I know what Clay is and I know what Sand is but what is loamy soil?
Is it just garden soil (as in commercial potting soil) amended with some mulch or other matter?

We throw these words out and expect the novice gardener to know what we are talking about.

Thanks for your help -- placing the thread here as I did not know where else to post it.

Marilyn: Loam is a combination of sand, clay etc:

http://www.hort.purdue.edu/ext...

http://en.wikipedia.org/wiki/L...

Thanks, I did google but guess I chose the wrong sites to visit

I like this explanation:
"Loam soils generally contain more nutrients, moisture and humus than sandy soils, have better drainage and infiltration of water and air than silty soils, and are easier to till than clay soils. The different types of loam soils each have slightly different characteristics, with some draining liquids more efficiently than others.

Loam is soil composed of sand, silt, and clay in relatively even concentration (about 40-40-20% concentration respectively). These proportions can vary to a degree however, and result in different types of loam soils: sandy loam, silty loam, clay loam, sandy clay loam, silty clay loam, and loam."

Again, some level of confusion when a plant description in the database says loamy soil it could mean, sandy, silty, clay etc Loam.

Thanks for your help

>> Loam is soil composed of sand, silt, and clay in relatively even concentration (about 40-40-20%

I think that is a good definition to pay attention to! It also has t\he connotations like:
- "easy for plants to live in"
- easy to till and maintains "tilth" once you've fluffed it up and firmed it.
- sufficient water retention
- well-aerated if not too compressed

It motivated me to go look up "silt":

"Silt is granular material of a size somewhere between sand and clay whose mineral origin is quartz and feldspar."

"loose sedimentary material with rock particles usually 1⁄20 millimeter or less in diameter;"

My guess is that the definition works out to "if you shale it up ,in a jar of water, sand drops right to the bottom. Silt settles slowly (minutes to an hour). Clay settles very slowly (if at all).

I like the fact that soil is best when it has "some of everything" and is middle of the road in every way..

Some solids, some water and some air.
Some sand, some silt and some clay.
Some mineral stuff and some organic.
Some living things mixed in with the unliving.
Variety of life: many tiny microbes, many small and medium fungi, tiny insects, some worms.

Enough water to be moist and keep the soil life alive, not so much water as to exclude air.

Enough air to keep soil life and roots alive, not such big voids that root-eating animals take up residence or subsurface water all evaporates.

Some "structure" meaning sticky enough to form crumbs, clods or peds, but not as sticky as pure clay.

Stiff enough to "stand up" and maintain a porous structure instead of slumping down into soupy mud. Not as stiff as rocks or baked clay.

Somewhat friable so you can m ix it and till it, but not so crumbly that peds or crumbs disintegrate, fall apart into dust, slump down and pack tight so air can't enter.

Tilled enough to create fluffy or 'crumb' structure, but not excessively tilled into dust.