Re:Madagascar lace plant

       From: "Michael E. Kane" <mek at GNV_IFAS.UFL.EDU>

>I'm growing Aponogeton madagascariensis (fenestralis) stock plants in tanks
>in a shaded greenhouse. We are plan on using these plants as a source of
>shoot tips for some tissue culture studies.  Does any one have first-hand
>knowledge of  the environmental/cultural conditions that will promote
>flowering in this species?  I would also like to generate seed.

I have had two of the three varieties of madagascariensis; the narrow
leaved one, given a separate species status (guillotii) by Muhlberg, but
not by other authors, such as Rataj or Kasselmann; and the madagascariensis
variety.  Guillotii, with its very large size and five-spiked purple,
self-sterile flowers is quite different from madagascariensis, with its
smaller size and two-spiked, white, self-fertile flowers.  Both bloom on a
long day (16 hours of light).  I have not seen the third variety,

One thing I have found that is necessary for good growth with the
madagascariensis variety is to have "companion" plants that are rooted near
the lace plant.  Small crypts, such as nevillii (now C. x willisii) are
good as "companion" plants because the lace plant can easily get its leaves
above those of its companion.

I got lots of flowers from guillotii, but never any seeds because I had no
second plant to use for cross fertilization.  I got lots of seeds from
madagascariensis, and they sprout readily, but are a bit difficult to grow
to a large size.  To start them, I recommend sand with a little mud made by
mixing topsoil with water mixed in the bottom layer of sand.  Small
companion plants may help here, too.  When the seedlings have leaves four
to six inches long or bulbs the size of a pea, they can be transplanted.

When seeds are shed, they are covered in a thin, water repellant jacket,
and they float for a day or two before the jacket disintegrates and the
naked seedling drops to the bottom.  I once got a seedling in sterile
culture by breaking open the jacket and letting the seedling fall in
sterile nutrient solution.  It grew to full size, flowered, self fertilized
and produced a crop of seedlings which also started growing well.  The
experiment ended when I got the nutrient solution contaminated with algae
while attempting to change it.

Paul Krombholz                  Tougaloo College, Tougaloo, MS  39174
Goofing off instead of working in pleasant, although cooler, Jackson,