On Thu, 27 Mar 2003 18:34:24 -0000, "hayley"
wrotc:

Is it possible for a male holly to have any berries? I've got several
hollies, some of which I bought from reputable sources as male (named
varieties - and I know that you cannot tell the sex by the name, these were
ones which said "a male holly ..." on the label). The first year I planted
them all in the garden I had lots of berries on the females, none on the
"males". Last year far fewer on the females, a few odd berries on a couple
of the "males". This year just a fine sprinkling of berries on all of them
(both sexes) bar one (male). Can they change sex?
Hayley

Cannabis sativa is a dioecious plant.

Those who grow it for its psychotropic properties have in recent
years developed a style of growing called "sin semilla" (without
seeds). This requires identifying the sex of seedlings as they flower
and promptly removing all the male plants.

Some plants identified making a first showing of female flowers
occasionally (and some cultivars were more prone than others),
subsequently and surreptitiously produced male flowers as a nasty
surprise. A hermie!

Window sill and lazy growers don't like going through the palaver
involved with the segregation of the sexes and some seed companies are
now producing what they call "feminised seeds" with a (legally
qualified) assurance that almost all the seeds would grow into female
plants.

The plants aren't female, they are in fact stabilised hermaphrodites
where the male flowers are purported to form really late so the seed
has no time to set. That is what one of the companies says.

Not so long ago (whether or not it was a scam I don't know as I
never heard of anyone having satisfactory results), a firm produced
something which, rather ridiculously, included the words "magic" and
"liquid" in the name. It was purported to be a pre-treatment soak for
seeds which would feminise them. It smelled extremely powerful on the
chemical front and reminded me of school days in the chemistry lab and
the smell of the fruitier aldehydes.

So, reaching the tail of a shaggy dog, when you ask (in respect of
Ilex):

Can they change sex?

I suggest that it may be possible to manipulate their sex and that
perhaps, only perhaps, when order is restored and they aren't stressed
out by this or that, they will resort to the predisposition of their
gender chromosomes.

Hermaphrodism, as a response in dioecious plants is, I believe, a
safety measure. Perhaps it sacrifices the benefits of a good genetic
mix with a guarantee that seeds will be set come what may - short of
conditions getting sufficiently harsh to cause an early demise.

This knowledge has made me quite circumspect with people who sell
dioecious plants guaranteed to be once sex or the other unless it is
already proven by flowering.

With regards Holly in the wild, is there a preponderance of one sex
over the other? Did the nurserymen get fed up binning so many (already
fairly mature) plants?

Those who are more clued up in botany might be able to comment on
whether the following blurb concocted by The Dutch Passion Seed
Company makes any real sense or whether it is a load of flannel for
the gullible: For me the telling phrase is " ..... except for the
predisposition in the gender chromosomes".

It all sounds to me like enforced perversion. A genuine and content
female being bagged by another genuine female which has been stressed
out to the extent that she has resorted to acquiring a few male gonads
and making it with anything that slightly resembles (including self).

The produce of this union? Apparently a load of babies who want to be
girls!

quote
In an experiment done in 1999 we grew 15 varieties of "feminized"
seeds. We started with 30 seeds per variety. The goals we 1) to
determine the percentages of female, male, and hermaphroditic plants.
2) to compare the uniformity (homogeneity) among plants from
"feminized" seeds with those grown from "regular" seeds.

1. The results were excellent. Nine out of fifteen varieties had 100%
female offspring. Percentages of female plants from the other 6
varieties were between 80 and 90%. These plants were all
hermaphrodites, producing their male flowers at the end of their life
cycle. Seed-setting hardly took place. No males were found.

2. Approximately 70% of the plants of varieties grown from "feminized"
seeds were far more uniform than plants grown from "regular" seeds of
the same variety. About 20% of the varieties were a little more
uniform, while in 10% of the varieties no difference in uniformity was
seen.

From literature and our own findings it appears that the growth of a
male or female plant from seed, except for the predisposition in the
gender chromosomes, also depends on various environmental factors. The
environmental factors that influence gender a

a higher nitrogen concentration will give more females.
a higher potassium concentration will give more males.
a higher humidity will give more females.
a lower temperature will give more females.
more blue light will give more females.

Fewer hours of light will give more females. It is important to start
these changes at the three-pairs-of-leaves stage and continue for two
or three weeks, before reverting to standard conditions.

To produce our feminized seeds, we start with selected female clones.
Under standard conditions these female clones do not produce any male
flowers. By the method we found, [ed. ermm, Yes?] we are able to have
these female clones produce abundant male flowers and pollen (see
photos). The pollen thus produced we use for the production of our
"feminized" seeds.

/quote

So when I am looking for a partner for my Rhamnoides (once I know
what sex it is), how seriously can I take the following:

Cultivars available:-
a) 'Leikora' (female) developed in the former East Germany.
b) 'Pollmix' (male) a selected pollinator.

?

Huss


Grow a little garden