How to put your yard to use with raised garden beds:

Choose a location in your yard that gets maximum sun exposure – all day long, in all seasons, if feasible. Yes, even if that means right in the middle of the front lawn, because… why not?! Most vegetables prefer to get as much sun as possible, with a few exceptions.

If you have a small space or obstacles to work around, creating a few garden areas that end up with partial shade is okay. We have a handful of beds that get far less sun than the others, shaded by our house or neighboring trees. We can still utilize them to plant veggies that are more shade-tolerant like lettuce, kale, asian greens, spinach, arugula, or mustard greens, to name a few. If you live in a climate with extremely hot summers, your garden may even thank you for a little late afternoon shade!

Is your only garden space on a hard surface, like a concrete patio? You’re in luck! I wrote an article dedicated to building and installing raised beds on top of hard surfaces – either right on the ground, elevated, or even some that are mobile. We just added raised garden bed to our asphalt driveway. The design is essentially the same as what you’ll find in this article here, but with a few modifications/options for the bottom. Plus, extra tips about drainage considerations. Check out that article here.

Changing Seasons and Shadows

Don’t forget that the sun’s path changes throughout the seasons! In the winter, the sun dips lower in the sky – on the southern horizon if you’re in the northern hemisphere like us. That is particularly important to pay attention to if you live in a place with mild winters and hope to garden year-round.

I can’t tell you how many times I have seen people place garden beds along a fence, wall, or house, and I have to cringe a little. It makes sense aesthetically, keeping the garden tucked up against something, “out of the way”. Whenever possible, I suggest to keep raised garden beds out in the open, away from structures. Because unless that wall or fence is facing south, it is going to cast shade on your garden. That is not ideal.

“South-Facing” Gardens

If you’re in the northern hemisphere, a south-facing garden is an ideal choice. This orientation will provide your garden maximum sun exposure from the south in all seasons. As an exception to what I mentioned above, placing a raised garden bed along a south-facing fence or wall does work well. The only time that orientation will create shade is in the very latest hours of long summer days.

If you live in the southern hemisphere the logic is just the opposite. There, a north-facing garden would be best.

One of the many, many beautiful things about gardening is that it can be totally unique and individual! Whether you have a small yard or acres of open space, beds can be designed to fit that space. Within your limits, let your imagination run wild on the layout, number, shapes, and sizes of beds! On the other hand, there are definitely some sizing and layout best practices to consider during all that dreaming. Let’s discuss.

Layout

In addition to considering sun exposure, you want to think about working in and around your beds. Preferably, with comfort and ease!  Are there already other structures, plants, or features in your space that you need to work around? Do you plan to have multiple beds?

I have seen some very tightly spaced beds, like some spaced within one foot of another. While this can be excellent for maximizing yield in a small space, I also can’t help wonder… Isn’t that a pain in the butt? In our garden, we prefer at least 2 feet between beds, minimum. Most are 28 to 32” apart. That distance creates the perfect spacing to move a wheelbarrow or our favorite garden cart up and down the aisles between the beds. It is not only handy, but essential, for our backs sake.

Additionally, a garden bed in the hayday of summer can be overflowing with plants! They’ll come over the sides and encroach in your aisle space.

Test it Out Before Building

Before making any final decisions, grab some scrap wood, rope, broom sticks, or whatever else you can find! Lay it out on the ground in the approximate space and size you’re imagining.  This will give you a better idea of what the space would actually look and feel like once it’s all in place.

To determine your lumber needs to build a raised garden bed, you’ll need to choose the type of wood you want to use, and calculate how much will be needed for the project.

Wood Choices for Raised Garden Beds

What kind of wood should I use for my garden bed? It depends on your personal preferences, budget, and what is available in your area. An ideal wood choice will be long-lasting, sustainable, and safe! Let’s review a few great options, as well as a few not-so-good options that should be avoided.

Redwood and Cedar are the most popular, high-quality hardwood options for building raised beds. Neither need to be stained or sealed in any way. They are naturally very durable on their own!

For any wood selection, look for ones marked with “FSC” – which stands for the Forest Stewardship Council. FSC certification ensures that products come from responsibly managed forests that provide environmental, social and economic benefits. Also look out for bowed or cracked boards! Keep those out of your pile.

AVOID using these materials for raised garden beds!

• Treated lumber, or pressure treated lumber – Historically, an arsenic-based compound called Chromated copper arsenate (CCA) was used for pressure treated lumber. CCA was banned in 2003, and was replaced with various “less harmful” chemicals to treat wood. These include Alkaline copper quaternary, Copper azole, copper-HDO, and copper naphthenate.  While these are all reported to be less toxic than arsenic, I personally still would not use them. Upon reading an article from Iowa State University, it explained studies have found that these chemicals do and will leach into the surrounding soil they’re in contact with. Our Home Depot is legally forbidden to cut pressure treated wood for you, though they will cut all other untreated lumber. That is saying something.

• Railroad ties – These are treated with Creosote, deemed a “probable” human carcinogen by the EPA. It is also known to damage plants that are growing near it.

• Recycled or reclaimed wood that you are unsure of the origins, age, or if it has been treated, stained, or painted. They could be toxic!

Alternative materials for creating raised garden beds:

Here I am, assuming that you want to create a wooden raised bed… However, there are other options aside from wood. Alternative materials that could be used to create raised garden beds include: concrete blocks, bricks, cinder blocks, felled logs, galvanized metal tubs, wine barrels, straw bales, or poured concrete, to name a few.

Each of these have their pros and cons. You’ll need to do your research to ensure the material you are using is safe, effective, and will work for your situation.  For example, if you choose cinder blocks or concrete, check to ensure that it does not contain fly ash. Fly ash is a concrete additive that contains heavy metals, which is not something you want leaching in your soil! Additionally, if you live in a hot climate, some of these materials (like galvanized metal or concrete blocks) may heat your soil to an undesirably high temperature.

How much lumber do I need to build a garden bed?

Once you know your desired bed size(s) and wood type, you can run some calculations! Drawing a sketch of your bed is very helpful in the process. It makes it much easier to visualize and add up the total lengths of boards needed. Note that you do not need one board for every piece of each side! You can often use one board to create many pieces of your puzzle. Let me explain.

This step is easiest if you already have your wood picked out and know where you are going to buy it. That way, you can see what size of boards they sell. The heart redwood 2×6 boards we use are most commonly sold in 8 or 12 foot lengths. So for example, let’s pretend we are going to build a 6×4 foot bed. We would want to buy the 12-foot boards – because those could be cut in half to create two perfectly-sized 6-foot pieces for the long sides of the bed.

Corner Supports

For this design, you’ll also need a durable 4×4” board for the corner supports. We use redwood for these too, though heart wood is not usually available. Definitely choose a hardwood like redwood or cedar here, even if you are using a softer wood for your side boards. A softer wood would not make the best support pieces. These are what hold your bed together! You want them to last. For an 18” deep bed, one 6 foot board can be cut 4 ways to create corners. If you’re doing a deep 24” raised bed, grab an 8 foot board.

Other lumber size considerations:

In regards to thickness, most wood will come in two options: 1-inch thick, or 2-inch thick. Keep in mind that boards labelled as 1-inch are really only 3/4”,  and 2-inch boards are only truly 1.5 inches. If you choose to build shallower beds that won’t be subjected to as much soil and pressure, you could choose 1-inch thick boards, which may help keep costs down. However, thicker boards will most definitely last longer. They’re also the most sturdy choice for deep beds.

One last consideration when choosing lumber is: do you want to use 2x4s or 2×6 board? We prefer using 2×6. Fewer of them are needed to reach the desired height of the bed! Or maybe you’ll even be able to locate 12” wide boards, though we don’t see those much.