How to Build a Raised Garden Bed

Planning, Building, and Planting a Raised Garden Bed

December 21, 2018

Learn how to easily build your own raised garden bed!


Raised garden beds are fairly easy to construct, even easier to maintain, and offer myriad benefits for your garden (and you)! Here’s how to build a raised garden bed in your backyard, as well as some advice on using the right wood and soil.

Raised beds are an easy way to get into gardening! Whether you purchase a kit or build your own, there are many great reasons for using raised bed gardening.

What is a Raised Garden Bed?

A raised garden bed (or simply “raised bed”) is a large planting container that sits aboveground and is filled with soil and plants. It is a box with no bottom or top—a frame, really—that is placed in a sunny spot and filled with good-quality soil—to become a source of pride and pleasure, and a centerpiece of the garden.

Why Should I Build a Raised Garden Bed?

Raised beds have many benefits. Here are a few reasons why you should consider using one:

  • Garden chores are made easier and more comfortable thanks to less bending and kneeling. Save your knees and back from the strain and pain of tending the garden!
  • Productivity of plants is improved due to better drainage and deeper rooting.
  • Raised beds are ideal for small spaces where a conventional row garden might be too wild and unwieldy. Raised beds help to keep things organized and in check.
  • Planting in a raised bed gives you full control over soil quality and content, which is especially important in areas where the existing soil is rocky, nutrient-poor, or riddled with weeds.
  • Raised beds allow for a longer growing season, since you can work the soil more quickly in the spring in frost-hardened regions, or convert the bed into a cold frame in the fall.
  • Fewer weeds are seen in raised beds thanks to the bed being elevated away from surrounding weeds and being filled with disease- and weed-free soil.
  • Raised beds allow for easier square-foot gardening and companion planting.

Learn more about the benefits of raised garden beds


Choosing the Right Wood for Raised Beds

Many people are concerned about the safety of their wood frame. First, rest assured that CCA pressure-treated wood is banned, as it was known to leach arsenic. To ensure that the wood lasts, there are several options:

  • Regular pressure-treated lumber sold today has a mixture of chemicals applied to prevent the moist soil and weather from rotting it. Although pressure-treated wood is certified as safe for organic growing, some people have reservations about using it, and there are various eco-friendly alternatives. 
  • More expensive woods, such as cedar, contain natural oils which prevent rotting and make them much more durable. They are more expensive to buy, but they will last many more years.
  • Choosing thicker boards can make the wood last longer. For example, 2-inch-thick locally sourced larch should last 10 years, even without treatment.
  • Avoid using railroad ties, as they may be treated with creosote, which is toxic.

Alternatives to wood include concrete blocks or bricks. However, keep in mind that concrete will increase the soil pH over time, and you will have to amend the soil accordingly to grow your best garden.

How Big Should Your Raised Bed Be?

  • First, you need a location that has level ground and gets the right amount of sunlight (6 to 8 hours per day). This should narrow down your options a bit.
  • In terms of bed size, 4 feet is a common width. Lumber is often cut in 4-foot increments, and you also want to be able to access the garden without stepping into the bed. Making the bed too wide will make it difficult to reach the middle, which makes weeding and harvesting a pain.
  • Length isn’t as important. Typical plots are often 4 feet wide by 8 feet long or 4 feet wide by 12 feet long. Make your bed as long as you like or build multiple raised beds for different crops.
  • The depth of the bed can vary, but 6 inches of soil should be the minimum. Most garden plants need at least 6 to 12 inches for their roots, so 12 inches is ideal.

Preparing the Site for a Raised Bed

  • Before you establish the bed, break up and loosen the soil underneath with a garden fork so that it’s not compacted. Go about 6 to 8 inches deep. For improved rooting, some gardeners like to remove the top layer (about a spade’s depth), dig down another layer, and then return the top layer and mix the soil layers together.
  • If you’re planning to put your raised bed in a space currently occupied by a lawn, lay down a sheet of cardboard, a tarp, or a piece of landscaping fabric to kill off the grass first. After about six weeks (or less, depending on the weather), the grass should be dead and will be much easier to remove.

Building a Raised Garden Bed

  • To support timber beds, place wooden stakes at every corner (and every few feet for longer beds). Place on the inside of the bed so that the stakes are less visible.
  • Drive the stakes about 60% (2 feet) into the ground and leave the rest of the stakes exposed aboveground.
  • Ensure that the stakes are level so that they’re in the ground at the same height, or you’ll have uneven beds.
  • Set the lowest boards a couple inches below ground level. Check that they are level.
  • Use galvanized nails (or screws) to fix the boards to the stakes.
  • Add any additional rows of boards, fixing them to the stakes, too.

Check out our video on how to build raised beds for your vegetables:

Soil for Raised Garden Beds

The soil blend that you put into your raised bed is its most important ingredient. More gardens fail or falter due to poor soil than almost anything else. 

  • Fill the beds with a mix of topsoil, compost, and other organic material, such as manure, to give your plants a nutrient-rich environment (see recipes below). Learn more about soil amendments and preparing soil for planting.
  • Note that the soil in a raised bed will dry out more quickly. During the spring and fall, this is fine, but during the summer, add straw, mulch, or hay on top of the soil to help it retain moisture.
  • Frequent watering will be critical with raised beds, especially in the early stages of plant growth. Otherwise, raised beds need little maintenance.

Raised Bed Soil Recipe

For a 4x8-foot raised bed:

  • 4 bags (2 cubic feet each) topsoil (Note: Avoid using topsoil from your yard, as it may contain weeds and pests.)
  • 2 pails (3 cubic feet each) peat moss
  • 2 bags (2–3 cubic feet each) compost or composted cow manure
  • 2-inch layer of shredded leaves or grass clippings (grass clippings should be herbicide- and fertilizer-free)

Makes enough for a depth of about 9 inches.

Raised garden bed. Photo by Oregon State University/Wikimedia Commons.
Square-foot gardening in a raised bed. Photo by Oregon State University/Wikimedia Commons.

Planning a Raised Bed Garden

To plan out the perfect garden for your space, try the Almanac Garden Planner! In minutes, you can create a garden plan right on your computer.

The Garden Planner has a “Raised Garden Bed” feature. It also has a specific square-foot gardening (SFG) feature, which involves dividing the bed into squares to make the organization of your garden a lot simpler (see photo above).

Which ever garden you select, the Garden Planner will show you the number of crops that fit in each space so you don’t waste seed or overcrowd. There’s even a companion planting tool so you plant crops that thrive together and avoid plants that inhibit each other.

Test out our Garden Planner with a free 7-day trial—plenty of time to plan your first garden! If you enjoy the Garden Planner, we hope you’ll subscribe. Otherwise, this is ample time to play around and give it a go!


Learn More

Have you ever thought about building your own raised garden bed? Or do you have one already? Tell us about it below!

Reader Comments

Leave a Comment

raised garden bed and cement ruble

I am new to gardening.We had some spare materials so we are making a raised garden bed out of sheet iron/old color bond roofing. Now we are in the process of filling it.We put cement chunks on the bottom at a height of around 8inches.The sides of the bed are 20inches in height.
My question is what do we fill the gaps with around the cement pieces with?gravel? sand?or just keep filling to the top with good organic soil?
And when the bottom 8inches is filled do I ad paper or something? or just top it up with organic soil?
Thanks in advance.

raised bed materials

The Editors's picture

We are not familiar with color bond roofing; a search suggests its an Australian product, so g’day! It may work as your wall but being metal it may also heat up more than natural materials (wood, say) and so conduct heat to the soil adjacent to it. Not necessarily a bad thing; it might depend on how hot it gets…and because of heat dries out the soil. Why 8 inches of concrete? What is underneath the concrete, soil? A hard surface? Is the 8 inches of concrete instead of soil, so you can save on soil? As for filling around the concrete, do some homework on what you want to grow. Some plants need a good 12 inches of soil, minimum, but some experts recommend up to two feet of soil so plants can spread their roots. You don’t want roots up against the concrete.  The soil will pack in around the concrete; so would sand, but sand does not benefit the roots; it helps—or increases—drainage, and you don’t want water to pour out. You could spread a little newspaper over the concrete but it will not last long; it may be better to fill with good organic soil and save the paper (newspaper) for possible use as mulch. To a certain extent, this will be an experimental season for you. Let us know how it goes!


Waist high raised bed but with only a 12 inch depth

We are changing over from a straw bale garden to a wood raised garden. Has anyone seen any free designs for a raised bed that is about 3 foot high but only want the depth of the bed to be about 12-15 inches? My husband is concerned about the best method to stabilize the bed since it will not be supported "by the ground", but elevated. Any ideas? Thank you.

Old tires for raised bed garden

Has anyone tried stabilizing old large tires for a raised garden bed? Is the rubber safe for use when growing food? I want to build a raised bed that will save some wear&tear on my lower back. I also prefer finding new uses for products to help reduce our ever growing landfills. This would also be economical for me. Thank you.

Old Tire Raised Bed

Hi Cynthia,

In the short term, yes you can make a planter out of old tires. However, over time the tires will degrade and release toxic carcinogens into the soil. If you want to use the planter for more than a year, it’d be a better use of your time to use a material other than tires. 

soil in an elevated bed

I plan to make elevated beds for my vegetables and wanted to know if my choice of soil mix is suitable. Equal parts if Composted manure, shredded peat, and vermiculite. I also have earthworms I want to add.

Soil Mix

Hi Dedria,

The soil mix you describe is essentially a potting soil mix, which has excellent drainage. The peat will make the soil slightly acidic, so keep that in mind when deciding what to plant. Also, depending on where you live, consider the climate; your climate may be dry and hot, wet and humid, or anything in between. Your mix is good for wet regions, draining well and not retaining too much moisture. If you live in a dry region, you’ll want some topsoil or a higher ratio of compost to peat and vermiculite to retain more moisture. Lastly, it is a good idea to get a mixture of different kinds of compost for a mix like this, as compost from one source will be lacking certain nutrients. We hope this helps!

Raised beds

Are boards of Juniper suitable for raised beds?

First time gardener

I built four 4x8 untreated pine raised garden beds. They are about 12 inches deep. I added hardware cloth and cardboard on the bottom of the beds to prevent critters and weeds. I am concerned that they are not deep enough for all kinds of vegetables to grow. Any tips/advice?

Raised gardens soil depth

Six inches is a minimum. Plants need at least a 6- to 12-inch rooting zone, so 12 inches is ideal. All the best with your garden harvest!

First Time for Raised Bed

My hubby and I have decided to give the raised bed a try in our garden this year; he'll be 75 in 1 month and I turned 71 just 2 months ago. Thanks for the great info on building raised beds, it came at the perfect time for us. We always raise 2 large gardens (about 1/2 acre total) of berries and vegetables so we do a lot of canning and freezing; we want to try our hand at home freeze-drying some of the fruits and vegetables this year. Hope the raised bed will make the gardening chores - weeding & harvesting - much easier on our old backs this yr. All our watering is done with the black soaker hoses - similar to a drip-system - and I'm sure that will work great for raised beds. Thanks again for the great info.

making those beds . . .

Thanks for the kind words, Thelma! Here’s hoping that you and your husband have a delicious and hefty harvest!

Small raised beds find space in sloped yard

My yard is on the side of a hill, with some very tiny areas that are only "sort of" flat. Small raised beds placed in the few level-ish areas have allowed me to have productive garden space without having to worry about my garden being washed down the hill during a heavy rain. In fact, I have managed to find appropriate places for six 4 foot by 4 foot raised beds. That is 96 square feet of garden space. My family, friends, and neighbors enjoy the vegetables from these small raised beds.

beds on slope

Good for you, Maria! We hope that other gardeners who read these comments take inspiration—and confidence—from your success. Thanks for sharing!

More advantages to raised beds.

In warm climates like we have here in southwest Florida nematodes can be a real problem. At this point there is no effective chemical control for these microscopic worms available to the residential gardener; however raised beds do offer the great advantage of easy solarization. During the off season when the beds are fallow, cover them with a heavy gauge, UV resistant plastic sheet and secure it well so that it doesn't blow away. The plastic should extend all of the way to the ground on the outside of the bed. This works very well in warm climates because the temperature inside of the bed can reach temperatures of up to 150 deg/F on a hot summer day. Temperatures that high will kill virtually every seed, insect egg, bacteria, mold spore, some viruses, and nematodes. Our fallow time here is in the summer, so this method is probably not too effective in colder climates when the summer is the height of growing season.

nematode nemesis!

Thanks for taking the time to share this great advice, Rononpi! You have clearly found a success method for defeating the problem of nematodes, and it’s highly likely that other gardeners will find this information helpful. We certainly did! All the best—

FL follow-up.

I am in South Florida as well. How deep are your beds... and What do you recommend putting below the soil to help with water retention?

Mixing bed soil with existing soil

Thank you for this informative page! We've had a garden in the ground the last three years and weeds& pests (rabbits, slugs, deer) have always been a problem. This year we're interested in trying raised beds to deal with both. I read here you recommend mixing clay- rich ground soil with the soil/mix put into the beds, but that will just perpetuate the weed problem I think. Any tips? We plan to put chicken wire on the bottom of the frames to keep out burrowing rabbits (happens with our regular garden fence) and the cardboard on top sounds like a good idea for weed suppression. But those two things are at odds with mixing soils too. Finally, any tips for pest fencing around the beds themselves that are easy to work with? Thank you!


The Editors's picture

Above we recommend

  • Fill the beds with a mix of topsoil, compost, and other organic material, such as manure, to give your plants a nutrient-rich environment.

Clay may be mentioned below re particular issues.

As for protecting your bed, it is entirely possible you may have to fence it in. Being raised does not eliminate pest problems; for materials, it’s your call re aesthetics and practicality, from chicken wire to cottage picket.

Or weeds. Weed and other seeds can blow in, birds drop them (or excrete them)—they can come from anywhere. To (almost) eliminate weeds, mulch.

Garden Too Shallow


Thank you for your informative article.

I bought some seedlings and I have planted them. However, I suspect my garden is too shallow.

How can I make it deeper without affecting the seedlings?


Deepening Your Raised Beds

The Editors's picture

Use a spade fork to very gently loosen the soil beneath your seedlings. You can temporarily remove them from the raised bed while you amend the soil depth. Lift the plants (keeping the roots in soil) and store them in trays, tubs, or buckets for the hour or so it takes you to work the bed. Replant as soon as possible and water well. Be sure not to bury the stems too deep when replanting. Keep the disruption of stems and roots to a minimum.

Raised Bed

I am building a raised vegetable bed on concrete. Is it best to line the bottom and sides with a liner. Or leave out the liner and add gravel on the concrete. Or use a liner then some gravel on top of liner to help drainage. Look forward to hearing from you with any advice.

Concrete raised bed lining

Hi Lesley,

A good way to go would be to use gravel on the bottom, then line it with landscape cloth.

lining with landscape cloth

Why add the landscape cloth? Is it necessary?

Landscape fabric

Landscape fabric is not required. Some gardeners use the cloth as an easy way to suppress weeds.  Fabric allows for the movement of air and water, unlike plastic. However, other gardeners do not like to use landscape fabric because it requires heavy mulching to cover the fabric and it breaks down over time.

Another solution is simply to layer 4 ot 6 inches of organic mulch such a bark or wood chips. This layer of mulch will prevent weeds by blocking light from getting to the soil. It also helps retain soil moisture.

Hi, I am purchasing a 1/2

Hi, I am purchasing a 1/2 acre that I want to put up a 8 ×12 greenhouse along with an 20 × 40 garden. I need help and suggestions for this project. Thank you for your help. Bev

Treated wood for raised beds

I have new raised beds brushed with Thompsons water seal.I'm trying to find out if this wood is now safe for using it for vegetables boxes.

We’ve never used this product

We’ve never used this product as don’t seal our wood; I’d call Thompsons.  That said, if it’s already brushed on, it should certainly extend the life of your wood. Just in case there is any leaching of its chemicals, perhaps avoid planting root crops right up next to it in the first year. Again, it’s best to call the manufacturer.

Raised beds

I am building raised beds, now I have been told to put down black plastic and build the beds over that to keep weeds down and help retain moisture, but with that said, has anyone done it that way? I have also been told if I do that, to poke holes in the plastic to help it drain? Recommendations?

bed cover

Here’s a link to a recent video we made explaining the ground cover:

If you use plastic, you should poke holes in it, otherwise you will have water collecting, eventually drowining your plants. Remember, the holes will invite weeds in…

The video uses a weed cover. This has inherent problems because some weeds will grow through it eventually.

Another alternative to both plastic and weed cover is sheet cardboard (boxes broken down and flattened). Or several layers of newspaper. Both of those impede weeds and and slow water run off/dissipation into the soil, and they eventually break down.

That’s all about retaining moisture and suppressing weeds under the garden.

On top, use mulch to retain moisture and suppress weeds.