Nerine and Oxalis Starvation diets

Brian Whyer
Sun, 06 Nov 2005 08:07:05 PST
> Out of about a hundred N. sarniensis crosses, this year I have had the
> fewest flowers ever,too. Nine have bloomed, and most bulbs have become
> smaller. I plan to experiment over the next year, Brian, I like your
> about 2 litre pots, and soil based you believe in soil
> sterilization or do you, like others, feel that it kills too much


My potting mix for all my plants that are to remain long term in pots,
is a mix of commercial soil based multi purpose compost, lime free grit
and a composted fine bark, plus on occasions vermiculite or Perlite
instead of the grit. The commercial compost is a loam/soil + sphagnum
peat + grit mix, with fertiliser and trace elements added, similar to
John Innes no. 2 or 3 but probably with a higher peat content. I guess
that with my mix, that varies in proportion depending on what I am
potting, the final soil/loam content is not much more than 10-15%, and
the grit content maybe 40%+. I use variations on this mix for most
bulbs, alpines, woodlanders etc. maybe adding a coarse sand with the
grit, and less bark, when it comes to the smaller South African bulbs
like lachenalias, or for some of the higher alpines cushions.
I find using potting bark gives a much more open mix than I ever got
with peat, when used in a soil/grit mix, but this is only available in
the UK "for propagating" as a trade product, so I have to search for it,
although a similar less well graded retail garden soil improver is
passable, but usually contains more fibres and wood splinters. By fine
bark I mean 2-10mm or 3/8" if possible. The soil improver is more like 0
- 20mm.

I was put onto a square 2litre pots supplier by Hamish Sloan. He like
me, uses them to give a good root depth, and to save space. Or maybe I
should say to get more plants into the same space, particularly when
much of the time they are just dormant leafless pots. I use smaller 9cm
square by 12cm deep pots for small bulbs and bulbous seed sowing, when
the seedlings may stay in the same pot for 2-3 years, for the same

I have noticed with my Nerine filifolia, which 2-4 years ago flowered
profusely, I now get none after neglecting them as regards fresh compost
and feeding. Lots of small bulbs but no flowers. They are too easy, and
got ignored. Similarly with the oxalis that multiply too quickly.

Brian Whyer, Buckinghamshire, England, zone ~8.

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