Raised bed height?

[LlamaBeans]

I am starting a first year garden (not my first as we moved in Sept.) and we have decided to have raised beds. What I want to know is what depth they should be. We are willing to build different depths.

Here is what we are planting; Corn, Broccoli, Cauliflower, Pea, Tomato, Beans, Strawberry, Aspargus, Potatoes, Beets, Cuccumbers, Lettuce, Cabbage, Celery, Rutabega, Rubarb, Carrot, Melons, Pumkins, Brussle Sprouts, Pepper, Peanut, and Kiwi

Thanks

 

[vfem]

It's really about how deep the roots need to go. I went with 12" on all. I want to be able to rotate my beds each year with whats in them and rather then chancing having a bed too short for a deeper rooting plant, I just went with deep. We filled them with 100% or 50/50 compost/topsoil from a local landscaping company that only charged us $20 a truck load. $80 later we're good to go! A bag of 10-10-10 fertlizer is my back up.

Just a tip, I put chicken wire underneath them to let roots go down but keep moles and gophers from coming up!

Really, the heights are up to you though. I do have some that are for perennial flowers.... all only 4-6" raised.

 

[LlamaBeans]

We had planned on a minimum of 12 inches and a maximum of 18 but can go higher if needed. Thanks

 

[DrakeMaiden]

I have heard that most plants don't need more than 8-10". I would want to err on the side of more, though, especially because a deeper bed would retain more moisture in hot weather. I think 18" might be over-kill, but it depends upon what height is most convenient for you to work with . . . if you have a bad back and don't like to lean, 18" might work better for you.

 

[LlamaBeans]

We had planned on 12 untill I read somewhere that rot crops needed more but I don't know where I read that at. Thanks

 

[DrakeMaiden]

Well, that may be true theoretically, but are you trying to grow foot long carrots or 6" ones? I would think most garden veggies will grow w/in 12" of soil just fine. I have seen claims of longer roots before too, but when I pull up veggies, it is rare for them to have roots deeper than a foot.

 

[patandchickens]

Unless you're on bedrock or the equivalent, they will sink their roots into the soil below the raised beds (and should be encouraged to do so by roughly digging over that soil before you put the raised beds on top). To my mind, 12" is way plenty deep, and for most situations you don't even need that much.

Good luck, have fun,

Pat

 

[vfem]

If it helps we are putting in a triple decker raised bed. The first level is only going to be 6", the next one will be 12" and the 3rd level is 18". This is for strawberries on the bottom and random bulbs and some creeping type of plants for the rest of the levels.

I figured its not about the rooting system of the plants I'm using so much as nice to look at!

Just go wild!!! Do what pleases you... but I have to agree to break up the soil underneath it!

 

[LlamaBeans]

Hmm this might change things as we had planned on putting landscaping cloth down beforhand.

 

[patandchickens]

I don't honestly see any point in putting down landscape fabric under raised beds.

It will *not* fully prevent grass or other annoying perennial weeds' roots/shoots from getting into your beds -- and 'not fully' will equal 'not at all' given a year or two. (Plus grass will always sneak in anyhow if you have any lawn around the raised beds)

What it *will* do is block your on-purpose plants from sinking their roots into real soil where they can access extra nutrients and water.

There may be some obscure case where landscape fabric is worthwhile under a raised bed but I can't think of it offhand so on the whole I would really advise against it.

If grass is your main concern, I would suggest smothering the grass as much as possible to weaken it before you build the raised bed, and then digging the sod upside-down, topping it with enough compost or manure or whatever to level the surface, putting down a couple good layers of cardboard, and then building the bed on top of that. The grass, heavily weakened by your inverting the sods, will exhaust most or all of its energy trying fruitlessly to grow up thru the cardboard; and by the time your plants' roots grow donw that deep, the cardboard will be decomposing and the grass as dead as it's going to get.

JMHO, good luck and have fun,

Pat