HelpfulGardener.com

Hello all!

In Orange County, CA.
I need to fill about 100 sqft., up to 8 inches in depth, in order to put in 4-3X10 garden beds which will be double dig with plan to add 6 inches of various organic matter.

What would be a great way to fill in this area which will be good as a base soil though in areas have a good composition to maintain its grade and support walking paths between the beds?

Thank you!

Is this a low spot in the yard where water collects? If the area has full sun and good drainage you should not need to fill in the whole area, just build and fill the beds. If the area is in a low spot and drainage is not good, it probably won't be a good place to put a garden in the first place.

The size of the paths depends on how much walking space you need or if you need a wider path for equipment. For people with limited space, paths are kept to a minimum. You can arrange the beds in a "U" or "T" shape instead of rows to minimize paths and maximize reach. Try to align the beds in a North South orientation.

If animals are a problem. You may need to have some kind of fencing or net protection.

Don't forget to leave a spot for the compost pile. You can start that now before you work on the garden.

Bed height really depends on the native soil and what you are planning to plant. Shallow crops like lettuce would only need a 4-6 inch bed if it is soft and well drained. Longer roots would need deeper beds anywhere from 10-24 inches deep.

If you are new to gardening, start small build one bed first and add on later. It will spread out the work and the cost. Sheet mulched beds will take 6 months to decompose before they will be ready for planting. If you start one now, it should be ready for planting next year. It is o.k. to have a master plan, just phase it in.

Soil mixes vary depending on your needs

soil mix 1
50% good topsoil + 50% blended compost

soil mix 2 (Mel's Mix)
1 part vermiculite
1 part blended compost
1 part peat moss

Soil Mix 3
Lasagna or sheet composting. It is explained including materials to build the beds in the link
https://extension.oregonstate.edu/garde ... composting

Soil mixes do not include fertilizer. You need to fertilize depending on the needs of the crop.

While you are building the beds, install the irrigation system to make it easier to water later on.

...yes... imafan has outlined some good alternative plans. Double Digging as a strategy presupposes a layer of existing good topsoil which will be re-stacked at a deeper level with the poor subsoil. In the process, you would add additional amendments and enrichments.

If you need to add 8 inches to begin with, then the ground you are working with is deficient, and I think it would be better to build up the soil over the beds. The paths don’t need the good soil. In fact I scrape up all the good soil from the paths to subsoil to put in the beds. My strategy for the paths is to keep them mulched with organic materials (put down pulled/cut weeds, yard trimmings, etc. and cover with cardboard, grass clippings, leaves, wood chips, etc. These break down compost in place, which then get scraped up into the beds....

There are other strategies for the garden beds, and I agree — Sheet Mulching and/or Lasagna Gardening are ways I am most likely to consider for adding organic materials and building up just the individual raised garden beds. If you don’t mind using chemical fertilizers, then you might also look into strawbale gardening (I haven’t found a way to effectively utilize this method in my garden using only the organic materials I have available.)

I would also incorporate hugelkultur or some derivative — I have never quite managed a full-scale hugelkulture, but simply buried small branches and sticks. Aged, already decaying wood is best. Adding fungal/mushroom symbiote would help break down the wood faster if using fresh wood or wood chips and straw as mulch. This is a good way to add bulk.

Each of these alternative methods will enrich the soil underneath the beds, and eventually, you will be able to try double-digging the organic material and soil that you have built up and which have developed/resulted into the existing subsoil. If you still want to try this in the future, don’t make the sides for your raised beds permanent. One easy way is to make the sides with heat-treated wooden pallets and skids.

Contact your local "Sand and Gravel" or "Concrete" distributor. It is likely they can bring you a dump truck full of topsoil. Look in the phone book for "Sand and Gravel" or "Concrete". Do you know a building contractor? Ask him for advice.

You talk about your beds. Here Dad had milk cows and he also had 150 acres where various feed crops were raised for the cows. He always saved a spot near the house that he called "The Garden" where he grew corn, beans, squash, etc. This area got fall and winter doses of manures from the cows and chicken coop. This was the fertilizer. There was no raised area. He just went out and planted in rows and later he would lightly till between rows with a hoe or hand pushed wheel hoe. Water came in a ditch and furrows were dug with a hoe and the water was ran between the rows. He usually got a good harvest. Gardening though has its risks and at times a weird change in the weather will mess things up. Usually something will do good. Sometimes it will all do good. You just gotta plant and hope.