Nerine and Oxalis Starvation diets

Matt Mattus
Sun, 06 Nov 2005 05:39:55 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 idea
about 2 litre pots, and soil based you believe in soil
sterilization or do you, like others, feel that it kills too much bacteria?

I must say, that after switching two years ago, to a more traditional "bulb
method" of growing my Oxalis, I can't believe the results I am seeing this
year. I will post a photo on the Wiki  today. I used to follow a recommended
method of growing bulbous South African Oxalis lean, in pure sand and
pumice, with no fertilizer, but they rarely bloomed beyond the first year of

Then I switched to a fast draining soil mix of

20% perlite, 10% builders sand, = 30%

which I mix with a 

30% mix of Pumice and/or granite gravel and

30 percent Pro Mix, which is a soiless peat based professional growers
medium, and 10% potful unsterilized soil from the garden.

These are rough measurements, not as complex as it seems, but my point is
that there is a percentage of organic material along with soil, and still
fast draining. Hey, we are all experimenting, right?

I also overpot the bulbs, by centering a cluster of bulbs tightly in the
center of the pot, then surrounding them with 'faux bulbs' that are actually
granite rocks roughly about the same size. I use this method with many bulbs
that seem to like being planted shoulder-to shoulder but are too expensive
to afford a whole pot-full. Also, it presents a more attractive presentaion,
especially with some Oxalis, (O. Luteola) which look like fine alpine
primula when grown this way. Visually, with a topping off of gravel, they
look much nicer too.

As for fertilizer, I, of course avoid nitrogen beyond bonemeal and
thunderstorms, and have switched to using a dry form of Potash (Potassium
Oxide K20) Which is 39%K in you analysis. The pots also get a bit of
bonemeal, that I integrate into the soil while mixing above mix. I should
count the nutrition of rainwater during the more milder autumns (like this
year) since I place them outside for their first watering around the first
of Sept., and they are allowed to stay outside in full sun to develop
tighter form in full sun, until frost threatens us. The plants are moved
underglass during the winter and dry summer, from about November till April,
the night temperatures are at about 40 degrees F. (5 C).

This is the same mix I use for most of my bulbs, especially my Narcissus
romieuxii and related Narcissus, as well as Cyclamen, and other South
Africans such as Romulea, most Lachenalia, Cyrtanthus (where I use more
loamy garden soil with gravel) and Rhodohypoxis. All bloom well for me, in
fact, I have three large Cyrtanthus elatus hybrids blooming, one in a 6" pot
never repotted, it's sister in a large 5 gallon pot to see if pot size
matters, it too is in bud right now, but has many more offsets, and another
in an 8 inch clay pot, also in bud.

Of course, there are many more factors here, light, winter temperature,
summer temperature,etc, but at least with bulbous Oxalis, I can clearly see
the difference. I even have a good bloom set on my O. pockockiae which has
never bloomed for me. Many that have not bloomed for me are blooming this
year. I am thrilled, and they are not floppy and big, nor oversized. Now, if
I can only get them to propagate!

Matt Mattus
Worcester, Massachusetts
USA zone 5a
Where we still have not had a yet!

On 11/6/05 6:59 AM, "Brian Whyer" <> wrote:

> "During the growing season, I water with a liquid fertilizer on every
> occasion, when the pots dry out from the previous watering. Overwatering
> is 
> death to the roots and the bulb will regress. I hold no truck with those
> who have advised in the past that nerines do well on a starvation diet."
> Brian Whyer, Buckinghamshire, England, zone ~8.

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