Well-drained growing media (was Oh No! A Boophone disaster!)

totototo@telus.net totototo@telus.net
Sun, 04 Oct 2009 11:57:07 PDT
On 4 Oct 2009, at 10:18, Jane McGary wrote:

> I live where horticultural pumice is readily available.

As it is generally in the Pacific Northwest. Here in BC, all we can get is 
pumice from Keefer's Greenhouses in Vancouver, in plastic bags and costing the 
earth considering what a plentiful material it is. The pumice they sell is a 
dead gray-white that I find visually unattractive. I have to wash it over fly 
screen to get rid of the fines, which I have in the past found will form a 
layer at the bottom of a pot and totally block drainage.

In Washington state, Verkist orchid nursery outside Bellingham sells (or used 
to sell) both washed and unwashed pumice, the former in your choice of sizes. 
It's been many years since I was there, but the price was quite reasonable. The 
pumice they sold was a warm ocher yellow, very attractive.

I don't use pumice for my bulbs, perhaps because it's really over priced, but I 
do use it for high alpines, many of which seem to very much enjoy it. I have a 
large pot of Weldenia candida that has pretensions of becoming a cabbage!

> Our NARGS chapter in Portland recently heard a talk by Truls Jensen 
> of Wild Ginger Farm nursery called "Fresh air," which featured his 
> techniques for increasing air space in container soils in order to 
> grow xeric plants successfully.

Undoubtedly many of the subscribers to the PBS mailing list have at one point 
or another heard Phil Pearson and Steve Doonan's dog and pony presentation on 
the importance of air in one's potting mixes. The importance of the roots 
having plenty of air seems to be rather poorly appreciated, but Florence Bellis 
in her "Gardening and Beyond", published 20 years or so ago, urged gardeners to 
fork over their beds every spring to improve aeration. The principle is nothing 

Rodger Whitlock
Victoria, British Columbia, Canada
Maritime Zone 8, a cool Mediterranean climate
on beautiful Vancouver Island


More information about the pbs mailing list