Dr. Deno’s Seed Germination Books are now in Public Domain.

Wanaque, NJ(Zone 6b)

Over at the Seed Germination Forum it was announced that “Dr. Deno's books are now in the public domain”. Read this great post in full:
http://davesgarden.com/community/forums/t/1134402/

You can use these persistent links to directly access the USDA website which contain the Deno Books in PDF format.

Seed Germination: Theory and Practice
http://hdl.handle.net/10113/41278

First Supplement to Seed Germination: Theory and Practice
http://hdl.handle.net/10113/41279

Second Supplement to Seed Germination: Theory and Practice
http://hdl.handle.net/10113/41277

The documents in the USDA website support OCR-to-Text so you will be able to search the books using key words and cut and past text to DG posts. Download the books to your computer and keep them as a reference source.

I now start all my Hibiscus seeds using the Demo Method. The only problem with the Demo Method is that it works too well and little Hibiscus seedlings quickly become big Hibiscus seedlings. With seed nicking and a 24 hour soak in warm water, germination times are typically under three days.

Mike

(Karen) Frankston, TX(Zone 8a)

Mike what is the Demo method please?

Wanaque, NJ(Zone 6b)

The Deno Method is a process by which you germinate seeds on damp kitchen paper towels inside a Ziploc plastic bag. DG member “Blomma” has a number of excellent posts with pictures on the Deno Method. Here are a few links in the Hibiscus Forum.

http://davesgarden.com/community/forums/t/1080410
http://davesgarden.com/community/forums/t/1047978

With Blomma's help, my Hibiscus seed germination success rate went from under 50% to nearly 100% after I switched to the Deno Method. By starting the Hibiscus seeds on kitchen paper towels you can select the most healthy seeds for transfer to the starting trays. Also, you don't waist valuable growing space planting dead seed. In New Jersey, the seeds of some of the Hibiscus I grow and all of the seeds I collect in the wild are at risk from the Hibiscus beetle Althaeus hibisci, so eliminating dead or compromised seeds is a big advantage for me.

Here are the things which I have found to be important:

1. Nick your Hibiscus seeds but be careful with the seeds and don't nick yourself.
2. The Hibiscus seed must be nicked on the side of the seed opposite to where it was connected to the pod.
3. Use heavy-duty Ziploc bags but don't waist your money on the fancy Slider locks.
4. How you fold the kitchen paper towels is not that important but you want four ply of damp paper towels above and below the seeds.
5. As I am germinating a lot of seeds, I generally use two sheets or paper towels to form the four layers but for small batches one sheet will work.
6. Do maintain an air bubble inside the Ziploc plastic bag, it is tricky the first few times so practice.
7. Any cable or satellite receiver makes a good heat pad but I put the bags in a small aluminum try to distribute the warmth and keep water out of the electronics.

Read all of Blomma's posts for the details. Here is another link which will be of use when starting small seeds.
http://www.robsplants.com/seed/baggy.php

Mike

This message was edited Oct 29, 2010 9:01 AM

Wanaque, NJ(Zone 6b)

I just had an idea!

Let's send thank-you cards (something with flowers) to Dr. Demo for placing his books in the public domain. His mailing address is as follows.

Dr. Norman C. Deno
139 Lenor Drive
State College, PA 16801 USA

All DG Forums should be interested in this so please get the word out.

Mike

(Karen) Frankston, TX(Zone 8a)

Thank you so much Mike!

Ventress, LA(Zone 8b)

Well, this is good to hear. I bought 20 seeds from the Intl Hibiscus Society. I planted them over a month ago, went thru nicking the seeds, etc. Only 1 has shown green for a week and a half, but won't come completely out of the soil.
Your method is worth a try. I did not use the damp paper towel. I went directly to damp soil.

Another DGer was gracious enough to send me seeds, but I wanted to find out what I did wrong before planting any more.

Wanaque, NJ(Zone 6b)

A week ago Saturday October 30, 2010, I collected over a thousand seeds of what may be a color variant of a wild Hibiscus moscheutos from what reports to be an early 1900’s marshland restoration area in the New Jersey Meadowlands. Over 75% of the seeds were compromised the Hibiscus Seed Beetle (Althaeus hibisci). The Hibiscus Beetles was very active in the collected seeds, many seeds had visible holes from which the Beetles had hatched and many seeds were suspected of containing un-hatched Hibiscus Beetles because of appearance. Using the water flotation technique which I have discussed elsewhere in DG, I isolated several hundred Hibiscus moscheutos seeds which I believed to be sound because they floated for extended periods of time without any visible swelling.

I randomly selected two batches of ten seeds each, of the good seeds, and nicked one batch and not the other. I put both batches of seeds in hand-warm for 24 hours. The nicked seeds all sank within 4 hours and began to swell in size while the un-nicked seeds continued to float. Both batches were transferred to heavy-duty Ziploc bags with four-ply of moist paper towels above and below the seeds. The Ziploc bags were placed on my television receiver unit to provide warmth.

Within three days, nine of the ten nicked seeds had broken dormancy and had grown to over one inch in length or longer and were transferred to soil in starter trays. Two of the nine seedlings were noticeable weaker than the other seven but growing. Using seed nicking with the Deno Method allows you to visibly inspect Hibiscus seedlings before you transfer them to soil to grow. I suspect the seed nicking combined with the Deno Method is a form of embryo rescue were seeds which would not have survived under natural conditions can successfully germinate. If your objective is to reestablish a wild population this may not be viable long term strategy but it will allow you to jump start a new generation for reintroduction into the wild. For a domestic cultivar, which will be propagated using vegetative methods, seed nicking and the Deno Method allows you to inspect every potential seedling for desirable traits.

For the ten un-nicked seeds, only one has broken dormancy and has a half inch root after five days in the Ziploc bag. I should mention that wild Hibiscus moscheutos seeds are significantly smaller than the hardy Hibiscus cultivar under domestication. Fortunately the seeds I collected last Saturday October 30, 2010 are small, as a wild Hibiscus moscheutos seed should be. Here is a picture of specimens I hope I collected. This pink color morph with no red-eye will occur in nature but it is unusual. I will know next year if I collected the correct seeds. The photograph of the leaves is consistent for a wild Hibiscus moscheutos,
http://www.flickr.com/photos/61897811@N00/47282403

The Deno Method combined with seed nicking has allowed me to do the following.

1. Verify the success of separating Beetle compromised Hibiscus moscheutos seeds with nearly 100% accuracy without the use of any chemicals.
2. Prevent the distribution of the Althaeus hibisci Beetle in seeds trades.
3. Verify that the germination success rate of the good seeds is 90%.
4. Germinate both strong and weak Hibiscus seeds.
5. Start a new crop of Hibiscus moscheutos seedlings in less than a week from the time of collection in the wild.
6. Transfer only germinated seedling to the starter trays which saves space.


Mike
Attachment: Picture of my nine Hibiscus moscheutos seedlings as of Sunday November 7, 2010.


Thumbnail by Michael_Ronayne
Ventress, LA(Zone 8b)

Thanks Mike. If at first you don't succeed, try try try again.

cullman, AL(Zone 7b)

I hate those beetles thankfully they only got one of my seed pods this year...

Wanaque, NJ(Zone 6b)

In the version of the Deno Method which I use, two sheets of white kitchen paper towels are separated and each is followed twice forming a square of approximately 6”x6” with four ply of paper in each square. The two squares are hydrated with water but not excessively, opened and interleaved forming a 6”x6” square with two flaps of each side. Previously treated seeds are placed in the center and the two flaps are closed reforming the 6”x6” square with four-ply of hydrated paper above and below the seeds.

I had been using an inflated Ziploc Bag to maintain moisture during the germination; but, recently found that the Slider Ziploc Bag is more effective at remaining inflated for days during the germination process.

There are problems with this technique:

1. Small seeds can get trapped in the holes in the paper towels.
2. Seeds with fast growing root hairs can become entangled in the paper towels.
3. Root entanglement is a problem for seedlings which are slow to separate from the shell.

Once root hairs are attached to the paper towels it is very dangerous to try and separate the root from the paper. In such cases, it is better to cut the paper away and plant the seedling with a piece of paper attached.

In discussing this problem with DG member Htop from San Antonio, who was using the Deno Method for the first time I had speculated that a layer of writing paper might mitigate the above problems but I know that such paper has been treated with whitening agents to improve contrast and would not be rated as food-safe. Kitchen paper towels are intended to come in contact with foods and should be safe. Htop suggested that Parchment Paper (http://en.wikipedia.org/wiki/Parchment_paper_%28baking%29 ), also know as Baking Paper, was food-safe and might be just the thing I was looking for. It turned out that there was already a ready supply of parchment paper in my kitchen which I was able to use for testing.

Parchment paper is dense and at first repels water. I found that if I boiled the parchment paper in water for a few minutes, over the stove or in the microwave, it becomes hydrated and will remain so as long as it isn’t allowed dry out. I have stored hydrated parchment paper in water for days in anticipation of future use. Pleased be careful when working with any boiling liquid!

When I am ready to start seeds, I cut a 6”x12” section of parchment paper which is first hydrated in boiling water. The parchment paper is folded into a 6”x6” square which is placed in the open square of folded kitchen paper towels. The seeds are placed on the parchment paper and the second section of parchment paper is folded over the first inclosing the seeds. The two flaps of the kitchen paper towels are then folded enclosing the parchment paper and seeds. The resulting 6”x6” square of hydrated paper consists of four ply of kitchen paper towels and one ply of parchment paper on top, a layer of seeds and one ply of parchment paper and four ply of kitchen towels on the bottom. The paper sandwich with seeds goes into a Slider Ziploc Bag when root development starts in one to two days. I use to move the seedlings to dirt once there was good root development but now I try and wait until the seedling has seed-leaves and has separated from its shell.

I move the seedlings to dirt one at a time as I judge them to be ready. Generally, the transfer process can extend over a number of days and the healthier and vigorous seedlings are the first to be moved and can retain a growth advantage for months.

Attached is a picture of hybrid Hibiscus seedlings after two and a half days in the Deno bag. There seeds were nicked and hydrated for 12 hours in hand-hot water. The seeds are the result of a cross between Hibiscus Moy Grande (pollen) and Hibiscus Lord Baltimore (pod). This the second batch of this cross, germinated using a layer of parchment paper and I have not observed any tendency for the root hairs to stick to the parchment paper. Thanks to the kitchen paper towels the parchment paper remains hydrated and able to deliver water to the seeds. Hibiscus seeds have a tendency to easily role on parchment paper so be carful to work on a flat surface. I have not tested this technique on small seeds as yet. When you hydrate the kitchen paper towels, remember that you are not doing a TV commercial, you don’t want the paper sopping wet.

Mike

Thumbnail by Michael_Ronayne
Ventress, LA(Zone 8b)

Thanks Mike for reminding us of this method. If I don't write it down, it doesn't get done.

Wanaque, NJ(Zone 6b)

Attached is a picture of my hybrid Hibiscus seedlings after three and a half days in the Deno bag and resting parchment paper which is covered with a thin film of water. There is absolutely no tendency for the root hairs to become entangled in the parchment paper, which continues to deliver adequate hydration to growing seedlings. The seedlings can be easily lifted off the parchment paper by hand, if you are carful. Many of these seedlings are now well past the time when I would normally transplant them to dirt. I will most likely transplant the seeds later today.

Mike

Thumbnail by Michael_Ronayne
Wanaque, NJ(Zone 6b)

The use of a layer of parchment paper to separate the Hibiscus seedling from the paper towels has been successful beyond my wildest expectations. Attached is a picture of the hybrid Hibiscus seedlings at five and a half days. Starting with 20 seeds, 8 seedlings had well developed root systems of approximately 2 inches in length and were transferred to dirt in pots. 2 seedlings had separated from their shells and need some more time to grow in the Deno Bag. The last 2 seedlings had not as yet separated from their shells and their long-term viability is still known. Out of 20 seeds, 12 seeds or 60% germinated while 8 seeds failed. Given that these seedlings are descended from 5 unique Hibiscus species, the germination rate is quite good.

Even after five and a half days, there is absolutely no tendency for the roots to stick go the parchment paper. I easily picked up the very healthy seedlings between my fingers and transfer them to their new pots without incident. A small spatula or plastic knife would have worked equally as well. In mid August I will be germinating small Dianthus seeds using the same method.

Mike

Thumbnail by Michael_Ronayne
San Antonio, TX(Zone 8b)

I'm so happy that the parchment paper solved the problem with the root hairs becoming entangled in the paper towels. Thanks for posting the photos with descriptions of when you transfer the seedlings to dirt ... very helpful to those of us who are new at this. :o)

Wanaque, NJ(Zone 6b)

Attached is the photograph of the 4 remaining seedlings after 8 days in the Deno Bag. These seedlings have been growing but they are not nearly as healthy in appearance as the first 8 seedlings which were planted on day 4. There is absolutely no tendency for the root hairs to become entangled in the parchment paper. One of the big advantages of the Deno Method is that the seedlings can be evaluated and categorized before planting in dirt. In total, I planted 12 hybrid Hibiscus seedlings out of 20 seeds which were stared. 8 seedlings were judged to be vigorous, 2 were reasonably healthy and 2 were marginal and may not survive. I will post an update in a few weeks.

After the last seedlings were planted, I washed off the parchment paper which cleaned easily. In about 12 hours the parchment paper had returned to nearly its original state with a little bit of crinkling and discoloration in the paper.

I have been thinking about using a Deno Bag to ship seedlings. The seedlings would be started in one Deno Bag and then the growing seedlings would be transferred to a new Deno Bag for shipment through the mails. I need to develop a supporting frame to keep the paper layers from becoming entangled during shipment and have some ideas in that direction but additional work required.

Mike

Thumbnail by Michael_Ronayne
San Antonio, TX(Zone 8b)

Using a Deno Bag to ship seedlings is a great idea.

Brooksville, FL(Zone 9a)

Mike

Very interesting trials here. I do have a question, you stated that you leave sprouted seedlings until leaf development. What keeps the leaf from rotting? Is it the parchment paper, as in the past when I've started seeds this way (was in paper towel) if I forgot to check and leaf developed to only rot.

Thank you again for posting your results.

Jan

Wanaque, NJ(Zone 6b)

From: "meadowyck"
Very interesting trials here. I do have a question, you stated that you leave sprouted seedlings until leaf development. What keeps the leaf from rotting? Is it the parchment paper, as in the past when I've started seeds this way (was in paper towel) if I forgot to check and leaf developed to only rot.

The amount of water inside the Slider Ziploc page is small and it is critical that the bag remain inflated. After I hydrate the paper towels, I give them a gentle squeeze to remove excess water. You want to create a condition similar to a rainy day. If a layer of parchment paper is used, there is even less direct contact with water. Capillary action is delivering water to the growing seedling and the leafs are never really that wet. Using a quality Ziploc bag, which remains inflated for a week, greatly reduces the chances of the growing leafs being damaged. If you open the bag to inspect the seedlings, be sure to re-inflate the bag as you are closing it. I start transferring the seedlings to dirt by day 5 and much past day 7 I become concerned.

This message was edited Oct 7, 2014 2:27 AM

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