My friend Susie and I love to garden, grow things, preserve and nourish. We were recently scouting out different greenhouses and she mentioned that she was considering raised beds in the future instead of planting a traditional garden. I have also toyed with the idea so I wanted to research some of the pros and cons.
Raised gardening beds are more than just adding more soil to rows in a garden. Quite simply, they consist of walls made of various materials surrounding soil with vegetables, herbs and flowers planted inside the structure. They are also known as garden boxes and framed beds.
Perhaps the biggest pro for raised beds is that you can make them as high off the ground as you wish and this prevents so much bending over or crawling on your knees. Some other pros to raised beds are:
- Raised beds can be as compact or as large as desired to fit any backyard or city lot. They can also be placed anywhere, regardless of the soil type. This is especially important if you have poor soil or contaminated soil. Since you add your own planting mix, it makes no difference what the bed sets on.
- They allow people with disabilities or who are less mobile to garden because tending to them is less strenuous.
- The soil in raised beds warms quicker in the spring than garden soil does, allowing for earlier planting and subsequent earlier harvesting.
- In areas with heavier soil types like clay, raised beds will drain better and soil will dry faster for planting. However, this can also be a two-sided sword because if they drain faster, they will also require more watering during the season.
- With more than one raised bed, each one can be filled with different types of soil and different fertilizers and nutrients can be used and matched to the different crops. Since the soil is contained, these beds may also help to concentrate the compost and fertilizer and keep them from being washed away. Especially if your garden spot is on rolling or hilly ground, raised beds can prevent erosion.
- Bottoms can be screened to prevent gophers, moles and other critters from wreaking havoc with your crops.
- On the same note, they keep kids and pets from stepping on plants.
- Gardens look neater, soil is kept in place and pathways are kept cleaner. Yes, this is a benefit but there is also a downside here. You trade off cultivating for weed eating around the beds. Personally, I like the look of a well-rototilled garden.
Now for the cases against raised beds:
- Unless you use the same dirt that is in your garden now, you have to buy dirt whether you choose top soil, peat moss, a mixture or something else; there is still an expense involved.
- Add to this the expense, in both money and time, to buy the material and build the raised beds.
- Soil dries out faster, which was pointed out as a good thing if you have clay soil, but in sandy soils, this is definitely not an asset. Because of this, raised beds usually require more watering.
- They are less sustainable because of buying and transporting the soil and walls.
- Since soil warms faster in raised beds, it is good in the spring but summer’s heat may be a problem for some plants. On the other side of the coin, the beds also cool down faster in the fall.
- They may actually require more space since the runs between the beds have to be wide enough to accommodate wheel barrows and other equipment.
- Drop irrigation is harder to install.
- Perennials have to be hardier because raised beds get colder in the winter.
- They restrict root systems on plants like tomatoes where roots grow several feet in all directions.
- Squeezing more plants into a tight space reduces air circulation and increases moisture levels which increase the risk of diseases.
- Building materials are restricted because you want no chemicals that will leach into the soil.
On the subject of building materials, the best ones to use for the walls of raised beds are redwood or black locust lumber because of longevity and natural rot-resistant traits. These woods have been known to last up to 20 years with cedar a close second, withstanding the elements up to 15 years. As an added bonus, cedar looks gorgeous and fits most any landscape.
Concrete and masonry are definitely more permanent but is more costly and is harder to remove if you ever choose not to have raised beds anymore. Cinderblock is a middle-of-the-road option. It can be mortared for longevity or just stacked, making it easier to remove. Natural rocks are always an option, especially if you already have them on your property because cost doesn’t get much cheaper than free. The downside here is that weeds will eventually creep in between them.
One of the latest trends is to use galvanized culverts, sliced in sections in the length that you want your height to be. Galvanized stock tanks also work well. Both will never rust and look good with any landscaping.
The types of material to definitely steer clear of is treated wood. This includes creosote-soaked railroad ties. Eventually anything with chemicals in it will find its way into the soil.
Taking the raised beds one step further is the square foot gardens that have found some fame as of late. These are basically raised beds that have been divided into perfect squares with each square holding a single variety of plant. These look well groomed and are ideal if you are limited in space. However, they are not ideal for crops that need a lot of room such as squash, cucumbers, melons and other plants that like to vine out. They make great containers for herbs.
Before you decide to go the raised bed route, be sure and check all the conditions for your particular area such as how much rainfall you usually get, what type of soil you have, what you plan on growing each year, etc. All of these reasons listed, both pro and con, have nothing to do with higher productivity, better flavor or nutrition. When raising plants, dirt is dirt.
Whether you choose to go the raised bed route or not is a matter of personal taste. Like so many things in life, it boils down to what is best for you. As I get older, having raised beds may entice me a little more. As for now, I love to see the old-fashioned rows in a garden and to dig my toes in the sun-kissed dirt while I work the soil and watch the plants grow. There is nothing better!