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We received this from Fred Bergman and are posting it here with
our thanks to him. We hope you'll find it useful!

From Seed Sowing, the easy way, 1996. Orchid Review, 104:23-25.

A note to me from Fred....
The best general purpose media I have found is Hill's Seed Sowing 
Medium available from 
G & S Laboratories 
645 Stoddard Lane 
Santa Barbara CA 93108.

An amateur bottle makes l Liter, costs $ 6.50pp. Ca residence add 7.75%.
Supplies are available from almost any chemical supply house, one being
the Aldrich Chemical Company Phone 1-800-558-9160, Fax 414-273-4979.
They accept credit cards. They have Erlenmeyer flasks, 500 ml, Z14,053-8
at 4.15 ea or 6/22.95; rubber stoppers, size 7, Z16,437-2, 20/16.75; 
plastic sample vials with caps, 1.85 ml, Z13,618-2, 12/9.95; or glass vials 
with caps, 2 ml, Z29,169-2, 100/29.00; and pH paper, Z11,181-3, 6.00/pkg.
Calcium hypochlorite can be obtained form a swimming pool supplier; copper
sulfate from a garden center, and demineralized water at almost any 
supermarket. Desicant packets can usually be obtained at no charge from 
your nearest pharmacy.Total cost  about $70. I was off a little.

Tyndallization may be used to sterlize your media if a pressure cooker is
not available. However a pressure cooker is more convient and reliable.
Tyndallization consists of steaming 3 to 4 times at 24 hr intervals. Room
temperature is maintained between steaming intervals. Use a covered kettle
provided with a wire rack that suspends the flasks over the boiling water.
Boiling should continue until the contents reach the boiling point and is
maintained for a few miniutes.
Many orchid enthusiasts have been told that the 
germination of orchid seed requires special skills and 
equipment. This is no longer true. Recent developments 
have made it possible for anyone to successfully sow seed. 
The only special equipment required is a large pressure 
cooker normally used for canning.                           
During a study of seed disinfection, I discovered that it 
is possible to add disinfection solution and seed directly 
to the flasks. Good germination is obtained when the 
following conditions are met; use only calcium 
hypochlorite (CaHc), use CaHc at a very low concentration 
and a low pH, and remove the CaHc solution from the flask 
after the seeds have settled to the surface of the media. 
I also found that flasks could be safely opened for seed 
sowing by working under a cloth towel moistened with 10% 
liquid bleach. These two techniques were combined and 
tested repeatedly, producing viable cultures free from 
contamination. The sowings were made in an area attached 
to a greenhouse where plants and blooms are normally 
packed for shipment. This area, far from a clean room, 
demonstrated the effectiveness of this novel approach.      
Over the years I have avoided reflasking, a task I do not 
enjoy, by adopting the technique of sowing seed thinly and 
restricting the loss of moisture from the media. This 
approach makes it is possible to produce husky plants 
without reflasking. By combining this novel seed sowing 
technique and eliminating reflasking, it is possible to 
sow seed successfully without the use of an enclosure or a 
laminar-flow hood.
This paper provides a description of the entire seed 
sowing procedure so that the novice will not have to 
search the literature for supporting information. Many of 
the required supplies are already available in your home. 
The following is a list of the special supplies you will 
need to acquire.
1-Calcium hypochlorite (CaHc)
2-Six 500 milliliter Erlenmeyer flasks                      
3-Six one-hole rubber stoppers to fit flask
4-Copper sulfate
5-pH meter or pH paper to cover the 5 to 6 range
6-Dehydrated orchid media for one liter of solution
7-Six small bottles with caps, 3-5 milliliter capacity
8-Three liters of demineralized water
Seed sowing starts with the proper harvesting of seed. 
When a capsule starts to change color, began checking the 
capsule on a daily basis. When a crack first appears, 
remove the capsule and split the capsule lengthwise. Place 
the capsule on a sheet of writing paper and cover the seed 
and capsule with a second sheet of paper. After 24 hours 
the seed can be shaken from the capsule. The seed, if 
viable, will be free flowing and light yellow to brown in 
color. After separating the seed from the capsule, store 
the seed in a folded section of writing paper. If the seed 
will not be sown for several weeks, place the seed packet 
and a desiccant packet in a small closed container. Store 
the container in the vegetable crisper of your 
refrigerator. When you are ready to sow the seed, remove 
the container from the refrigerator and allow it to warm 
to room temperature before opening.                         
There are four operations that can be performed ahead of 
time: (1) locate a jar with a plastic cap that holds about 
250 milliliters (one half cup) and add about 30 grams       
(2 tablespoons) of copper sulfate. Fill the jar almost 
full with water and shake the solution occasionally until 
all the copper sulfate has dissolved, (2) pack the hole in 
each rubber stopper with adsorbent cotton, (3) cut twelve, 
12 centimeter squares of aluminum foil, and (4) prepare a 
stock solution of (CaHc).                                   
You must determine how much CaHc powder will be required 
to prepare the CaHc stock solution. This is done by 
dividing 2.0 by the percent of available chlorine in the 
CaHc. This will give you the number of grams of CaHc 
required for 1 liter of stock solution containing 2000 ppm 
as available chlorine (AC). For example, if the CaHc 
contains 65% AC, (sometimes listed as the active 
ingredient) divide 2.0 by 0.65 to find that 3.08 g of CaHc 
should be dissolved in 1 liter of demineralized water. If 
you prefer to use non metric units and/or you do not have 
a sensitive balance, use the following procedure. The 
weight of a level one quarter teaspoon of CaHc is close to 
0.85 g. Multiply 0.85 by 1000 and divide by 3.08 (the 
weight of CaHc determined following the above example). 
The result is 276, which is the milliliters of water to be 
used with one quarter teaspoon of CaHc to produce a 2000 
ppm AC solution. Finally, divide 276 by 29 to find that 
276 milliliters is equal to 9.5 fluid ounces. Using 29 in 
the conversion of milliliters to fluid ounces produces a 
solution within 5% of the desired concentration using 
either British or US fluid ounces. Preparation of the 
solution consists of measuring the water, adding the CaHc, 
and stirring for several minutes. Allow the solution to 
stand for 10-15 minutes and filter the solution using 
either a rapid filter paper, like a #4 Whatman, or a 
coffee filter. Collect the solution in an amber glass 
bottle, or a bottle covered with aluminum foil, and store 
in the refrigerator. A stock solution prepared and stored 
following these directions will be good for at least a year.
When you are ready to sow your seed, prepare the media at 
least one day ahead. If you purchase dehydrated media for 
1 liter of solution (which is enough for 6 flasks), you 
will not have to weigh the media. Media preparation 
consists of pouring, while stirring, the dehydrated media 
into 1 liter of demineralized water contained in the top 
section of a double boiler. Add water to the bottom 
section of the double boiler, replace the top section 
containing the media, and bring the water in the bottom 
section to a gentle boil. Continue boiling for about 20 
minutes, or until the media has dissolved and is free of 
lumps. When completely dissolved, pour 160 milliliters of 
media into each 500 milliliter flask, using a funnel to 
prevent the media from contacting the neck of the flask. 
Stopper the flasks loosely with the rubber stoppers, cover 
the stopper and top of each flask with an aluminum foil 
square, and place the flasks in the pressure cooker. Heat 
and bring the pressure cooker up to 1 kg/cm (15 psi). 
Maintain the pressure for 30 minutes. The media requires 
several hours to gel, so after you discontinue heating, 
either move the cooker to where you will be sowing the 
seed while it is still quite warm or allow it to cool 
completely before moving.

When you are ready to sow the seed, add 5 milliliters (1 
teaspoon) of CaHc stock solution to 40 milliliters (8 
teaspoons) of demineralized water. Add white vinegar drop 
by drop until the pH is between 5 and 6 using a pH 
indicator. This final solution of disinfectant contains 
250 ppm (AC). Finally, add 1 or 2 drops of liquid 
detergent and set the disinfectant solution aside. Once 
the pH has been lowered the solution is only good for a 
short time. If you should you be interrupted for an hour 
or more, prepare a fresh solution.

The next step is to place the seed, equal in volume to a 
half grain of rice or less in one of the small (3-5 
milliliter) bottles. One bottle should be prepared for 
each flask you will sow. Set the bottles of seed aside and 
add 100 milliliters (one half cup) of liquid household 
bleach to 900 milliliters (4 and one half cups) of water 
in a wash pan or other shallow container. Add 10 
milliliters (2 teaspoons) of sodium bicarbonate to the 
bleach solution to make the solution easier on your skin. 
Put on a pair of disposable latex gloves and place 2 hand 
towels, of tightly woven material, in the wash pan. 
Submerge the towels in the bleach and wet the surface of 
the gloves with the bleach solution. Next, take the seed 
bottles and add the dilute CaHc solution (200 ppm of AC) 
to each bottle leaving a small air space at the top. 
Firmly cap each bottle after filling, and when all of the 
seed bottles are filled, shake the bottles briskly to wet 
the seed. Shake the bottles occasionally for the next 
10-15 minutes. While the seed is soaking, open a sheet of 
newspaper next to the pressure cooker and wash pan. Wring 
out the hand towels and spread them open on top of each 
other on the newspaper. Now drop the bottles containing 
the seed in the bleach in the wash pan. Release the lid on 
the pressure cooker, remove 1 flask, and set the cooker 
lid back on the cooker. Place the flask on the bottom 
towel and under the top towel so that the flask is 
completely covered. Rinse your gloves in the wash pan, and 
remove one of the seed bottles and place it under the 
towel next to the flask. Working under the towel, remove 
the aluminum foil cover and the rubber stopper from the 
flask, taking care to keep the stopper under the top 
towel. Give the seed bottle a shake and quickly remove the 
cap. Pour the seed and disinfectant into the flask and 
replace the rubber stopper. Leave the flask under the 
towel and wait 1 to 2 minutes. Still working under the 
towel, tilt the flask slowly on its side at the same time 
withdrawing the stopper sufficiently to allow the 
disinfecting solution to be poured from the flask. If you 
tilt the flask with a gentle movement, most of the seed 
will remain on the surface of the agar. Reseat the stopper 
and remove the flask from under the towel. Set the flask 
aside, remove the second flask from the pressure cooker 
and place it under the towel. Rinse your gloves in the 
wash pan and repeat the seed sowing process until all of 
the flasks have been sown. Don't forget to have a system 
to label each flask either before or after they are sown.

When all of the flasks have been sown, place one drop of 
copper sulfate solution on the cotton in the rubber 
stopper and one drop in the crack between the neck of the 
flask and the rubber stopper. Cover the stopper and the 
top of the flask with a fresh aluminum foil square and 
place the flask in a warm and bright location, but not 
direct sunlight. The final step is the hardest part of the 
procedure, waiting for the first signs of germination.
By following this simplified seed sowing procedure, even 
those without previous experience can achieve good 
results. If this is your first attempt at seed sowing, it 
would be a good idea to make a dry run using just the 
empty equipment before you try it with seed. Each 
operation is a critical so don't alter the procedure 
before giving any modification careful consideration. In 
addition remember that this is an alternate procedure, the 
preferred procedure remains removal of all disinfecting 
solution by filtration followed by several water rinses 
before the seed is added to the flask.                      
It is hoped that you will be encouraged to try sowing your 
own seed. From my own experience, I believe that there are 
few events in life that are more satisfying. Join me in 
watching your own seed turn green and grow into viable 

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