Looking around the San Francisco Bay Area these days, raised beds seem to be everywhere. We couldn’t be happier. The Slow Food movement and increasing interest in growing our own food has made them a valuable tool in a lot of local gardens, where the soil is, well, awful. It can be devoid of organic matter, which is a requirement of successful edible gardening. As an avid gardener myself, I spend a lot of time wondering what happened to all my topsoil. How can soil erosion be that bad on a relatively flat lot? And why I don’t start my own pottery business since everything I turn out of the ground is CLAY? Trying to establish plant roots in that environment feels like fighting a losing battle. How can you make the most out of your garden space and ensure that your soil has necessary organic matter?
If you want to grow your own, raised beds could be the answer.
Having your vegetables above ground means control- not easy to come by when you’re dealing with Mother Nature. You can more easily address pest or disease issues. You can handpick the soil and amendments that are most appropriate for what you want to grow. Based on the height of your beds, you could potentially eliminate crouching, kneeling or stooping to harvest or weed- which we all know can be tough on our backs & knees. Further, you aren’t limited to growing areas defined by your existing garden layout. You can install raised beds on top of stone, concrete or gravel patios, decks, some roofs, even along asphalt driveways. In smaller gardens, this ‘square foot gardening’ tactic can create a layering effect utilizing both edibles and perennials to make the most of your space.
In my garden, a large section is partially shaded by Pittosporum trees. Not much sun is a problem I can handle. But the soil underneath is full of tree roots, devoid of nutrients and hard as rock, even in winter after substantial rains. My solution? Raised beds. The soil in my raised beds is ideal for my plant roots. I’ve found a few vegetables that can thrive in part shade (Kale! Radishes!) and even customized my beds by painting them, creating a colorful backdrop in the darkest part of my garden.
So what else can raised beds do? Designed properly, raised beds perform double duty: a wall of your bed can serve as a retaining wall, preventing soil erosion while providing ideal soil conditions for growing vegetables, perennials and flowering shrubs. We all know that planting can help control soil erosion, and if you construct a structural wall to delineate the back of a raised bed, you can reduce the possibility for soil erosion even further. For those of you with steep slopes, disturbing the soil or existing planting can actually increase the chances of soil erosion. Carving out an accessible area to focus planting with a combination retaining wall & raised bed leaves the remaining slope above undisturbed, and create a flat space below for you to easily access your beds, relax, and enjoy the view.
There aren’t many. Installing raised beds can be more costly than planting the old fashioned way (i.e. holes in the ground). But even with extensive soil amendment in traditional planting, essential nutrients will eventually leach out of the compost and the soil will revert to its prior condition. With raised beds, you can replace or amend soil with organic matter much more easily. We’ve done a lot of planting at Lazar Landscape in the last 30 years, and have seen firsthand the amazing difference in growth rate with plants grown in native soil versus raised beds. Plant roots are so much more easily established in the nutrient rich, aerated soil of raised beds, and the resulting growth can be spectacular.
You don’t have go strictly edible with raised beds either. We recommend mixing perennials with your edibles. There are many colorful perennials that are not only beautiful, but attract beneficial insects to help you combat pests. They create a cool contrast to leafy greens, bold squashes and sweet strawberries. They also keep portions of your beds looking pretty when you’re changing crops, as recent harvests can leave all-vegetable beds looking a bit sad. As many of you Bay Area gardeners have discovered, a kitchen garden featuring fresh herbs is wonderful to have on hand. Added bonus? Deer and gophers leave Rosemary, Thyme, Sage, Chives and Parsley alone. On that note, individual beds are much easier (and less expensive!) to protect from wildlife than a whole garden. Simple welded wire screens over or around raised beds can keep deer and gophers out, not to mention raccoon, squirrels, birds, or Tucker (my neighbor’s Springer Spaniel. He likes to dig around my sweet peppers).
Not interested in an urban or suburban farm? Raised beds aren’t just the realm of vegetable gardeners. There is a raised bed for any garden style. Raised beds can be built out of concrete, brick or stone- whatever style best suits your garden aesthetic. The important things to remember are making sure your beds include appropriate drainage, and if you are growing edibles, you should steer clear of pressure treated woods- the metals used to treat the material can leach into your soil, and your edibles. This is a great time to get started. Have questions or need help with your own raised beds? We’re here!