I did put lava sand down on our lawn once, but not sure if it helped or not. I also used expanded shale in a new bed, but I think the compost I added is doing more for the plants than the expanded shale. I am a big fan of adding compost since that is the thing I see making the most difference in my gardens.

Have you had a soil test done yet, Mary? That is the only real way to determine what your soil might need. Most clay soils in this area are not deficient in micronutrients, but the high alkalinity can prevent plant uptake of certain nutrients. The best all around additive is compost, it's hard to get too much organic matter.

Not lava sand, but other sand. We had an above ground pool in our hard clay backyard soil & took it out this spring. It had a layer of whatever kind of cushion sand the pool co. used. We got 4 yards of compost & then dh tilled it all up. It's amazing how easy that part of the soil works now. The part around the edges that is still just clay is hard even after tilling.

Lava sand and expanded shale work wonders in a bed to break up clay soil and improve water movement and stop wet feet. As a result, the critters in the soil get more air and everything works better.

lakedallasmary- with all due respect, you don't need to do your own controlled tests, because universities do these all the time on a large scale. Professional plant scientists with academic credentials uniformly agree that adding such exotic soil amendments as "lava sand" may make the gardener feel better because she is "doing something," but there is no positive effect to be gained. If you feel your soil lacks "trace minerals," adding good quality loam is the best route to go. Adding decaying plant matter, such as leaf mould, will certainly enrich your soil and make it more friable. Depending on the results of a soil analysis, fertilizing as needed with either a slow-release 20-0-0 or 20-5-10 should give your plants or turf a boost from time to time.
There are gardeners who scoff at the idea that professionally trained experts give the best available advice, and prefer to take the advice of Grandma or some "self-taught" radio show host. That is certainly their privilege and none of my business.
However, if any of these people are unfortunate enough to contract cancer or diabetes or tuberculosis or another serious disease, they are likely to seek treatment from a professional physician rather than go on what a neighbor tells them or what they hear from just anybody on the radio.
We listen to experts when it comes to many things. Would that it be so with gardeners.

I have used lava sand for years and I love it. In my pots it helps to keep the plants moist but in my beds it helps to keep the water moving. I have also used it to fill up the cracks in the soil when it gets bloody hot in the summer. Well, actually I mix it up with compost and shredded t-shirt bits. ;)
All I can say is try it out. I refused to pot plants without it but that is just my two cents.
Have fun!
Christina

Greensand is very good. It has lots of trace minerals and adds iron.

I like to use humax or humore when I'm planting new plants. I just mix in a handful or so to the backfill. I can really say it makes a big difference. It's too expensive to use in the whole bed $10/40lb bag, and I use compost to improve the whole bed, but either of these products really boost new plants. I also topdress certain plants with it every couple of years.

Where does one get lava sand?

Deanna

I'm a tightwad with gorgeous gardens. Every year I catch the tree trimmers clearing the creeks for the power company and have them dump a truckload of mulch in our driveway. A full 1/3 of it is usually leaves. We add a thick layer to all the beds and around the trees at the beginning of each summer. I seriously don't even fertilize anymore. I get all that mulch/leaf matter free and buy a $17 bag of nematodes. That's it.

In the veggie gardens, at the end of the season, I put whatever is under the chicken coop (nastiness and muck) in the cleared gardens along with the rotting leaves that fall in the street from our neighbor's pecan trees. Stir it all in and wait for spring.