Mistakes when building raised beds.
I’ve made my own raised beds several times over, and I’ve also used raised beds made by other people. I believe there is no one single right raised bed plan suitable for everyone.
Some people need taller beds, and some prefer them shorter. Some lovely beds are built on legs, but that limits the growing space, and just wont work for others. And of course there are long beds and wide beds and all sorts of shapes to suit our unique spaces.
I used a bed for several seasons built by a man, the previous owner of the house, who was at least a foot taller than I am. He has a much longer arm span than I have. His beds, which worked well for him, were difficult for me to use because I couldn’t easily reach all the way to the center of them like he could. That doesn’t make the beds wrong, they were just wrong for me.
So with this in mind, here is my list of the mistakes to avoid when building raised beds.
Not spacing beds far enough apart
One of the things I recommend is to lay out your wood to the same size and dimensions and in the space it will eventually be. Walk around the beds to really get a feel for how you will work in the space. Make sure the bigger people in your family will feel comfortable walking around them.
Now make the space in between each bed 12 inches wider.
Once those plants start filling in, you could lose six inches on each side. Even if you are planning on planting herbs or ”short” plants, it’s hard to know what we may want to plant in the future. You may need to rotate your crops to maximize soil and sun. It took me several years to understand which of our beds are best for tomatoes and peppers, and which are better for lettuces and cole crops. They seemed to all be super sunny, until that first year crop went through a whole season.
Not only that, but you may decide at some point in the future to add a trellis to your bed. And have you planned for the width of your wheelbarrow? With room for maneuvering?
Making Beds too Wide
One of the great things about building your own raised beds is that you can size them to fit your own space. If you have a sunny spot along a fence or on the side of your house, you can make your bed narrow and long. While you can make your beds as long as you want, you should not make them too wide.
If the bed is too wide you will have a hard time reaching across to the middle of the bed to tend, weed, and harvest.
Worse, if you have to step on the soil to reach into the center of the bed, you are compacting the soil. Compacted soil is the opposite of why we build raised beds.
Your fast growing vegetables need oxygen mixed in the soil to grow well. Light fluffy soil is one of the primary benefits to having raised beds.
Your best bet is to plan in advance how you are going to use the beds so that you won’t have to walk on them and compact the soil. How do you keep from walking on your raised bed soil? Don’t make them too wide.
Not Amending Soil
Another of the mistakes when building raised beds is not amending the soil. No matter what type of garden soil you have, you want to amend it when filling raised beds. Even if you are getting soil delivered, it is still important to mix in some high quality compost prior to planting to ensure your vegetables and other plants have enough nutrition throughout the entire growing season.
Not using good quality soil will significantly compromise the health of your plants. At the very least you will notice that the vegetables grown in depleted or nutrient poor soil will grow more slowly and never produce as abundantly or get to the size of vegetables grown in nutrient rich soil.
Not lining the bottom of the beds
No matter where you live, there are critters who are going to want to get into your tender young vegetables. In my opinion, the most heinous of all are the burrowing ones, because they often come in the night time, and give no forewarning they are there. One morning you might come out to your garden and the entire otherwise healthy plant is either completely gone, or it is cut down at the level of the soil.
Moles, gophers, and voles are the worst culprits, but rats, chipmunks, opossum, groundhogs, and even rabbits and raccoons can all burrow to spoil gardens.
You have a simple option when planning out your new raised garden bed area to foil these burrowing animals. Before flipping over your raised bed frame over, line it with some metal wire. My favorite is hardware cloth. This is basically a sturdy wire screen with a square pattern. Look for hardware cloth that us no more than 1/2 inch square.
Chicken wire or poultry netting, on the other hand, has a more hexagonal shaped pattern. Chicken wire is not recommended because it can rust within a year or two, and is more easily penetrated by many burrowing critters. This is an example of the cheaper material costing more in the long run because it doesn’t last as long and you have to replace it sooner. Replacing all the soil and the chicken wire is a huge job; don’t do it more often than you need to.
Not planning for Irrigation
If you live in hot or dry areas, but even if you live in wetter areas, you should always plan to have irrigation nearby for your raised beds. The complexity of the watering system should match the weather where you are. For example, if you live where you can usually count on weekly rain, you can probably get by with just a hose or a reclaimed runoff setup, such a a water catchment basin. This will allow you to get through a dry spell or a heat wave.
However, if you live in hotter, drier areas, you should invest in a more sophisticated, plumbed system on timers with shut off valves. Even if you think you’ll be able to water daily, you might need to consider how to water the plants when you are away. A timed system ensures that the plants get the optimum amount of water at the optimum time.
Using the wrong wood
Lumber species and types have different densities and therefore have different durability when exposed to soil and water.
Generally, fast growing woods like pine are less dense and more susceptible to rot. This is why they tend to be less expensive. Cedar and redwood, on the other hand are far less resistant to rot. Over the long term, you will likely save money by using the denser wood because you will need to replace it far less frequently. How long the wood in your raised beds last depends considerably on where you live and how much sun and water you get in your location.
I do not recommend pressure treated woods. While the worst of the chemicals have been banned for about two decades, still there are other chemicals meant to kill bugs which can and do leach into your soil. When you have such a plethora of options, there’s no reason to risk the chemicals.
Not planning for plant height
No matter what you plan to plant on day one, build your raised beds as if you were putting in all pole beans, indeterminate tomatoes, Luffa or cucumbers. Bigger, taller, vegetables get very heavy and need quite a bit of support. Even if you have sturdy supports it is important to take into consideration what might happen in high winds.
Corner supports or posts are a great addition to your raised beds to secure tomato cages and other supports for those taller, heavier plants.
Not addressing pathways in between the beds
The last of the mistakes when Building Raised Beds is not addressing pathways in between your raised beds. Those pathways will get a lot of trampling, a lot of excess water, and a lot of fallen seeds. Unless you want a muddy mess with weeds and other sprouts, you need to think about those pathways.
In some areas, grass is sufficient to control weeds and water. But for most people, its helpful to build up the level of the ground between beds, install some sort of weed-block and drainage. Mulch is a great option for covering weedblock and increasing drainage. Peagravel is another great option.
These preventative measures will keep your paths weed-free and looking good for years.
