Raised beds offer the best way to control soil composition and drainage
I’m often asked about gardening in raised beds. It’s one of the best ways to grow productive and healthy plants and given the option, I’d choose raised beds every time.
I attribute much of the success experienced on the set of Fresh from the Garden to building raised beds for the vegetables I grew. They allow for better control of drainage, the opportunity to create custom soil conditions, a defined planting area, and a more user friendly work area, just to name a few of the benefits.
Although raised beds can be as simple as mounding up soil into a deep wide planting area, I’ll address those with physical borders for this discussion. Here are some things to consider when building your own:
Material
Anything to retain the soil works, from scrap concrete to lumber to railroad ties, etc. Even composite wood, made of recycled plastic and wood fiber are becoming more popular.
I prefer non-treated, rot resistant lumber such as cedar. Pressure treated wood is less expensive and readily available but there is some debate around the safety of its use, especially if using these beds for edibles.
Height
I have had excellent success with beds that are 12″ tall. This gives plant roots a great environment for expansion and growth. However, a 6″ bed height is adequate if your soil is well amended. Some raised beds are even a back saving waist high to minimize bending over. As long as the soil is well amended, anything over 6″ is a bonus.
Length and width
When building raised beds, length is completely optional and limited primarily to your physical space. Width on the other hand is more important. Beds should be wide enough to allow for at least two rows of plants. Three rows are desirable in many cases. However, don’t make the bed too wide to prevent being able to reach into the center.
All the beds on the Fresh from the Garden set were 12’ long and 3’ wide. The plants grew well and I was always able to plant at least two rows across. However, I think a bed that is 4’ wide is ideal and provides even more planting options.
Other considerations
When using flexible material such as lumber, the pressure of the soil will cause the wood to bow out. You should provide staking half way down the length and secure the wood to it to prevent this outward bowing.
If using wood, build the frame so that the wood grain on all boards is facing inward. Otherwise, they may pull away and curve toward the outside as the wood dries and weathers. Not only is this unsightly, it can pull the screws or nails out as well, making your beds less secure.
Speaking of screws, I prefer them over nails for securing the wood. Screws are forgiving if you make a mistake but be sure to use all weather wood screws with a length of at least 3″. To prevent splitting, it is a good idea to drill pilot holes first; especially towards the ends of each piece.
Pre-made kits are now readily available that include connecting joints and hinges so you can configure your bed shape and height just about anyway you’d like. These devices make bed setup a snap and no construction is required. When it comes to simplicity for raised bed construction, these kits are ideal. You can find them through many catalog and mail order garden supply companies.
If you really want to have a beautiful and productive garden, give raised beds a try. They’ve never been easier to make and the advantages for you and your plants are numerous. Even better, they’ll be there waiting on you season after season. What could be easier?
About Joe Lamp'l
Joe Lamp'l is the Host and Executive Producer of the award winning PBS television series Growing A Greener World. Off camera, Joe dedicates his time to promoting sustainability through his popular books, blog, podcast series, and nationally syndicated newspaper columns. Follow Joe on Twitter
I would like to send some garden and raised bed pictures to Joe for review. What is the best way to send these pictures?
If you are a member of the Joe Gardener group you could post the photos and share them with the group.
I built my raised beds out of regular lumber. Is it ok to spray the outside of the raised beds with latex paint or leave them as is with the regular lumber?
Larry, Joe recommends not spraying the outside with paint but leaving them as they are. This way they will be able to breathe.
Enjoy your raised beds. For more information, I highly recommend you listen to Joe’s podcast series on raised bed gardening. There are also extensive notes that accompany each podcast. Here is a link for part one. https://joegardener.com/podcast/raised-bed-gardening-pt-1/
What size lumber are you using?
Nickalaus,
Here is a link that will give you the specific information about the size of the lumber( as well as a diagram) we used to build the raised beds at the Garden Farm. https://www.growingagreenerworld.com/raised-bed-garden/
I watched your show where you built raised beds with supports for the wood slats that were x-shaped and you said they were actually for another purpose. What are they called and where did they come from? They were stackable.
Vicki, I believe the supports you are talking about are concrete corners called Builders Blocks and we got them at Home Depot. Good luck with building your raised beds. I know you will enjoy all the benefits they offer. Happy Gardening!
Can you use commercial much say like from Lowes or home depot?
I have a friend who owns a saw mill.
Can you use mulch from this sawmill?
If so, which type works best?
Pine or oak?
Larry, If you use mulch from a big box store, I recommend hardwood mulch, either shredded or nuggets. I would stay away from colored mulches. Sawdust is ok, but only as a mulch, not as a soil amendment. Because it is so fine, it may repel water. If you use drip irrigation this would help. I hope this helps. Happy gardening.
Hey Joe
Do you use Mulch in your raised beds?
Larry,
For mulch you can use shredded leaves, arborist wood chips or straw. There are many options. When the wood chips and shredded leaves break down they provide a wonderful soil amendment.
I am going to build my own raised beds. They will be 4 feet wide 10 inches high and 8 feet long.
How many tomato plants can I grow in these beds using the cattle panel tomato cages?
Thanks for your help.
Larry, Make sure to give your tomatoes (including the cages) plenty of space, I would recommend planting them on at least 2′ centers, but this also depends on the variety of tomato you are growing. The video and the blog post should help you with all the particulars. For 12′ long beds, I used four tomato cages.
https://www.growingagreenerworld.com/ultimate-tomato-cage/ and https://www.growingagreenerworld.com/best-tomato-support-criteria/. Best of luck and happy gardening!
How much space do you need between each raised bed ?
For example: Space enough to walk easily between each bed and each row .
Larry,
How much space to leave between raised beds is a good question. Think about working in your garden and getting supplies in.
You may want to leave (I recommend) enough space to bring in a wheelbarrow or a garden cart either between beds or at both ends of the garden.
This will also allow for better air circulation. Good luck with your raised beds, I know you will enjoy all the benefits they offer.
I see the note about using pressure treated lumber for raised beds. Bottom line, can we, should we use that in our beds??? All the product in those beds are edible.. Cant find suitable non treated lumber that will either last, or I can afford. So what do you say>
Richard,
For growing vegetables, it is safest not to use pressure treated lumber. Some alternatives
include red cedar or redwood. Heartwood will last longer than sapwood if you have a choice. Stones or bricks are another option to consider and will last indefinitely. Best of luck.
We are building raised beds this year for our vegetables. Will let you know how it turns out.
I need help in putting together raised bed boxes atop concrete blocks? Testimonials and suggestions welcomed! God bless.