| I've never tried ga3 but here is an article found on the web about use of ga3 for violet seeds.. 1
BULLETIN OF THE ALPINE GARDE~ SOCIETY
VIOLET dERMINATION
Kim Blaxland discusses the germination of the seeds of Viola species
ln the article 'Doubts and DifficuIties' (Bulletin 63: 100, 1995) therê .:.vasa question from
Mrs A. M. (Betchworth, Surrey) askingt.about the sowing techniques required for Viola
species. As the Panel of Experts were able to offer only a litde help, l felt that l should
share my experiences and methods for germinating these seeds.
Firstly, it is important to examine thé seeds with a magnifying glass to see ifthey are
intact. Viola seeds sent through the mailtare nearly always squashed by the mail sorting
machines, so it is important to wrap the seeds in bubble plastic before mailing. Damaged
seeds.will not germinate. Nearly aIl the' viola seed that l was allocated from the AGS
Exchange in 1994 and about half of thatlfor 1995 arrived squashed.
l have always believed that the best way to germinate seed is to copy what the plant
does in nature, viz. to sow the seed in the summer to autumn period, on the top of the soil,
and let nature do the rest. For violas the r~sults of this approach pro duce some seedlings
but l am always disappointed that so few'species grow.
. For the past two years l have used a method of treatment to encourage germination
described by Norman Deno in an article he wrote for the NARGS Bulletin (SI (1), 1993).
To be safe, l divided the contents of eachlseed packet in two, retained one halffor treatment
and sowed the other as l had always previously done, in a potting mix and placed
the pots outside for the winter. The retained seeds were sprinkled with gibberellic acid-3
powder (GA-3) on a numbered square of clamp paper towel, the towel was folded, placed
in a plastic bag (as many as will fit in the same bag), sealed and stored in the refrigerator.
Every two weeks each packet was opened and the seeds checked with a magnifying
glass for any germination. Germination started about four to six weeks after treatment
.- and coritinued for more than six months. Ally germinating seeds were picked out with
tweezers and potted up and the packets of ungerminated seeds were replaced in the refrigerator.
The§ame potting mix was used for each method.
Germination of the treated seeds in the refrigerator has been much greater than for the
untreated seeds in pots outside. For some species l have tried both treated and untreated
seed in the refrigerator in separate plastic b~gs and in each case the number of germinated
seed was far greater for the treated seed. This year 86 out of 109 packets of treated seed
have germinated, with at least one seedling per batch, while most had several to many.
The improvement in germination rates has been so great that l have decided from now on
that l will only germinate viola seeds by ~A-3 treatment and not bother with my old
method, with a few exceptions.
Seeds from most of the pansy type violets (W. aetolica, dubyana, calcarata, tricolor,
stojanowii) will usually germinate quite readily without any special treatment. If these
species are treated with GA-3 the resulting;seedlings will become far too etiolated and
weak and may die off. This could also mean that the concentration of GA-3 that l am
giving them is too strong. ln future l will tryJl.lsinga smaller dose, especially for aIl small
seeds. If germinating seedlings are left in t~e refrigerator for too long they too will bel
OPPOSITE: Viola ~fllcarata iD the wild Photo: Muriel Hodgman
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1 BULLETIN OF THE ALPINE GARDEN
! :SOCIETY
corne etiolated, because they are still gr wing under the influence of GA-3. l have tried
sprinkling the GA-3 powder directly onto the top of pots of ungerminated seeds. This
produced some results as weil but as l &idnot run a control at the same time, l cannot
prove that my treatment was the cause
1 germination. This method may also encourage
the seedlings to become etiolated if thGA-3 remains in the soil. l am reminded of a
similar methodrecommended by Josef aida for treating seed with hydrogen peroxide,
of the strengthused for bleaching hair. .esaid that the seeds will germinate before your
eyes, but must be washed immediately!in fresh cold water to stôp them growing too
quickly! l would only try this method o~expendable seed.
l have treated rosulate Viola seed wifhGA-3, producing 100%germination in some
species, but when the seeds were potteii up they continued growing at a rapid pace. l
have since been able to slow the growtThin some of the species by severely restricting
moisture, keeping the plants cool and growing them under strong grow lights. Others
just kept on upwards to more than 151m. Obviously it would be worth trying lower
doses on aIl the rosulate species. 1 Seeds of an annual rosulate violet ge
~ inated prolifically without any treatment, and
grew to their natural height under grow Ii' hts with restricted moisture. Some treated with
GA~3 became very etiolated and did not thrive like the untreated ones. Next spring l am
going to try growing the annual species n the open garden. .
This year l have potted aIl the treatedlseeds which are still ungerminated at the end of
six months. ln one pot a seedling has erberged but in future, experiments will be done
with different lengths of refrigeration tirpe followed by subsequent potting on.
Seeds from plants which grow in cliljnates where the temperatures do not fall below
freezing should not be placed in the refriperator, e.g. W. amiana, hederacea (except the
alpine subsp.fuscoviolacea if seed is ever available), tashiroi and diffusa subsp. apoensis.
The GA-3 treatment can be used adany time of the year, whenever seed becomes
available. l have successfully potted up ~erminating seeds in the heat of summer (3Y C),
placing the pots in shade and giving them constant moisture. Some seeds germinated last
year in early winter, so the pots were ke~t indoors under lights for the winter. The plants
grew weIl and produced cleistogamous pods and seeds but did not flower this spring.
For the collectors who contribute seed, care must be taken to collect mature seed.
Viola seed pods are usually carried hanglng downwards while they develop. A few days
before they are mature the pods start to tum upwards and when they are erect they will
usuallyopen within 24 hours. This is the,ltime to collect, preferably early in the moming,
before the pods have time to open. \
From my own experience, seeds remain viable for more than one year. l have had
success this year with a packet of seed ~f V. schariensis collected in September 1993.
Without any treatment seed may take more than one year to germinate (e.g. V.
tokubuchiana).ln my garden seed often ferminates a few years after the parent plant has
disappeared, which would be a natural protection for the survival of species. l store the
seed at room temperature, in paper enyelopes. l have no evidence that this treatment
reduces viability. Seeds that fail to germInate are usually either immature or damaged.
l must stress that this method of ge
~ ' inating seeds is very simple and easy. GA-3
should be available from a chemical sup Iy company. The smallest amount that l could
buy was 5 grammes for the cost of abo t $US 70. The chemical does not deteriorate
when kept in a screwtop botde. This ampunt williast one pers on for years, or could be
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Viola tricolor ln the Auvergne, France
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Photo: C. Grey-Wilson
divided among several people. ln the US chemical companies may have some restrictions
on selling to individu ais but are happy to sell ta a business, nursery or association.
Here are a few practical points for those who decide to give it a try. 1cut each sheet of
paper towel in half, number the paper in the top right corner with a waterproof pen, then
keep a record in a book. However, it would be simpler ta write the species' name on each
sheet. Turn the paper over so the number or name is on the outside of the final folded
packet. Dampen the paper by pouring a few draps of water in the middle, but do not
saturate. Too much moisture will encourage the growth of mould. Insert the tip of a dry
toothpick about 5 mm into the GA-3 and pick up the amount ofpowderthat sticks to the
toothpick. Sprinkle this onto the centre of the paper and if necessary spread it out evenl y.
Place the seeds in the centre spreading them out weIl so they are separate. If the seeds
group together mould may spread. Do not put too many seeds on one sheet for the same
reason. Try not to put any damaged seeds or parts of seeds onto the paper because they
will be the first to attract mould. Mould will develop on some of the seeds, which must
also happen in the soi!. Many seeds germinate when they have already bec orne mouldy
so do not throw them out too soon, but not aIl seeds will grow mou Id. Fold the right then
the left sides of the paper over the middle, so that the number or name is now on the top
right of the front. Fold the bottom third of the paper upwards, and the top third backwards
and down, so that the small packet now has the seeds in the middle, with several
layers of paper on each side. When the packets are sealed in a plastic bag, do not leave a
lot of air inside, because the moisture from the dampened paper will condense on the
inside of the plastic bag at the top and the paper towels will dry out too much. Some
brands of paper towel tend to disintegrate with constant folding and unfolding: if sa
change brand!
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