River
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Height of raised beds

I can’t help but notice that most of the raised beds are only a height on the average of 11.5 inches. Especially on the kits. I don’t see a large advantage as far as bending down and I would want more height especially for tomato plants and etc. Perhaps around 24-30,inches

In my neck of the woods, Mobile AL we receive a lot of rain year round. Plus the humidity levels are high. So building out of wood would not last long. Even redwood will rot rather quickly in our area. Pressure treated wood would last even less time. My land slopes to some degree, so I would not be able to raise it off of the ground.

I think it is a great idea but the cost would be high with composite. I really don’t see Any other option. For the last 6-7 years I have used containers on my driveway. I can move those around.

Any suggestions how to build a rot free raised garden at a reasonable cost? My idea of reasonable would be no more than $200
Mobile al zone 8b

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Gary350
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Re: Height of raised beds

Lowe's and Home Depot both sell a composite wood that is basically foam plastic. It is not as rigid as wood, my friend built a deck the boards are wavy between the 16" center rafters. When we walk on his deck composite bows down when we step on it. I don't know how many years is last or the cost it should work for a raised bed. It is expensive I was looking at it 6 months ago it is 2 times more expensive that wood. Yesterday I went to buy 2 sheets of plywood it was $14 per sheet 3 months ago now it is $30 per sheet. I put my project on permanent hold. PT 5/4" deck boards are crazy expensive too. Prices for many things have doubled in 3 months.

Nyan
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Re: Height of raised beds

I live in northern Alabama and I have just about retired all the wood beds as they rot away.

All the beds are now made out of concrete blocks, for several reasons.

You can take them apart very easily if you want to change locations, etc. Good exercise! LOL!

If you are working with much slope, you can actually dig in the ground to make another row of blocks to keep it level down the slope.

They last forever! And if the bed becomes uneven you can fix the problem by moving and shimming (with dirt or wood) a few blocks to put it back even. You can also buy a seal/paint for them that will help hold them together and hold in moisture if needed. Some of the seal types make such a strong bond that you would have to break the blocks to get them apart!

You can fill the holes with dirt and plant things that can take dryness like onions, garlic or even gladiolas. Or, you can use the holes to put in poles for frames to hold tall plants and/or climbers.

I usually build the beds two blocks high for comfort (and deep soil) so you can drop a board on top and sit down to plant or weed. Very comfortable!

A 4 ft. by 10 ft. (inside dimensions) bed takes about 24 blocks per level, and you can expand as long as you want or as short as you need. At somewhere around $1.75 a block you can build a 2 block high bed for around $84.

Filling it is the costly proposition, so I usually bury tree trimmings or logs and cover with dirt and compost to save money. As the logs start to rot away, I just add more compost, dirt, or cheap bagged "dirt" (Walmart stuff) right on top of the usual mulch, which keeps it full and fertile. Mix everything up every few years just to keep some native soil in the root zone, or add some "real" dirt so you keep it healthy.

Okay, that's all I know about it... :()

Vanisle_BC
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Re: Height of raised beds

Nyan; one of my wooden raised beds is in serious need of replacement. Your concrete block method would be an option. I'm curious about your use of a sealer - is it for purely decorative reasons, or are you saying that otherwise the beds lose moisture through the blocks? And if the block cells are soil-filled I don't suppose they'd really need anything to hold them in place?

Thanks for sharing your experience,
VanIsle.
The terms of political discourse are not models of precision. - (Noam Chomsky)

River
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Re: Height of raised beds

Thanks for the replies. I thought about the concrete blocks. Not so sure my wife would think that looks okay. For practically it makes good sense.

Sort of reminds me when I used those in the early 70’s to build my first shelving for my stereo and turntable. Very functional
Mobile al zone 8b

PaulF
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Re: Height of raised beds

ImageThis is what we did. The old waterers had rusted out bottoms and were free. I put a foot of old oak logs at the bottom, covered with window screening to keep the foot layer of plain dirt followed by a foot of potting mix. Total cost for 2 seven foot diameter raised beds about $25. These are about three feet tall, not much bending over and the harvest has been much better than in-ground or close to the ground raised beds.
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River
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Re: Height of raised beds

Nylan did you use the blocks that are 4x4x16 (7.625x7.625x15.625)
Mobile al zone 8b

Nyan
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Re: Height of raised beds

I used the 8x8x16 foundation blocks because I started with those for the first one I made, and they worked well for me. They build up to nice height with just two rows, and it goes quickly when you don't have much time.

VanIsle, I haven't used any sealer on the blocks (well, I painted a bed one time, but now it's parts are in several beds) but they do let water wick away from the soil in summer. But it kind of balances out for us to have the that happen during our insanely wet spring and fall (the space between blocks help too).

I've tried wood chips in the holes and rocks in the holes, but soil works as well as anything as you can grow stuff in it, or punch a post down through it to run wire for green beans or other vines.

The blocks I use are about 30 pounds each, so there isn't any problem with them moving, especially when filled with soil.

One other thing I found about the block beds is you can cut a board (2x8 or 2x10) that will reach across the bed sideways, and screw a couple of small pieces of 2x4 under it to fit in the block holes. Then you can lean over the beds and support yourself with them, to rest your back. Just pick them up and move along as you go. Nice when working toward the middle of the bed!

Vanisle_BC
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Re: Height of raised beds

Nyan; thanks for the details of your concrete block beds. I too use the 'plank across' method on my wooden but rot-prone beds, for working on the middle without a lot of stooping. (Or just for a rest.)

I have one bed in immediate need of repair/replacement. Disadvantages for me, of the block structure, would be materials delivery cost (at least $100) and the physical strain of handling the blocks. I'm ancient, with a bad back 'etcetera'. As well, they would add 16" to the bed dimensions (subtracting it from the rest of the yard) and require extra soil for filling. Still, the idea has appeal. Then again cedar is plentiful around here; light to handle and lasts a bunch of years.

It's the wrong season for work on structure anyway - way too hot, and plants are in full growth, so .... Hmmm, we'll see .....
The terms of political discourse are not models of precision. - (Noam Chomsky)

River
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Re: Height of raised beds

The area I would have to build a raised garden bed with concrete blocks is sloped.
This would complicate the project. I would think that require a good bit of digging.
Mobile al zone 8b

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Gary350
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Re: Height of raised beds

River wrote:
Wed Jul 22, 2020 11:49 pm
The area I would have to build a raised garden bed with concrete blocks is sloped.
This would complicate the project. I would think that require a good bit of digging.
Sloped...... if others can do it, you probably can too.
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Vanisle_BC
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Re: Height of raised beds

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Gary350 wrote:
Thu Jul 23, 2020 1:39 am
Sloped...... if others can do it, you probably can too.


Wow, nice job Gary. Did you have much help?
The terms of political discourse are not models of precision. - (Noam Chomsky)

River
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Location: Mobile

Re: Height of raised beds

They had skills. Mine are limited
Mobile al zone 8b

River
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Posts: 109
Joined: Thu Aug 21, 2014 2:18 am
Location: Mobile

Re: Height of raised beds

Just for the record I did a google search and you tube search. I could only find info on using wood on sloped land.

I was entering how to build a raised garden bed using concrete blocks on sloped land.

Is there perhaps a better way to word that where I might find information?
Mobile al zone 8b

Vanisle_BC
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Re: Height of raised beds

River; I guess the conventional way to go would be excavating to make a level base, with the bottom blocks at the upper end of your slope partly or wholly buried (depending on the steepness of your land); or else if it's quite steep you could have a stepped base with more tiers of block at the bottom end of your slope than at the top .

Or I guess you could try just making the base at a constant slope with the blocks all leaning downhill lengthwise. That might work OK if the slope is gentle. But tying the end-walls in to the side walls could be tricky or impossible. You wouldn't want those 'leaning downhill', especially at the lower end of the box.

A lot will depend on what steepness you're talking about. By the way would you intend for the soil surface to also be sloped, or to be 'stepped'? And would it be preferable - or even possible - to place your bed across the slope rather than down it?
The terms of political discourse are not models of precision. - (Noam Chomsky)

River
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Location: Mobile

Re: Height of raised beds

The biggest issue would be causing erosion.

When I had a concrete driveway put in years back I was told I would need to be concerned due to the slope that soil could washout from underneath The driveway.

I would have thought that one side would cause a pocket or tunnel to develop and cause the washout from opposite side.

It does have washout just on one side after a large storm and it is not caused by the other side. You can see the runoff when it rains hard and if you know Mobile we can get 3 inches in 30 minutes. It literally runs off and washes it out from underneath. So I keep a large pile of soil to add it back and pack it back in.

I suppose you can see my skepticism
Mobile al zone 8b

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