thinking about installing concrete raised bed measuring 3 feet by 3 feet and 2 feet tall, with bottom open to the native soil. is there any down side to this for vegetables?

No room for a significant amount of vegetables.

ZM

For a bed that small I think wood would be a lot less trouble than concrete. Just don't use treated wood. If you have room to make it bigger you could grow more. if your soil under it is pretty good I don't think you need 2 feet tall.

While you are getting responses about size here I think you are asking about the construction material used. I know people grow veggies in beds made of cinder/concrete blocks so I assume that would be ok.

New concrete can leach limestone and calcium into surrounding soil and raise the pH higher than what many veggies prefer.

What vegetables?

Seems like not the best design.

RpR said: What vegetables?

Asking me or OP? — common favorites like tomatoes and squash are reputed to prefer (not necessarily require) acidic conditions, <6.8 pH. Soil around new concrete installations is known to lean alkaline.
https://rivertonconcrete.com.a...

Generally speaking most of our eastern soils tend toward the acidic, and the concrete might even make the veggies do better... unless you have a limestone ridge or something nearby, already causing higher ph...

I'm with the people that feel like a larger garden bed would be worth considering...

3x3 sounds really close to pot culture...

I tried searching "soil ph charlotte nc"

https://content.ces.ncsu.edu/s...
Nearly all North Carolina soils are naturally acidic and need lime, which neutralizes the acidity, for optimum growth of crops, forages, turf, trees, and many ornamentals.

The big box stores carry ph meters for home testing soil ph if you are unsure.
https://www.gearhungry.com/bes...

I'm trying to keep my curiosity within the original question, but would really like to know if another material or bed size is up for consideration. It seems like such a big, expensive, and permanent fixture, I want you to be sure that's what you want.

thanks everyone! the idea is for when I am in a walker or wheelchair and need to reach plants when sitting. thinking of anywhere from 12 to 36 of the 3 by 3 by 2 feet tall beds. need beds that do not move or be blown around by winds. basically want to grow everything from salad greens, potatoes, to zucchini!

I like the idea of the tall raised beds myself, for the reasons that you stated, but would be inclined to consider something like these metal modular beds rather than something made of concrete:
https://vegogarden.com/product...

I agree with other replies about the 3x3' size, especially with the concrete wall those are going to waste quite a bit of space. Raised beds that are 2 or 3 feet wide but longer would be easy to reach across and provide plenty of room for growing most garden plants.

Shake head, 4' is too wide, honestly. Moles are a problem whatever you use as sides, place metal fabric under the bed. Other problem can be summer sun overheating that west side. Am currently (slowly) restuffing my raised beds. Solid sides do help keep the fire ants from building towers inside hollow walls. My best pepper 'pot' is a small horse trough - BUT I have a large bale of peat against that west side and the pepper does great. Leave yourself at least 44" between the beds. Raised beds are apt to use more water than other types of beds so the open bottom is necessary-especially when we get those gully washers for rains. The extra water also discourages the fire ants, but the downside is that there will always be roots. The dirt inside will sink every year as well - scientific fact that it is NOT possible to refill a hole with the dirt you removed, ain't gonna happen. I did line the bottom of mine with (metal fabric and) landscape fabric, and I noticed it is still there, but the sides sink with the dirt. Any cardboard layers will turn to dirt in a year. You can also stuff the bottom with pine branches for the bottom 10" if you have any, but pack them in - or use old decaying pine tree logs - still 10" if you are using the 24" sides. The cement won't affect the dirt, it just doesn't, but I painted the inside of my cinder bricks to stop the fly ash in them. (And raise cane with the frogs and fire ants inside them) picture from 2018 Spring when we used scrap to build them



I end up NEVER planting 2 plants side by side, just no room when grown.



These are from past years, this past summer was brutal here, my tomatoes are gone by July, cukes hang on a few weeks later. I will switch to cell phone for a current picture of my restuffing, It is being done to block that west wall and these logs against the west wall are 20", the others are 10"








Plants with short root systems- thyme, oregano, onions, corn, need to be closer to the ground than in a raised bed, but my thyme does grow up over the bed walls, vines with deeper roots do well at 2' or even 1' depths, cukes, tomatoes, squash. Remember, those fruits are going to be 2' higher from the ground than they were on the ground. I have a step ladder, but vines CAN grow along the ground.

these pics and messages are very much appreciated! yes, I am planning on 5 foot wide paths between each bed, and hopefully adding metal trellises in some of the rows for the vining plants. does metal rust or fall apart when it is inside concrete? I know it is a lot of space for the paths, and not much percentage for the actual soil, which is why posting these ideas for such experienced gardeners is so awesome! has anyone seen or heard of veg gardening spaces with concrete paths and concrete raised beds? thank you!

metal rusts where it enters the concrete and water drips down to it. proper concrete forms entirely cover metal. You really don't want permanently embedded trellises, and most folks use raised beds because they can be dis assembled and moved, I do have bricks the kids laid in my walkway, it is much easier to maneuver there, but in our climate, weeds always grow, and ants like being sheltered by the paths. Of course, I also find it easier to treat the bugs in the walkways without disturbing the dirt in the beds. I have cardboard laid in the paths to block weeds, easier to yank it out when the weeds grow on top. Most of my trellis are also deer blocks. I have seen permanent beds, but don't think I have ever seen concrete ones, have you considered a trial raised bed? I just get head shakes when I think about plants and permanence.

@beckygardener has made a Florida garden that addresses some of the issues in my Maryland garden, and I'm thinking about mooching some of her ideas relative to concrete vs wood, sloping ground, raused beds, etc. in my garden next year. And her garden is frugally made and beautiful to behold. Soooo - here are some links from her experience I've saved to get anyone started reading, should they be interested:

- 020913 beckygardener - quote https://garden.org/thread/repl... many great ideas "...fan of cinder blocks...concrete..."
-- line cinder block holes w/recycled nursery pot plastic to reduce heat effect; CB caps; place to sit/weeding; paint blue; liriope in holes
- 020913 beckygardener more concrete bench ideas - https://garden.org/thread/repl...
-- make bench top from purchased mold - (next post, RickCorey suggests concrete glue instead of mortar)
Her garden slopes, so more construction ideas relevant to that
--- https://garden.org/users/profi...

- rebuilding a garden on budget: The thread "Becky's Budget Garden" in Garden Photos forum Beckygardener - don't build w/wood.

Freezenatnc - thanks for bringing up this subject - and all comments here are much appreciated

Lots of good comments here. I can't really speak to raised beds. I'm just stuck on thinking that having concrete work done is the most expensive way to do it, and unnecessarily expensive. I understand the side benefits of gardening, but to grow vegetables to 'save money' is hard to do (impossible, in my opinion) if you spend a lot creating these beds. Anyone, please correct me if that's wrong for those who have raised beds.

If you have to do most of the work seated, how far can you reach for any length of time? Or can you stand for a bit, to pick from treliis and plants, and poke tools into the soil?

Who is going to make or pave whatever you need done? Will these beds add value to the property?

When we are doing the work ourselves... concrete isn't necessarily all that expensive to purchase by the sack, mix in wheelbarrow and scoop into wood forms...

although, concrete blocks or brick seem like they might make better sense.

I'd still want 4 foot wide beds rather than 3 foot...

5 foot wide paths sounds better than what I usually see... very important to have enough room for the garden cart / wheelbarrow / wheelchair...

3 foot long just seems too short... I'd want them way longer...

It is possible to create beds too long... I used to have beds that were like a hunert foot long... that was impractical...

10 or 15 foot long would probably be a decent length for one bed.

Do you have experience growing vegetables, or are you doing any gardening, now?

As I reread, I see you are not physically limited now, but looking to plan ahead. Good for you

Did we ask, are all the planned beds going in full sun? That's very important for most vegetables. It you have trees around a lawn, like me, those tree shadows can be surprising, esp in spring and fall.

I got mentioned on this thread by Karen.

I use concrete on just about everything outdoors if possible because it lasts. Nothing worse than having to do everything over again if it's wood and rots.

I've posted all kinds of different gardening ideas, but this article might suggest a way to make a concrete garden bed frame "narrower" instead of using cider block which does take up quite a bit of space. I've used pavers turned on their side. I use construction adhesive to hold them all together. I've had my concrete beds for quite a few years now. They've adhered together just fine since I first built them. My article about using pavers: https://garden.org/ideas/view/...

If you are worried about them leaching, you could try painting/sealing them. I've painted mine numerous times depending on what color I want any given year. To my knowledge, the largest paver size is "Oldcastle 23.3 in. x 23.3 in. x 1.8 in. Grey Concrete Step Stone". You can google that. They currently cost about $9.00 each.

If you need the garden bed taller, cinder block would be your safest bet if you choose concrete, but again you lose garden bed space due to the width of the cinder blocks.
One thing I will note.... I do not know how well concrete block/pavers holds up in freezing temps. I've heard they might crack. Not sure if that is true or not, because I live in Florida.

Good luck! I think making an easy to access garden bed at wheelchair level is a great idea!