In the September/October 2009 issue of Gardening How-To, Michelle Leise wrote about some techniques for conserving water in the garden. But how you use water effectively has a lot to do with what kind of soil you have: clay, sand, loam, or something in between (like clay loam, silty clay, loamy sand, etc). To find out, grab a quart jar and a shovel and follow the steps below.
Just add water
Fill a quart-sized glass jar (a recycled mayo bottle works well) about halfway with soil from your garden. Add water until the jar is nearly full. Give it a really good shake—there should be no clumps left. Now, put the jar on a level surface where it can remain undisturbed for 24 hours. You’ll want some light for this part, so don’t tuck it into a dark corner.
Wait and watch
Sand will be the first ingredient to drop to the bottom. This doesn’t take long—just a few minutes. Make a mark on the jar at the top of the sand. Silt particles will sink next. This takes several hours. Again, make a mark on the jar. Leave it alone overnight before you check for clay. The water may still be cloudy, but you’re ready to mark the level of clay in your soil.
What it means
To make sense of the info in the jar, estimate a percentage for each layer. Next, visit the soil-type triangle http://www.westone.wa.gov.au/toolbox6/hort6/html/resources/depot/hort_file/pyramid/text_alt.htm. At first glance, this resembles the Bermuda triangle—complex and indecipherable. It is not. Just follow the directions and you’ll find it’s surprisingly simple.
Now that you know how much sand, silt, and clay is in your soil, you have two choices. You can amend your soil or learn to love plants that grow in your soil type. To amend either clay or sandy soil, work in plenty of composted organic matter. Your plants will thank you.