Sounds like a terrific project to me :) just one question, why are you mowing the lawn as short as possible? If you leave it long and dig it out & turn it upside down the extra grass will provide added nitrogen to the soil as it breaks down. Just a thought, good luck :)

I too wonder why you plan to mow the grass as short as possible. There is no need to do that. You can turn the sod over or cover the existing sod with newspaper/cardboard, but there is no need to mow it close.
There is no need to wet that layer of mulch, it will do its job better dry. All in all your plan looks good, although a good reliable soil test would be something I would have done as well as these simple soil tests,
1) Soil test for organic matter. From that soil sample put enough of the rest to make a 4 inch level in a clear 1 quart jar, with a tight fitting lid. Fill that jar with water and replace the lid, tightly. Shake the jar vigorously and then let it stand for 24 hours. Your soil will settle out according to soil particle size and weight. For example, a good loam will have about 1-3/4 inch (about 45%) of sand on the bottom. about 1 inch (about 25%) of silt next, about 1 inch (25%) of clay above that, and about 1/4 inch (about 5%) of organic matter on the top.

2) Drainage. Dig a hole 1 foot square and 1 foot deep and fill that with water. After that water drains away refill the hole with more water and time how long it takes that to drain away. Anything less than 2 hours and your soil drainsâ too quickly and needs more organic matter to slow that drainage down. Anything over 6 hours and the soil drains too slowly and needs lots of organic matter to speed it up.

3) Tilth. Take a handful of your slightly damp soil and squeeze it tightly. When the pressure is released the soil should hold together in that clump, but when poked with a finger that clump should fall apart.

4) Smell. What does your soil smell like? A pleasant, rich earthy odor? Putrid, offensive, repugnant odor? The more organic matter in your soil the more active the soil bacteria will be and the nicer your soil will smell, to9 a point. Too much organic matter can be bad as well.

5) Life. How many earthworms per shovel full were there? 5 or more indicates a pretty healthy soil. Fewer than 5, according to the Natural Resources Conservation Service, indicates a soil that is not healthy.

Your plan seems reasonably complete but I would change the order - site prep first (clearing out any existing plantings, layout of features, grading/excavating, lasagna conversion), then the hardscaping. Planting is always the last step in a landscape renovation other than any mulch application.

Not sure what kind of lawn type you have now, but if a Bermuda grass, the lasagna method is not gonna work. Even digging out the sod and flipping it over and piling on other layers will not kill the Bermuda. It will remain around forever and create a huge weedy grass issue. If a Bermuda grass lawn, you will need to kill it off somehow before attempting the lasagna layering. Otherwise, I agree that mowing the lawn short is not a requirement but might make work easier.

Roger's Gardens in Corona del Mar holds a 'California Friendly' gardening contest each year. These are conversions of water consuming landscapes into eco-friendly, drought tolerant but still lush and attractive waterwise and fire retardant gardens. Whether or not you choose to enter the contest, looking at their album of gardens from previous contest years could be a great inspiration. And they carry a wonderful selection of appropriate plantings. Worth a Sunday drive for a visit if nothing else ;-)

And I'd suggest you post in the regional California Gardening forum your request for sources for materials. Locals will have a much better idea of directing you to appropriate vendors for your needs. Craigslist is a good resource as well.

As I stated in your previous post, this is really more of a landscape design issue than necessarily one just focused on soils or organic gardening. You've got the concept nailed down pretty well..........it's only the methodology (organic or not) that is up for discussion and it is certainly possible to accomplish your intent without resorting to chemicals.

But don't get too wound up in the "organic" mindset. Sometimes this terminology can get confusing and interfere with the most efficient process to achieve your intent. This is more an issue of sustainability or designing your garden to accommodate your climate with minimal input and recycling materials to create the effect you want. And the recycling can/should include the hardscaping and mulching as well as the lasagna layering.

Here is a link that might be useful: California Friendly gardens

Hi,

You might want to have a look at John Kohlers videos, start with the oldest ones first, he converts his yard in Las Vegas into a garden in them. Here is one of his first ones:

Here is a link that might be useful: Growing Your Greens

Thanks, that's all good info / advice. The part about cutting the lawn short as possible was from something I read on lasagna gardening, not sure where though as I have read a lot and it is not always consistent.

I had done the drainage test, but in the LA County guide on gardening, it said you WANT the 1 foot hole to drain in less than 60 minutes, or you should amend by tilling or augering. Ours took 90 minutes to 3 hours in various parts of the lawn, and we looked into tilling or augering, but read negatives on each, and also read some people saying this drainage is not too bad. Also, I read that if the soil has the right "life" in it, it should naturally amend itself, so I got the impression that if our lasagna technique adds substantial life to the soil, that ought to help the drainage in a more natural way. So, anyway, we were just going to convert the yard without augering or tilling, and hope for the best. If we had continuing problems due to drainage, we figured we could perhaps do some "spot augering" after the conversion. The yard won't be wall-to-wall plants, so there should be spaces to auger without messing up the plants.

Ken

Every thing I have seen on soil drainage says water should drain from that hole (1 foot in diameter and 1 foot deep) at the rate of about two inches per hour.
Life in soil depends on the amount of organic matter and in clay soils organic matter separates the clay particles so water can flow easier. A Lasagna bed will, eventually, cause enough organic matter to build up in the soil underneath, but that can be several years in the making. The reason clay soils do not drain well is lack of organic matter, the clay particles lock together and do not allow water to flow through easily.
Solve the problem, add organic matter, and drainage will improve.

Here is a link that might be useful: soil drainage