How do raised beds stay in place without a border

I have seen raised beds all over town with no border around them. I'm wondering what makes the dirt and mulch stay in a bed that is very much raised? I was told that a trench needed to be built around the bed.

Can you post a picture? I'm assuming it's not really a raised bed but more like a berm, and with those unless the slope is really steep they would generally stay in place just fine. If there's a trench around it, it's probably there to keep a nice edge and keep the grass from growing into it (you'd have to do some periodic maintenance to keep the edge looking nice, otherwise the grass will have a tendency to creep its way into the bed).

I only plan on raising my beds about 6 to 8 inches. If I use landscape mix and pine straw as a mulch, will it stay in place.
I have found out that I have Caliche Clay (sp?). It's soil that they've added something to. It was used to build my house place up before the house was built. I have dug in it for years. Why I didn't raise the beds in the first place, I will never know.
I'm thinking it maybe to difficult to dig a trench in this mess. Do you think the beds will stay put or do you suggest a border? Borders can get expensive.

6-8 inches is not that much, you could even make a berm that's taller than that in the middle and probably be fine as long as you mulch. The trick is that a berm is sloped, so it's taller in the middle and slopes down gradually until at the edges it's the same height as the rest of the yard. It's not the same depth all the way through like a raised bed would be. If you want it the same depth all the way through rather than sloping, then you need to do a raised bed with some sort of containment (landscape timbers aren't typically that expensive and could work fine). If you go with the berm approach, you don't necessarily need a trench or a border--the main point of doing those would be to make the edge look clean and help keep grass from creeping into the bed. You can do that maintenance without a border, it just takes a little more work and the edge might not look quite as clean depending on how you do it. Same as any other garden bed--if you put in physical edging of some sort it keeps the edge looking really nice and crisp and you don't have to go through as often cutting back the grass to keep the edge looking clean.

Hi...

Let me say you can do this and get it complicated or you can do it simple....

Simple... Throw down what ever you want to raise the sides and hope they do not push over. If you use wood put down the wood, fill behind and walk away...LOL... Neither will last long. BTW Landscapping timbers will rot as any wood will, and will collect bugs.

So if you want a nice raised bed I have done, and seen the type where one uses wood, brick, stone or a manufactured type of "retaining wall". They are all nice. Some cost more then others, some will last longer and cause you less work then others. (I'm for not work after the job is done type of raised bed, so stone is great.)

If you use PT and it is a veg. garden you are raising, there may be seepage into the ground of the chemicals. I use untreated wood, but then I do a backfill of rock and raise the wood in a bed of rock to keep the wood's life a little longer.

Anyway when using wood, mostly I have seen where one takes a 2x4 or 2x6 or 2x8 or what have you, and nails or screws the ends together or to a support beam in the corners. The lumber is usually "heavy" enough to keep the dirt from pushing the wood out. If not one puts in another support bean as at the corners, in the middle and nails or screws.

These corner boards can be longer then the boards holding back the dirt, which are then driven into the ground.

The picture I made shows the corner board a bit above the other boards, but it can be level with the other boards, or even higher to perhaps support a solar light, or high enough to nail netting to or something to support vines etc..

When using stone, like blue stone, the stone needs to be large enough to hold back the dirt, the same with brick. In each case one needs to put in a stone or brick at the opposite run as the rest of the materials to steady the wall.

Hope this helps.

Nancy

Oh I also wanted to say... if I you want nothing at all and do the slope method, and you have clay, put an outside brim in clay, smooth it with water, slap it to make it smooth, then you can put straw behind or all around.

Clay is used in raised septic systems to hold back the "insides"...

Also at some point the plants themselves will hold the dirt and keep the sides from "falling in", it is the first few weeks that are a problem, but 6" should not be hard for you to maintain and keep the brim in place.

Happy planting.

Thanks so much. That helps me a whole lot.
Do you know my husband dug out 18" in one bed and put in landscape mix. This year plants looked stunted and bad. I decided to replace some plants, so I dug a hole about 24" and there was water in the bottom of it. After about 10 minutes, there was 4-6 inches of water in there.
What a complete mess and waste of time and money. I don't know why I didn't raise the bed to begin with.

Do you know if you are in a flood zone or near spamps, or a big lake?. The water is hi and plants that like water should do well for you, but hings that do not like wet roots will do better in a raised bed, however they will dry out faster.

In my opinion there is no need to dig out and remove dirt, rather put in and inprove what you have. We had really crapy junk dirt, more clay and bedrock type stuff. 9 years later, I can put my fingers in it to plant. We kept putting in leaves, wood chips, compost, horse stuff... and in the end we now can grow almost anything. We still have junk down below at the 16" mark but hell most veggies do not go that deep anyway.

I am not sure what landscape mix is, but I tend not to use commercial mixes. Another thing that may help is leaves of willow along with the rest of the compost you put in the ground. If you can find a willow tree that has recently lost its leaves, crumble them up small and put them in the ground too. You can also make willow bark tea and give it to your new plants it encourages roots..

Willow is used in rooting compounds, so the chemical in the willow helps the roots. Some may disagree, but I like to do this and it seems to help.

Nice sharing with you... and Good luck.

Nancy.

The beds right beside the front of the house and half way down the sides are raised. I have to fight with Crepe Myrtle roots there.
The other beds have Caliche clay. They add something to the soil to make it like cement. I was just informed that it has limestone in it to make it hard. They use it in stock ponds to hold the water. I have amended the soil for 10 years. We dug out 18 inches of that stuff in a bed last year and put in hundreds of dollars of landscape mix and topsoil from a local nursery. This year I was having problems in the front of the bed, when I dug down 2 feet, water was standing in the hole and within 10 minutes 4-6 inches of water was in there. You cannot ammend it. I don't know how deep it goes
I do have a compost pile and may try the willow.
Nancy, it's the aged stuff that landscapers use.

This message was edited Jun 17, 2010 10:07 PM

Well you may have hit the nail on the head here. The method you describe was / is used to keep water out of a house basement, and is used to raise the ground around a house to help to that end.

I have seen it, that a new home site is even filled with rock sometimes 1 to 2 feet all around a house, dirt is brought in and then sod is put down. Since it is a new house people do not expect to see mature plants and never think to "dig" or to ask what is in the ground.

If one has a raised septic system in the back or side of the house, one can assume there is a high water table. It certainly sounds like that is your situation. Frankly removing the dirt, may put in a position where you will have water in areas that you do not want. On the other hand it may just be that the folks that built your house found that is was cheaper to do this type of fill rather then to give you good top soil.

The method I gave you works fine for small beds and for terraced beds. For a terraced bed just make one section large say 10 x 10 and then the next 6 x 6.. putting the smaller one on top. You will get a different look, and be able to have some plants hang over the edge. Run a water line in the middle and sink the hose in the ground, put a sprinkler head on the top or a fancy water thing, make sure you can turn the water on and offf close by but away from the sprinkle when the water is on, and you will have a thing of beauty to look at.

You can also do this with the borderless mounds but usually the area should be bigger, and as you said the ground is clay, if you can manage to use this type of medium, you could almost make a mini pool, with garden inside instead of pool water.

Gosh I wish you my best, as I know what a hard time you are having. I would send you roses if I could so I will do the next best thing.... Enjoy my peony.

Nancy.

I wouldn't have guessed that was a Peony. It's pretty.
Thanks, for such great ideas. It got to 108 degrees last week, so I will have to work early in the morning and late in the afternoon. A lost of plants need to be dug up.

Ange--I live in Pearland TX, where all my "soil" is black, sticky clay--good organics in the clay, BUT almost no permeability--probably like your soil. Raised beds are all I do for annuals & perennials. Easy method: put 8-10 sheets of newspaper directly atop grass, then put your raised bed sides on top of that, then fill with good flowerbed soil, plant flowers, and top with 2-3 inches of mulch. Materials for sides of raised beds: if your plants are not for human consumption, you can used treated landscape timbers. Stack 2-3 on top (alternating like bricks), drill a large vertical hole where the timber ends are, and "pin" the timbers with a piece of re-bar. For temporary raised beds, I have also used concrete builder blocks. If you want to pay more and have a better-looking bed, go with Pavestone or natural rock you get from a landscape supply store. When we plant trees and shrubs on our property, we always dig a big hole--as deep as the rootball, and 2-3 times as wide as the rootball--THEN we mix the "soil/black clay" that came out of the hole in a wheelbarrow with water and pelletized gypsum--about 5 parts of soil to one part of gypsum (NOTE: make sure the sides of the hole are "rough" and not smooth--don't dig a "pretty" hole). Use enough water so that you can pour the mixture from the wheelbarrow into the hole. The gypsum helps break down the clay and makes it easier for the tree or shrub to put out roots. If you dig a hole in our clay "soil" and plant your shrub in it and use good garden soil to backfill the hole, the good soil acts like a sponge and all the rainwater makes a beeline for the "sponge", and your shrub will drown in a hole which becomes filled with water. Good luck!

Thanks, for the great tips.

amgedawn47 here is a picture of a raised bed my DH constructed with stone bought from the hardware store. Its on a slope but works well until you get the mower stuck in the drainage ruts LOL Thought you would like to see, started out as flower bed, but when ya can't dig anymore a nice shrub is what the dr. ordered.

Hi Ange, I live in NE Louisiana. Sounds like raised beds are the only way to go for you. I am a raised bed gardener. I raise vegetables in mine because the soil where I have room for a garden just isn't any good. I have 3 raised beds in my yard that I built about 20 years ago out of landscape timbers. They will eventually rot but it takes a long time. The ones in my yard have deteriorated now but you see how long they have been there.

When I build one with landscape timbers, I cut off the first long timber about 4 inchs. I come all the way across with the end pieces and toe nail them to the long piece. The next long piece I leave full length and set in on the first and nail straight through. I cut the top end pieces to fit and nail straight through to the bottom piece and toe nail into the top piece.

I fill the bed with compost and plant. With a raised bed you have to water more regularly because it won't hold moisture as good as the ground. You also don't have to worry about over watering because the overage will seep out the bottom.

For an edge around the beds, I spray a couple of inch border with round up. You can lay a board down or a landscape timer to give you a good straight edge. Then I just go back a couple of times during the summer and burn off the ends of any grass runners that try to creep into the border.

I've found that two timbers high is sufficient for flowers. For veggies I build three high.

Thanks, Jim and what a small world it is. My parents live in the country between Delhi and Winnsboro. They have a Delhi address and phone number, but live closer to Crowville. I was just there this past weekend working on corn from the garden.

I try to get up there as often as possible to help out where I can and to check on my parents.

D-mailing you.