Fw: Re: germination and growing technique

Some on this list have requested me to describe further my germination method
for bearded Iris seed.  This will also include how I grow them as well.


OK here goes... from beginning to end.  You can pull bits and pieces or all of
it
for your use if you like.  It may seem complicated, but it really isn't once
you
understand what is going on and have done it once yourself.  Also, it does
have some very minor typo corrections and clarifications to what I had
previously sent out to the offlist inquires from individuals (Adam and
Kathy).

     First thing that happens is that I harvest pods that are just starting to
split, or
close to it based on how shriveled they are.  Then I either put them in
envelopes
in a box or on sheets of paper to dry depending on how many I have and space
available.  If in envelopes they need to have a fan blowing over them so they
don't mold.   When they are dry I place them in Ziplock snack bags that I have
punched small holes in to allow for water and air circulation (important
later).  I used to use
the Ziplock vegetable bags that already had the holes punched in them and came
in smaller sizes, but they have stopped making them.   I then put the bags in
an
airtight plastic (preferable) or glass conatiner and place them in the fridge.
MAKE
SURE TO KEEP EVERY CROSS LABELED ALONG THE WAY if you are keeping
track of that information ( I don't know whay you wouldn't).  I would place a
plastic
or other appropriate tag with the cross written on it INSIDE the bag as
opposed to
writing on the bag as the writing may rub off.

     I plant my seedlings out in Spring around May (after all danger of
frost).  This is
important to know this because I germinate my seeds in the refridgerator and
will
explain this in detail. I also need to describe how I grow my plants first as
it is
rather more labor intensive than what I think many others do, but I like it
and it works
for me.

     I grow them in 96-cell bedding flats.  That there are 96 cells is not
that important,
just the size of the cell.  A larger cell (less cells per tray) would work
better also.
I wouldn't go any smaller on the size of the cell.  When I plant the seedlings
out in
the plot they have well developed root systems.  They have formed the thicker
roots,
developed a small rhizome/bulb and have proven to have less shock, stunting,
and
death when planting out in the plot.  Many of them will also bloom the very
next
Spring, and I have had a rebloomer or two bloom THAT FALL if they grew well. I
grow them indoors for about 3 months under very bright flourescent lights
about 6-8"
above them.  I then allow them to adjust outside for about a month before I
plant
them out.  It is OK if it is a bit chilly outside as long as they do not get
frost on them
or stay sopping wet. They do need to dry out some.  I have found that even
with a
covering over them, a frosty night can do some damage.  It won't kill them,
but can
burn the leaves.

     Germination in the refrigerator (vernalization) takes 12 weeks minimum.
To
calculate when you want to start the seed you need to figure the 3 months
growing
indoors, the 1 month hardening off outside and the 12 weeks in the
refridgerator.  For
me that is sometime in mid to late October.

I will now explain the germination process.  I take the bagged seeds in the
container
out of the fridge and make sure the bags are SEALED (yellow and blue makes
green,
right).  I make a 10% solution of bleach and tap water.  You can add a tiny
bit of dish
soap as this helps the solution cover the seed better, but this isn't really
necessary
unless you had seed that had a lot of mold growing on them.  I pour the bleach
solution into the container, close it up and shake gently to work the solution
into the
sealed bags (remember the holes in the bags?).  I then let it stand for at
least 30 mins
 to an hour.  CHECK TO MAKE SURE THAT NONE OF THE SEEDS HAVE
MANAGED TO ESCAPE OUTSIDE OF THE BAGS. Then I dump the solution out
and fill it up with fresh tap water, shake and let stand for 30 mins again.
Do this two
more times.  You are trying to make sure that all the bleach has been leached
out
 if all the crevices and places it had soaked into on the seed coat.   I let
the seed
drain the last time and then pour about a half cup of fresh water into the
conatiner
 with the seed and place in the fridge in some out-of-the-way place, but
easily
accesible.  This is the water that the seed will imbibe over the next few days
and
allow it to start vernalization.  Vernalization ( I'm guessing) can only start
when the
seed has been fully hydrated.

     Basically, now all you need to do is wait for twelve weeks.  Mark it on a
calendar,
or the container, when you put them in and when the twelve weeks is up.
Another
step that I think helps is once a month over that twelve weeks I take the
container
out and fill it up with water and let it sit for about 30 minutes and dump the
water out.
This may allow any germination inhibitors to leach out as they would outside
in the
rain.

When that twelve weeks is up I start checking the bags for germination.  This
is easy
 to do as the seed is dark, the bags are clear and the emerging roots are
white. After
 you have see enough seeds of a particular cross germinated or if some roots
have
gotten a bit too long remove the germinated ones and plant them in small pots.
I
plant each seed about 1/2" apart in a pot labelled with that cross and keep on
gradually spacing the seeds out in the pot untill it is filled.  If there are
more seeds
that germinate than a pot can hold I'll start a new pot until that one is also
filled.

I continue to do this untill the germination rate of each bag starts to
decrease
significantly.  This is when I start doing a temperature cycling process where
I
alternate the temperature between the refrigerator (35-38 F) and room
temperature
(70-85 F).  This simulates the day/night cycling outdoors in the Spring and it
has
worked well for me.   I would avoid putting them in a area of your fridge
where the
seed might freeze or make sure the general temp is not set to low as this may
damage the seeds at this point.  I get many more seed to germinate after the
germination has slowed down from the vernalization alone.  This process has
been documented in "Seed Germination Theory and Practice", Second Edition, by
Norman C. Deno.  It's a great reference for germinating almost any kind of
seed.
It is not readily available that I know of, but I can tell people where to get
it if
interested and it is still available.  Then again if you just want me to look
something
up real quick and not buy the book, I can do that too.  The cycling process
scheme
I use is like this.  I bring the container out of the fridge and let it stand
at room
temperature for at least 24 hours.  Next I check each bag for germination the
next
day and place those that have in their appropriate pot with the others of the
same
cross.  You could start a whole new pot if you want, as long as it's labelled
and then
can be reunited with the others later.  I then put the bags and container back
into
the fridge for at least 48 hours.  This allows them time to cool down and
cycle
properly.  Then I pull them out for another 24 hours at room temperature.  I
continue
to alternate between the two temps until germination has ceased or it is just
not
worth doing any more cyclcing as you may only be getting one seed every time
you do cycle, if that.

At this point I have to decide what I want to do with the remaining seed.  You
will
have some left, I always do but not always every cross.  Some have all their
seeds
germinated, some none at all.  I can either plant them out in pots to brave
the
weather outside, dry them down and and vernalize again next year and do the
who process again, or I can froce them to germinate by cutting the micropyle
end of
the seed to expose the root cap.  Cutting the seed in this way removes enough
of
the germination inhibitor to allow the embryo to germinate.  It is risky
though as once
the seed is cut it has to germinate or it is no good anymore.  Also, if the
embryo
gets damaged or its microscopic connection witht he endosperm gets diconnected
during the cutting it will not grow and die.

     I usually decide to cut the seed as this allow the whole cross to
continue and
grow with the rest of it's siblings.  If you have never done this before I
would suggest
practicing on a few seed (30 or so) untill you get the hang of it.  If you can
make
some crosses of something you know you don't really want you can waste these
seeds on your practice.  Also, don't just throw these seeds away.  Go ahead
and
plant them in some pots and see how they grow for you.  If the root cap gets
damaged
then they might not grow well, if at all.  It takes some practice, a keen eye
and steady
hand.  Hopefully you will see some abnormal shaped seeds and will give you a
better
idea of how to find the embryo in these.  I have found that usually the TB's
tend to have
the most odd-shaped or malformed seeds.  The technique works on 1/2 arilbreds
as
well.  I tried it on some pumillas and SDB's once but didn't get much, but
that was just
one cross of each and that is not a experiment or even conclusive.  I have had
whole
TB crosses that I had decided to use the cutting method on and still nothing
grew.  The
cut seeds just rotted.

After the seeds have been cut they need to placed in a wet towel until you
plant them,
hopefully very soon.  Do not plan to do this when you do not have the time or
are in a
hurry.  Once a cross has been finished cutting carefully and gently place the
seeds r
oot end down in CLEAN potting soil, cover with about 1/2" soil and apply a
fungicide
solution such as Captan or Dithane M-45 which is a bactericide/fungicide
(recommended).
Cover with plastic or a Growdome and place under the lights.  The soil I use
is MiracleGro potting mix.  It doesn't compact easily and doesn't stay too
wet.   I would stay away from
the sandy or vermiculite based types because they comapct easily, or those
with a lot of
perlite as these can get too dry on the surface while the seeds are sending
out roots and
won't form a good soil surface around the seed.  Also, if the soil is not
heavy or dense
enough the emerging root will tend to push the seed up out of the soil and you
will be
constantly replanting them if they haven't dried out.  The leaves should pop
up above the
soil surface in a few days if they are growing properly.  If they haven't done
anything in
about two weeks they probably won't and it's a lost cause.   Do your best to
control
fungus gnats as they will feed voraciously on the velnerable cut endosperm and
embryos.

Now that all the seed are growing in their pots under my flourescent lights I
let them
get to at least four true leaves and about 4" high, TB's, MTB's, IB's and
diploids.  Try
to let the the soil dry out some as this will promote the plants to produce
more roots
and control fungus gnats which will eat the roots of the young and older
seedlings.
This will take about 2 1/2 -3 months. Other types will usually be a little
shorter relative
to their types and may take a little while longer to get to an appropriate
size.  Then I
gently remove the plants from the pots and plant them individually into the
cells of the
bedding flat cell-packs.  I put them back under the lights for about a week to
2 weeks
to adjust and settle.  They can then go outside to acclimate to the sun and
weather before
they go into the garden.

This method works for me because I can monitor the whole germination and
raising
process to ensure that I get the maximum potential out of a particular cross.
If one cross
didn't make it, it wasn't due to bad weather, washing away of seed, seed being
eaten, overwatering, underwatering, pathogens, or the seed just not
germinating that year.  It also
lets me know that if a cross is worth repeating for it's ease of germination
or how many
more crosses of it to do if not that many grew to strat with.  I can then do
it again that
next Spring.  They bloom sooner in general, as stated earlier, and can
evaluate the quality
of the cross as a whole faster and repeat it sooner if I want to, or do sib
crosses sooner if
that was the goal to start with.  Some do like to germinate their seeds in
bags of potting
soil or vermiculite, or other potting component, in the fridge.  That is fine,
but my method
shows that there is no need for the soil or the clutter and mess occupying
your kitchen
(or your garden) and simply occupies the space of a mason jar or Tupperware
container
on a shelf at the back of the fridge.

It migth be simpler and agreeable for most people to vernalize the seeds for
twelve weeks,
pot them up as a whole batch and place them outside and let nature do her
work. The vernalization in the refridgerator is based on your planting
schedule and giving them an
earlier start might be an asset to those interested and could still give the
benefit of some
blooms by the next Spring.  Athough, without going through and doing the
special
treatment of cutting the non-germinators I do feel that you will get about
10-25% fewer
seedlings to grow and evaluate.  Don't forget it only takes one good one
better than the
rest.  I will note that I have not kept any record of whether a seed that has
been cut has
grown any better, or produced a plant any better, than one that germinated on
cue after vernalization or after temperature cycling.  That might make an
interesting experiment
for someone.

Paul Archer
Raleigh, NC  Zone 7



Original Merssage:----------

Paul,

I don't know about Adam or the rest of the list, but I'd like to hear more
about the details you left out.  I have some TB seeds and any tips you can
share would be appreciated.  This will be my first attempt at growing iris
from seed.

Kathy

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