pumice

Ina Crossley klazina1@gmail.com
Wed, 21 Oct 2015 11:41:38 PDT
Growing Zephyranthes and Habranthus and various Amaryllids, I have had a 
real problem with Staganospora curtesii.  I realised that it was winter 
time which seemed to be causing the biggest problem.  As the bulbs never 
got dryish.  Being outside.

So I changed all the containers to a mix of 2/3 pumice and 1/3 potting 
mix.  Which did not give much of an improvement.  So even though it was 
a huge job I decided to redo the whole lot again this year using pure 
pumice.  New Zealand pumice has been washed but still has lots of fines 
in it.  So I rewashed every bit of pumice I used.  Started with a cubic 
meter of the stuff, but now buy bags of it as I am nearing the end of 
the job.  I now use 7mm pumice, although the cubic meter lot was smaller.

I add slow release fertiliser to each container.  And the bulbs are 
doing fine.  Yes, they grow more slowly, but they are healthy.

Quite a lot of the sick ones I threw out and have started growing fresh 
lots.

I have not had to water much as winter time is a wet season.  But once a 
week I water with fertiliser.  And now going into summer, I water when 
required.  Also I have passed tape through holes in the side of the 
containers to help drain that water table at the bottom.

A few like Z. atamasco and Z. simpsonii have their own requirements so 
those I now grow in the bog garden.

And some desert ones, I have put the containers against the house so 
they stay drier than the others.

I grow lots of other bulbs which do not get pure pumice.

I think we all have to find what suits our climate.

Auckland has a subtropical climate and it gets humid in summer.

Ina Crossley

New Zealand



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