Building a Herb Garden Raised Bed
Using a raised bed to grow your herb garden will make the tending and harvesting activities much easier. There are many, many variations of the basic design that is detailed in this article. This is a very simple design and you can extend or shorten the length of the sides used in this design as you see fit. I would not adjust the width of the design. It is purposely designed to be 39-1/2”for a very important reason. The width allows you to work from both sides with a reach of just 18”, which is very convenient when you are working on planting, cultivating, weeding and harvesting your herbs.
You will construct the two side units and the two end units first.
- Cut the TOP rail (2), the DECK rail (2) and the BOTTOM rail (2) for the SIDE units to a length of 92-1/2”. That is a total of 6 needed at this length.
- ü You will need 4 lengths of 2×4 cut to 24” in length. For the SIDE rails. And Cut the TOP rail (2), the DECK rail (2) and the BOTTOM rail (2) for the END units to a length of 32-1/2”. That is a total of 6 needed at this length.
- If you are using exterior or marine grade plywood to form the outside of the four units cut (2) to 24” x 96” for the side units and (2) to 24” x 96” for the end units.
- Refer to the EXPLODED VIEW for detail on the layout of the items needed to construct the sides and ends of the unit.
The dotted lines indicate where each rail is attached. Use 1-5/8” galvanized deck screws to attach each rail. I used Exterior grade Gorilla glue in addition to the deck screws for each of the rails. The DECK rail is attached with the top edge 9” from the bottom of the plywood side panel as show below. All the other rails line up with the outer edge of the plywood panel. That will create a 15” deep compartment for you soil, which should be deep enough for most herb plant needs. The following illustration shows the final layout of each of the rails.
The next step is to construct the raised bed using the (2) SIDE units and the (2) END units. Assemble the units as shown on the ¾ View using 3” or 3-1/2” galvanized deck screws. I used the exterior grade Gorilla glue along the edges for added strength.
Assemble the unit with the END panels inside the SIDE panels as illustrated in the ¾ VIEW that follows. It is recommended to assemble the unit on a level area such as a driveway or in your backyard. It will make final placement of your unit much easier in the long run. The ¾ view has the last side panel removed so you can see the partial assembly of the unit.
Once you have assembled the 2 SIDE units and the 2 END units into a box you will need to finish construction of the deck bottom as shown below.
Cut (2) 2×4 cleats 39-1/2” in length to keep the bottom of the unit from bowing out when you add the soil to the unit. Attach the two cleats as shown approximately 32” from each END unit. Use 3-1/2 galvanized deck screws to attach the cleats to the BOTTOM rails on each side.
Cut pressure treated deck material to 39-1/2” and attach to the DECK Rails with appropriate sized galvanized deck screws, as shown in the illustration below.
Notch the two end deck planks as shown to fit into the corner of the unit. Attach to the DECK rail on the SIDE & END units as shown below using appropriate length galvanized deck screws.
Once the deck planks are assembled you are ready to place the unit in its final location. It is best to install it in a level area of you backyard. I would recommend
that you drill several ¼” holes in the deck planks to facilitate drainage. I drilled them in the very center of unit about every 6”.
At this point you can add trim to the unit if you want to dress it off. I used 1”x6” pressure treated lumber to create a top ledge around the unit. That gave me a larger top edge to place pots or garden utensils on when I was working on my plants.
Once you have accomplished this task it is time to fill the unit with planting soil. I used a mixture of prepared topsoil I bought from a local garden center with Miracle Grow planting mixture. I used a ratio of two parts topsoil to 1 part Miracle Grow and it gave me an ideal consistency.
After filling the unit about ½ full I installed a drip hose around the perimeter of the unit. That hose is attached to a time that waters the herbs regularly to insure proper water distribution. I drilled a hole in the END unit just below the TOP rail to feed the hose outside the unit. I found that this system eliminate having to guess when to water and this is much easier to create a good root soaking rather than using a hand held hose which is not as efficient.
Now you are ready to add your herbs to the raised bed and begin your delicious journey raising fresh herbs for use in your culinary efforts.
This is a very basic raised bed for your Herb Garden. You can adjust the dimensions to suit your planting needs.
In the MEMBERS ONLY area there are plans for a U-shaped planting bed that I use in my garden area. For information on how to access them go the navigation menu bar above this article and click on MEMBERS LOGIN.
If you want to construct several of these units you can arrange them into a U shape or T shape. In the MEMBERS ONLY AREA of www.herbinfosite.com you will find a detailed PDF similar to this one for a custom U-shaped unit that I have in my backyard. That unit is similar to the following picture
This unit is commercially available at some custom garden centers or SAMS Club. My unit is similar but I made several adjustments to the size and layout that result in a much more productive herb garden. If you construct it from scratch you can save considerable “bucks”
My plans are for the “weekend warrior” category of builder. You don’t have to be an expert carpenter to build my unit. Just follow the instructions and you will be ready to raise a bumper crop of fresh herbs.