised beds for smaller more productive plants and put the “space hogs” and “skyscrapers” in the old garden space. I hope to use the Three Sisters method of companion planting to reduce the need for fertilizing and weeding. Flowers like zinnias (our little ones love to grow them) and sunflowers will probably get spots there too.
Mr. Bartholomew has a very specific recipe for what should go into those raised beds. His “Mel’s Mix” calls for 1/3 peat moss, 1/3 compost, and 1/3 coarse vermiculite. He insists this is key to success. Simplified, the peat moss holds moisture, the compost provides the nutrition, and the vermiculite keeps the soil light so there is plenty of room for root growth. (In addition, you never step into the beds or otherwise compact the soil).
I’m sure he is right about the benefits of using this particular mixture of soil. Practically and economically speaking though, it’s not that easy to create.
Four cubic foot bags of peat moss is readily available in most garden areas of stores. The rest is is pretty tough. His prescription requires 5 different kinds of compost (for example, compost from mushrooms, cow manure, plant waste, etc.) I haven’t found any one place that carries that many types. (If you are not sure of the origin of the “organic humus,” read the fine print on the bag- I am finding that what big box stores carry locally is mostly waste from the factory farming of chickens- manure, “feather meal,” etc.). The reason for the mixture of compost types is so that the nutrients provided will cover the gamut of the plants’ needs. If all the compost if from one source, it will be unbalanced.
In addition, I am finding vermiculite in the amounts I would need to be exorbitantly expensive if available at all.
Mr. Bartholomew also insists that the beds be divided physically on top with some sort of lattice work to make individual “square feet.” In his method, every SF should be planted with something different. These are details I don’t feel inclined to fool with. With some things like radishes, I probably don’t want more than 16 maturing in a week or two’s time because I would only be using them for fresh eating. Many other things (like pickling cucumbers and tomatoes for sauce) I would need many of at once.
Since I have had trouble locating vermiculite for a reasonable price (even online) and it doesn’t offer any needed nutrients, I think we will have to proceed without it. I have only been able to find 4 types of bagged commercial compost, but we have our own to add from the rabbits, kitchen waste, etc.
Overall, I am looking forward to (mostly) trying this new way of growing food in raised beds, but with the difficulty and expense to get started, I’m not sure I can go so far as to “recommend” it yet. Preparedness-minded people always have to make careful decisions about how and where to spend their money. Though I realize these beds should be seen as a long-term investment that will pay dividends in years to come, they are a bit pricey to get started with, at least if you go by Mel’s prescription.
I’ll let you know how the season goes and pass along any lessons we learn along the way. Please share your own experiences too.