Dry-stall vs Horticultural pumice ... was algae and moss in seedling pots
Hannon (Wed, 01 Feb 2012 16:31:40 PST)

Since so many growers here like to start their seeds indoors, by necessity
or preference, it may be worthwhile for them to set up a small low rpm fan
to drift over the seedbed or seed pots 24 hrs (or most of the time). This
would help reduce excess moisture retention, which seems to be the main
issue as far as algae, etc. It would also improve the general air exchange
and circulation in any enclosed space at a low cost.

Normally I sow in small pots (3" or 4" square) in a mix of sharp sand,
rather fine perlite and rather fine peat, in descending order but not
precise proportions. I find it beneficial-- very important actually-- to
top off the pot (when completely finished) at or very close to the actual
rim. I add an obligate layer of fine granite that is roughly no. 10 grade
(used in roofing here). With a few exceptions these pots all get free or
limited rain exposure and limited direct morning sun and this suits a wide
range of species quite nicely.

The algae and wetness are, I think, mainly, a function of too much watering
and (mostly indoor) conditions that do not allow proper drying.

Dylan Hannon
Los Angeles

On 1 February 2012 15:57, Tim Chapman <tim@gingerwoodnursery.com> wrote:

--
Where there is much desire to learn, there of necessity will be much
arguing, much writing, many opinions; for opinion in good men is but
knowledge in the making.
— John Milton, *Areopagitica: A speech for the liberty of unlicensed
printing to the Parliament of England*, 1644