We live on a hilly/rocky clay soil. We are going to dig down to make it level for a garden and add sides for a raised veggie garden. To this we are adding top soil and compost. We are going to till this together. My question is how deep should this be? We will be planting tomatoes, peppers, cucumbers, squash, onions etc. Does anyone know how deep the roots go?
Making A New Veggie Garden
off the top of my head i would say at least 18 inches but someone will come along to give you concrete answers
I'm just a little north of you, near Springfield, MO. I built my beds 16" high, and had 8' tall tomato and okra plants last year. Now, the sides were 16", but the bed was dug out about 3 or 4 inches more than that. The bottom was also loosened up thoroughly before I started putting the soil blend in the boxes, so that there was no stratification. I put down about 2 inches of creek sand and then the soil blend on top. Add some creek sand and rice hulls to your recipe. My beds are about 40% top soil (the best I could find), 40% organic matter and 20% creek sand. My organic matter was mostly compost from Springfield's yard waste recycling center, with composted herbivore manure from the zoo and rice hulls added. I topdressed with more compost and rice hulls this Spring.
Does Brighton have the same rocky/clay soil as we do in Northwest Arkansas?
We surveyed the ground yesterday and had to take out 18" on one side for it to be level. Our garden plot is 15' by 15'. We are adding compost we have made this winter and what they call top soil here, which is soil without the rocks! I think I can get some rice hulls around here but is there a reason for them? Does it keep the soil loose? We need all the help we can get.
Camakin,
I built four beds 4' x 4' in about the same amount of space you're looking at. If you're considering 4' wide beds the full length of your plot, that would work, too, and would give you significantly more growing area. The square beds have wonderful access, but waste some space. I built them that way to use some found materials.
Yes, our soils are quite similar. Let's put it this way, I just screened the tilled up soil for my garden expansion of about 1,000 square feet. I'm estimating that I screened out a ton to a ton and a half of rocks.
Unless you've been working on that compost pile for years, I am going to guess that you don't have enough. It needs to be a bare minimum of 33% of your blend. Not sure where Garfield is, but if Springfield is a reasonable drive, the city has great compost for $15 a cubic yard. Rice hulls keep the soil aerated and add additional organic matter.
In excavating your plot, consider that it isn't necessary for both beds (or all the beds) to be level with each other, only that each bed be level itself. All four of my beds are at different heights. The grade was changed enough that the paths between the beds are comfortable to stand and walk on, but not perfectly level.
"How deep the roots go" is way deeper than 18 inches, but 18 inches deep for a bed that is resting on soil should be fine -- because the prepared, compost enriched top of the bed will interact with the clay/hardpan and the planting depth will increase as you go, as long as you keep adding compost and do not compact the soil with too much walking on it or use of heavy equipment. Of course that will do nothing about the rocks in there but if the soil around the rocks becomes softer and workable, as it will, the roots move around the rocks....... and the rocks move too! And very very slowly they also leach their valuable minerals into the soil, and good rich soil is what lets them do that.
A tomato has a huge huge root system. It can spread out, or it can go deep, the tom does not seem to care which. But the more good soil available for each plant, the larger the plant will grow.
All that said, I am in a new process of doing all veggie gardening in containers, so trying to balance size of container, contents, price range of all parts of the system, basic plant needs etc! Obviously containers more than 18 inches deep are right large ones!
And I do think 18 inches deep for a raised bed is a healthy start at least.
Thanks for the advice. Our compost is about 8 feet tall and 12 feet wide. My honey mows grass, so we have a lot of leaves and grass that we compost. But there never is enough!
We were really successful last year with our "square foot gardening" method http://www.squarefootgardening.com/index.php/The-Project/what-is-square-foot-gardening.html
We grow in 6" of mel's mix. It's crazy but it works. We're doing it again this year, doubling our gardens.
Julie
Tomato roots can reach two and even three feet:
http://www.soilandhealth.org/01aglibrary/010137veg.roots/010137ch26.html
But then people grow them in containers a foot deep.