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The man behind freeze-Pruf, the "holy grail of horticulture"

by FigTree

Dr. David Francko the inventor of Freeze-Pruf
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A lot of scientific stuff has been published about Dr. David Francko the inventor of Freeze-Pruf, but let's get to know who this guy is and why he made this product!

Before I get into it, let's get these points of the way so as not to confuse anyone who might care:

  • I am not an expert on anything to do with science, in fact I think I successfully failed chemistry in high school.
  • I personally have not tried Freeze-Pruf yet, but you bet I will very soon as I have been wearing my down jacket inside for the past week here in Seattle.
  • This product is NON-TOXIC and environmentally friendly.  It has nothing to do with Anti-freeze like you put in your car.  It is made of NON-TOXIC materials.
  • This product is a ZONE EXTENDER, and adds a half USDA Zone equivalent to the cold tolerance range of all major ornamentals and crops. So a plant that's hardy to the low-to-mid teens Fahrenheit (Zone 8a) can be grown with little ot no damage in Zone 7b.  This does not mean that a person living in Boston can now grow Banana Trees in December.

After talking with Dr. Francko on the phone last week, I felt like I had just had a booster shot of good vibes. This is one busy guy, and talking on the phone with me seemed like the most important thing he had done all day- we talked science, academics, inspirations, and family- I could have talked to him for hours, and afterward I felt a little like I had spoken with a scientific Oprah.

Dr. Francko is of the spudnik generation, and in 50's and 60's there was a real push for kids to get into science.  He says he was an oddball kid whose parents recognized he was a little different.  But his parents also were incredibly supportive of his interests and talents, using the small resources they had to purchase science kits and helping him with his education- even letting him turn their backyard pool into a fish and tadpole microcosm.  Being the first generation in his family to go to college, he found even more support there from mentors.  And when he went on to get his masters and became a doctoral candidate, again he had teachers along the way helping and supporting his ideas.  So he is the first to be extremely supportive of young people,  "working as an administrator to mentor young people is so important.   Without it they can drift away".  He says that, "First generation kids need mentors.  It is so very important and I am proud that we do that at University of Alabama"

Dr. Francko is the Assistant vice president for academic affairs and Dean of the University of Alabama Graduate School (big title) and also has a little project on the side working in the lab of University of Alabama, and coming up with a product called Freeze-Pruf for the compnay Liquid Fence, a non-toxic spray for plants that is proving to be a true winner in the race against the cold.  Starting his research at the University of Miami, Dr. Francko worked with geneticists trying to find a way to help existing cultivars more tolerant of cold weather.  He looked at an array of species to see how they naturally tolerated and reacted cold.  He looked at amphibeans, insects, tissue cultures, even humans and tried to see what these natural reactions meant- could he somehow make the natural mechanisms that plants already have to tolerate cold, and take it a few steps further? 

The way Dr. Francko describes the way Freeze-Pruf works; "it dehydrates the cell so it doesn't harm the cells, we combined different parts and tried to fine tune them so that it doesn't avoid the freezing process it helps plants tolerate it and builds on what the plant already does naturally."  If you want to learn more about the science, read this from the Liquid Fence website, and this artcile from Science Daily- they sound like they know what they're talking about.

When asked about how this is going to be a part of what we're seeing in climate change Dr. Francko says, "this product designed to be an eco-friendly product.  Whatever degree climate is changing- we will have less resources and more people.  We must work more efficiently as this [Green revolution] is not a fad- this is the way things will be done in the future.  Kids on campus are demanding efficiency...and young people see the future because it is theirs".  And to wrap up his inspiring speech he said, "I don't want a legacy of something that caused problems in the ecosystem".

Dr. Francko said that working in the system is difficult, as the experts sometimes get in their on way, "it is frustrating to get a product through system, but it is good because they asked the hard questions- we have confidence in the product because we have been asked all the hard questions".  He also said that even he got in his own way sometimes, "I am a gardener-not a master gardener but I believe anyone can learn by doing- the masters sometimes are afraid to try stuff they don't know.  I got pushed by the Liquid Fence people to try work on a product for mature fruits and was afraid to do it- but the push got me over the hump.  I got caught in my own trap.  Don't assume something won't work when you don't have any data.  The proof is in the marketplace"

One of the reasons I truly liked speaking with Dr. Francko is he is clearly just a good guy.  When I asked him about why he decided to try and make this product he said, "When I talked to growers they told me if they could have gotten just three degrees this past season, they I wouldn't have lost their peach crop- it motivated me", and he added simply, "and it is just fun and you can't put a pricetag on fun". 

I think all of us gardeners can relate to that.  We're not getting rich from planting plants but it sure is fun.  Hopefully Freeze-Pruf will help us keep that party going longer in our gardens this winter, and as Dr Francko said, "This is not a miracle, but it does what it does very well."



  • Freeze-Pruf works best when you spray it on 24 hours before a frost, but will work for 4-6 weeks depending on rain.
  • If you are not going to use the pump that it comes with the product, make sure to clean the pump out very well before using it.
  • This is a Non-Toxic Product, made of all non-toxic materials.




Freeze-Pruf, Zone extender, Dr. David Francko


I checked out the Liquid Fence website and found the Freeze Pruf product. Here's the link:
Lily commented on 11/11/09
Thanks Lily- guess my journalism is a little shoddy :) I guess it really does work so we're all pumped up here in seattle as we are going to really be able to do some tropicals!!!
FigTree replied: on 11/11/09
No...your journalism is far from shoddy! I'm excited to try this product too...I lost my bananas last year to heavy frost...they came back but I had to stare at a bare back yard for awhile, and they're harvesting a bit late this year. I also have oranges and lemons that I'd like to protect. Everything else I have is pretty hardy to my zone. It's not the short cold spell, but the scorching sun that can be an issue! Is the company working on an herbal sunscreen?!?! :)
Lily replied: on 11/11/09
That is awesome! Our region's peaches were lost this year due to a late freeze. Hope this product works! Herbal sunscreen is a great idea! Maybe someone needs to suggest that be his next project!
gardengirl replied: on 11/11/09
This is amazing stuff!!!
Lily commented on 11/11/09
Where can you buy this stuff? Will it be showing up in garden centers soon? I could use 2 or 3 extra degrees here!!! I think it'd be a lot easier than blankets and hot lights!
Daylilyjoy commented on 11/10/09