As you shoveled snow this week, did you rediscover that digging is hard work? Did your back complain that you’re not getting any younger? No matter how much we love gardening, the truth is that digging into heavy soil is strenuous for everyone. In this region most of us have clay soil, compacted soil, or both. If you plan a flat, in-ground garden, then you probably have to break up the soil, turn in lots of compost and dig holes or trenches for planting.
Fortunately, there are easier ways.
Raised bed gardening
There’s nothing new about gardening in containers or raised beds that let you grow plants above the level of solid ground. Ancient civilizations invented several ways to plant into mounds. An old German method referred to “huegels” or hills built with coarse sticks and brush at the bottom and layers of organic materials piled on top. Organic farmers, who place high value on soil tilth (friability) and soil life, typically employ wide row and raised bed methods. Old or new, these methods provide the same benefits:
• Prevent soil compaction
• Avoid repeated digging in heavy soil
• Control of soil quality
• Easier planting, weeding, harvesting
• Efficient, intensive use of soil
• Portability: Some raised beds can be moved
In gardening trade shows, garden centers and in gardening courses you can learn techniques and find products that make gardening much easier as they let you build up rather than dig down.
In trade shows in California, Florida, Boston and locally, one product line has impressed me at every turn: The Smart Pot line of products, including the Big Bag Bed. Smart Pots are basically fabric bags, with or without handles, that come in many shapes and sizes. They may be hung from a fence or placed on a flat surface. The Big Bag Beds are typically round, wide, low beds that you place on top of the ground as instant raised beds. In all these cases, just provide your own potting mix and you can grow anything. I observed them in Quebec City and in our own Broadway Market rooftop gardens. They will be seen on driveways, decks, and in front or back yards wherever gardeners want to grow with minimal bending and digging.
Other choices for container gardening include any clay, plastic, or wooden containers – with drainage holes of course. Another outstanding product is the Earth Box, which even has a self-watering system.
All these container or raised bed forms do need to be filled with potting soil and I will reiterate: In containers, the health and quality of the soil mix is critical, so buy potting mix from a reputable source, and don’t just dump in your outside soil. Many nurseries offer good compost/topsoil mixes for raised bed systems. I have used and appreciated the quality soil mix in the Big Yellow Bag from Lakeside Sod, a local company, which can be dropped off in your driveway neatly and conveniently.
Build it yourself
If you’re handy and can hammer or haul things, you can build your own raised beds. As you decide on the size, some general wisdom applies: A raised bed should only be as wide as you can plant into and tend from the side of the bed. If you have to step in it, you’re compacting the soil and defeating the purpose. So 3 to 4 feet wide is about right. The bed can be as long as you want, but consider the practicalities of walking around it.
As for depth: If the ground you’re building upon is cementlike, contaminated (or actually cement) then you need to build the bed high enough that plant roots have enough depth of soil – perhaps 15 inches for small flowers and salad greens, three feet for shrubs or tomatoes. If the soil is just poor, then break it up coarsely and build a bed 15-inches high, knowing the roots will reach into the old soil. (When I mention depth, I’m referring to the soil depth; therefore the actual sides of the bed might be slightly higher.)
With dimensions in mind, decide what you have or can get for enclosing this bed. Large rocks are picturesque. Cinderblocks are practical (although you may have to check that they don’t raise soil pH). Plastic kits are on the market. Old telephone poles used to be popular but creosote leaching was discovered, a threat to health. Logs are viable choices, although they will decompose in a couple of years. I have seen gorgeous raised beds gracefully encircled by fallen tree limbs and trunks. Even if they decompose around the garden bed, it is a natural and attractive process.
Most people use boards, which should be as hard wood as possible. In my book, “Great Garden Companions,” I showed pictures of building my raised beds with hemlock boards, and those beds lasted 12 years. I recommend ∫-inch thickness or thicker, as thinner boards warp or decompose sooner. (Formerly we used treated wood until we learned about formaldehyde.) If you use wood for raised beds it’s a good idea to line the inside walls with heavy builder’s plastic or gardening black plastic, to slow the wood decomposition. If you are hammering beds together out of lumber, take care to brace the corners, as weather will pull at flimsy construction. Or build seats across the corners. Creative designers have made metal corners to connect boards for easy-to-build raised beds.
What will work for you this year? You have time for some planning and browsing. Go to the shows. (The Home and Garden Expo is in Hamburg, Feb. 25-28. Plant WNY’s Landscape and Garden Show, Plantasia, is March 31-April 3. Or travel to a flower show such as the Philadelphia Flower Show, March 5-13). Evaluate the products and tools, and hear from vendors or lecturers about ways to garden easier and with better results. Raised bed and container gardening are simply smart. Plan ahead. You and your back will be glad you did.
Sally Cunningham is a garden writer, lecturer and consultant.