Biting the Dust - Literally.
 

Sydney woke up to this today:

http://beta.images.theglobeandmail.c...242781gm-a.jpg

A big dust storm blew through and coated everything in a thin film of red dust

It's supposed to be fine clay particles from the soil and dry lake beds in the Western Plains.

Anyway it looks -exactly- like the dust you get on LECA balls, it's exactly the same colour, consistency and it's just as difficult to wash off.

The thing is, various scientist types have been telling people that it's packed full of nutrients and will actually be good for gardens!

So this is my question.. if this dust is the same as the dust on Clay Aggregate, why do we wash it out and why don't roots (supposedly) like it?

It's not the same. Your dust from the storm would be natural, raw minerals having the crystal lattice faces available to the environment where they can be slowly dissolved by water in the soil, and taken up by plants. The dust on LECA is fragmentation of fired clays, bonded through the formation of glasses or the sintering of adjacent crystals, both of which renders them far less soluble - essentially not at all.

Mineral powders are generally to be avoided on epiphytic roots - they are just too desiccating. Dip your orchids in the dust storm residue, and the effect will be the same.

G'day.

Heard about your storms on the BBC this morning.

Reminds me of the stories of the "Dirty Thirty's" here in the US. It wasn't until the dust from the dust bowl in Kansas and Oklahoma, half way across the continent, started settling in Washington, DC that Congress decided to do something about it. And the Soil Conservation Service, now Natural Resources Conservation Service, and several other USDA conservation agencies were born.

Cheers.
Jim