Building Raised Beds from Concrete Block vs. Wood-Detailed Cost Comparison, Plus Other Pros and Cons

This year we switched from using wood for our raised beds, to using concrete blocks. In this video I walk through the detailed cost breakdown (based on current prices) plus the other advantages and disadvantages that we considered as we made the choice.

[@MichaelMiller-bi7by]

You are absolutely right. My five year old wood beds are rotting. I tell people its a modified hugleculter plan. When they no longer holding up the soil I'm thinking about just using contractor twine to mark the beds. If I had to do it all over again, it would be concrete blocks. As always, thank you for sharing and God bless.

[@WellGroundedGardens]

Good to hear from you! And same; I think the realistic life span on wood beds is five years, tops, and that’s without constantly changing the design (which we all know I’ll do 😂). At least you’ve got hügelkultur!

[@MyFiddlePlayer]

My 10-year old beds made of pressure treated lumber are starting to rot out, have already replaced several boards. I decided to replace them with metal beds because they were cheap and supposedly durable. Instant regret. I have not even finished installing them and they are already rusting and bowing. I'm thinking of replacing them next year despite the waste in effort and money, I'm just not sure if I should use lumber again or switch to concrete.

[@tiffanylarouech4065]

I used an old wooden bed frame as my raised bed. Stripped all of the backing and other material off, and it works great!

[@WellGroundedGardens]

Awesome idea!

[@beebob1279]

A beekeeping friend of mine (deceased now) used blocks like yours for her garden beds. She would use the holes in the blocks to grow root vegetables (usually red beats). Might as well use all the space she could. We are all in deer country and this was always an issue. She had a fence up to keep them out. She also had a water source up the hill from her. She used the slope of the hill to power her watering system. Worked great

[@WellGroundedGardens]

My plan is to use the block holes for some low-growing perennial pollinator plants, in the long term. I wish I had a slope to enable a gravity-fed system. We’re super flat-an elevated rain barrel is the best I’ll get. 😕

[@butette]

When I use concrete blocks, I also plan small vegetables like lettuce, baby bok choy, for example in the little square hole of the blocks to gain extra planting area.

[@WellGroundedGardens]

I was going to use mine for pollinator plants like alyssum, but am worried about the freezing soil breaking the blocks. Does yours just push out the tops and bottoms? Or has it caused any issues with the blocks cracking?

[@butette]

I am in zone 9a in Texas so I don't have any issue with freezing soil breaking the blocks and so far the crazy heat this past summer has not caused any issue either.

[@leighb.8508]

Brilliant comparison with pros and cons. Thanks so very much!

[@WellGroundedGardens]

Thanks! I’m so glad that it was useful. :)

[@trumpetingangel]

As the wood chips in your path decompose, they will share earthworms and decomposed organic material (via the earthworms) with your garden soil. Bonus! If you can continue to get more from time to time, you won't have to spend money on more blocks. Dozens of good ideas! Thanks!

[@WellGroundedGardens]

I discovered that our Township gives away free wood chips if we come and load them ourselves, so I should have a stead supply. It’s truly crazy how fast they break down 😳

[@jcombs2266]

Sage advice!!! Great video! Thanks.

[@WellGroundedGardens]

Glad you liked it!

[@cory9884]

So i watched this looking for ideas to apply to my garden. I started with cinderblocks i had lying around but ran out and ended up improvising with firewood. I took the top 8 inches of dirt out of my walkways and threw it left and right to make double digging more ergonomic, then once it was all fuffed up before the final shaping and leveling i stacked 16 inch logs and split firewood in the walkways to contain the dirt. It was basically completly free and you can bore holes in the logs to set up your hoops. Im hoping they will help hold and slow release water and eventually when they rot they will make great dirt. Just wanted to share.

[@WellGroundedGardens]

Nice! Do you have any photos?

[@kraziecatclady]

I did the flowerbeds against my house with 4x8x8 cinder blocks. It looks ok, but its not a raised bed. I dug them in and used paving leveler with sand to set them so that they won't shift. It was a great idea at first, but way more work than I expected. I also built a huge burn pit out of cinder blocks but toward the end of setting the bricks, I realized they don't line up right. I haven't touched that project in weeks now. I'm probably just going to use 3"×4"×8' garden wood for the rest of my beds.

[@WellGroundedGardens]

They are a TON of work.

[@bagsmode]

Wife and I have recently started to do this as well. Currently just one, however we did ours two levels high since we have a ton of roots and very acidic soil. Did the classic branches and compose layers, then some well seasoned mushroom compost. This first one, interestingly, got overrun with cucumber volunteers :D

[@WellGroundedGardens]

I have a cucumber volunteer in my garden, right now, after agreeing to my husband’s request not to grow any 😂. I suspect I’ll also add layers over time, but for now the 8” depth gets the job done.

[@franksinatra1070]

That's a good alternative to consider. One other consideration if you are working in a tighter garden space is the extra width the blocks take versus a sheet of wood. I expanded my garden the last couple years outside my fence and used logs that we have an abundance of behind our yard from old trees that have come down and that was a great free alternative for me but using them inside my garden to replace my boxes would either reduce the width of my bed or my walkways in between which would not be good. Your videos are good. I just subscribed and looking forward to more.

[@WellGroundedGardens]

Thanks! Good callout on the extra space. We plan to use the blocks to house our pollinator plants so they do double duty, but it’s a definite consideration for total space.

[@kathleens6837]

I started with a wood construction for a raised bed and quickly moved to the cement block. I have relocated and am in the process of building new raised beds with cement block now. I have plenty of wood debris to use for fill.

[@WellGroundedGardens]

Similar journey!

[@charleselertii6187]

Thank You! I have been contemplating raised beds with wood vs. concrete blocks. I am further convinced that concrete blocks are the way to go for me. Chuck in Florida. Thinking sbout 2 blocks tall for me.

[@WellGroundedGardens]

I was debating two layers and my back made the decision for me 😂. The nice thing is that it’s easy to add more, later.

[@anneg8319]

Such a logical decision. Wish I could change mine to blocks...

[@WellGroundedGardens]

We’re happy with them but MAN it was a lot of physical labor!

[@jantatangelo8596]

Loved your video! So many great ideas! We're putting together our 1st raised beds with 2-high concrete blocks which will last the rest of our lives!! Hard work by my Hubby & Granddaughter! Love the trellises for squashes and wire ideas to block gophers etc. Planning on Hügelkultur fill for the 1st time too. I've read that the block holds heat that increases the heat of the soil - how does that effect the plants? Thanks again for the great channel.

[@WellGroundedGardens]

Thanks! I’m impressed that you’re going with two layers of brick! That was my plan but I gave up after one…maybe next year. :) I do think the blocks help with thermal mass; we had plants survive much better than expected in our cold snaps last fall.

[@GEScott71]

Thank you for this, we are going to do it! For some reason we never thought of using concrete blocks, and I've resisted building the raised beds my wife wants because I know the wood will rot in a few years and can't be easily reconfigured. Oh and I'm dying to know what zoning rules control where you can plant your potatoes...?

[@WellGroundedGardens]

I’m glad that I’ve helped your wife’s case for raised beds! Lift with your knees and stretch. :) Our zoning rules are kind of nuts; we couldn’t put anything in front of the front plane of our house, even the 4’ fence around the garden. We built the house towards the back of the lot for sound reasons (busy road) and in doing so, we accidentally made the majority of it unbuildable. I’d planned a small garden towards the front of the property but without a fence around it, all I’d be doing is feeding deer.

[@zmavrick]

I have a bed that I made 8 years ago and filled the blocks with soil for stability. I live in Iowa with -10 F winters and have had no blocks break. However freezing does seem to make them more brittle and in another application where I was using them to hold down plastic and moving them daily they shattered while frozen and unfilled.

[@WellGroundedGardens]

Thanks-I’m hoping that mine will survive a good while if I only tap them back into place occasionally with a rubber mallet (when not frozen!), but I’ll see if our luck is as good as yours

[@chefgiovanni]

Nice build and thanks for sharing? Where are you located? Your plants growing need attention.

[@WellGroundedGardens]

We are in southeast Michigan-zone 6A for perennials. Got down to 0F last week (-19F with windchill…) 🥶

[@nicholasbenedetto6319]

Had wooden 4x4s, they usually lasted 4 years. Switched to cinder blocks, which last forever. And they stack without mortar. Used for vegetable garden and flower beds. Also used them to construct compost bins. Yes, it's a little more involved (strenuous) but well worth the effort. And you can do it in stages. Was surprised you didn't make the corners sharp. But, you probably weren't interested in going higher.

[@WellGroundedGardens]

In future years I may go higher but for now I’ve run out of motivation 🤷‍♀️

[@MissSandraK]

I’ve made 3 beds stacked 3 high, but it only benefited the deer this year😢

[@nicholasbenedetto6319]

@@MissSandraK when you have trouble bending, you'll see. Me, I had squirrels, raccoons, skunks. Coyote urine worked at discouraging them.

[@tiffanikeyes4269]

Love your channel. Do the beds not need to be deeper? I’m not new to gardening, but wanting to try raised beds.

[@WellGroundedGardens]

Honestly we started with one level because we could NOT handle the idea of any more brick laying. I plan/hope to take just one bed each year and add a second layer of brick because I would like them to be a bit higher for less bending on my part. They’re open on the bottom so planting depth isn’t the issue, but once I hit my 40s, ergonomics really started to matter 😬

[@MyLove-uj8zi]

My grandsons just built me a 10x3.5 planter box 30 inches high. We have gopher issues. I have back issues, this will help with both as I layered wire and cardboard then tree limbs under soil. I have to put steaks or rebar to stabilize block. Then add soil, but it will last my lifetime. I will slowly add more raised beds as time goes on.

[@WellGroundedGardens]

Good grandsons! We had groundhogs that I *think* are now gone, so we skipped putting down wire…I may regret that 😬

[@DIY.with.DianeD]

Have you considered laying the center row of blocks on their sides so 1- easier to walk on, and 2- won't get weeds growing up the middle where nothing is planted? Great job - no good project that lasts is done as fast or easy as other options!

[@WellGroundedGardens]

That’s a great suggestion!

[@lauraarsenyan3577]

I might have missed it, but could you explain how/why you decided to create a passage in the middle of the bed? And did you increase the width of the beds to compensate for the space?

[@WellGroundedGardens]

You didn’t miss it; I didn’t cover that in this video. Long story short, the best way to maximize my growing area given the dimensions I had to work with was to make ~8’ wide beds with a narrow (about 12” wide) permanent access path down the middle, covered in wood chips. That leaves a 3’-6”wide growing area on each side, on which I don’t walk. The approach lets me create wider beds but still access everything in the beds easily, even if I use trellises.

[@bonedigger666]

In my old area of garden the wood rotted and I used blocks. In the new area I'm using wood and will convert to blocks as I go along. But I only make my beds 4x8 or 4x10 so it's not that hard to replace over time.

[@WellGroundedGardens]

I also started with wood. So far I’m loving the blocks and was even thinking of adding a second layer…not sure my back is up for it, until maybe 2025. 😂

[@dougm2174]

Couldn’t you also have used a single column of cement block in the, in the center of each bed, butt turned 90° as a cost saver? You could still use the PVC in the same hole as the other side. If that makes sense?

[@WellGroundedGardens]

I thought about it, but am also using it as an access aisle, and 16” was as narrow as I could feasibly go. I wanted one standard design across all ten beds, so I didn’t ever have to fuss with them again.

[@misterdubity3073]

The other factor I think of is bumping ankles or shins against a hard concrete block edge or corner (or in the case of wood, any metal fasteners on the outside; or splinters). Cost wise: the wood bed lifetime of ?5 years vs block of ?decades?

[@WellGroundedGardens]

We’ve buried our beds pretty deep in wood chips in the aisles, but good point as it’s still possible to bump something. I think I’d add the width for sitting, too-not a major factor, but the concrete blocks do give a nice area to sit. I didn’t get a consistent answer when I researched their specific longevity; freeze/thaw will affect both materials so the absolute answer seems dependent on climate. On a relative basis, though, concrete should be MUCH more durable.

[@nicholasbenedetto6319]

Live in Chicago hot summers COLD winters. Not a problem if on a solid foundation. Each block is 36 lbs. They have 2" thick blocks you can use as capstones. Had a bed 4 high, 32", no problem.

[@WellGroundedGardens]

Nice! I’d like to make them taller over time but I need a year off after building this version, before my ambition will return. 😂

[@Raycheetah]

Very nice! Any thoughts on chemicals (lime, in particular) leaching out of the cinderblocks, and how to mitigate that? I'm just trying to plan ahead before I get started. =^[.]^=

[@WellGroundedGardens]

There’s a theoretical chance of it altering soil pH but I haven’t been able to find any scientific studies showing that it actually happens. When I check University Extension services (my go-to source) the ones with content on it all note the hypothetical possibility but still recommend them over other options. It was good enough for me. :) If I had acid rain issues I’d be more concerned about that interaction. I WILL flag that I wouldn’t use blocks made with fly ash, but that’s a separate risk related to trace chemicals.

[@Raycheetah]

@@WellGroundedGardens Thank you for the prompt reply. =^[.]^=

[@WellGroundedGardens]

@Raycheetah sure thing!

[@deborahmaier4272]

I disagree with using for beginning gardening. When I started my garden I looked for different materials to build. I knew I was going to start out small and eventually increase the size of, so I wanted something that was flexible. I took cement blocks and leave them right on the grass I put cardboard on top of that and leaves the fall before. Over the years I've added more blocks until the size garden that I.

[@WellGroundedGardens]

I’m glad that it worked for you! When we started out, I found the idea of building large beds very daunting. If I’d known how addicting gardening can be, it would’ve been a different story. :)

[@user-ky4hc1bx7s]

it's $23 for one 10ft board of cedar. Wood is like 20x more expensive than the concrete block version.

[@WellGroundedGardens]

Yeah there’s no way we could afford cedar. When I’ve used wood in the past we would go with pine, and accept that it would need replacing…the CMU was a pain to install but has way better longevity.

[@dac7046]

Why people would do either is beyond me assuming they don’t have an excess water problem. I finally ripped out the last of my hard sided raised beds and things have never been easier or better. Open top blocks are the worst!

[@WellGroundedGardens]

We do have an excess water problem-especially in the spring. Clay soil + heavy snow melt off + wet, rainy springs

[@DesWorld910]

You shouldn’t use pressure treated lumber in beds that you are growing food in as it leaches chemicals into your food supply. Untreated hemlock or cedar is the best option but more expensive.

[@WellGroundedGardens]

In theory it can; that’s one of the reasons why I like to use the CMU blocks

[@butette]

Seriously, how many people are you planning to feed with that much planting space?

[@WellGroundedGardens]

Four 😂. I grow a lot for root cellaring and canning-potatoes, sweet potatoes, onions, tomatoes, etc. I only need around 1/3 this much for the fresh things like salad greens

[@butette]

That is a nice big garden for planting. Hopefully, you have help to maintain it! I like the wood chip walkway between the beds.

[@bootangy]

woood is sooo expensive

[@WellGroundedGardens]

Especially lately!

[@robertbutler8004]

How my godfather those blocks are disgusting.

[@WellGroundedGardens]

How my godfather?