PressuredLeaf
Well-Known Member
Hi everyone,
The importance of potassium in tobacco is something I’ve been researching on and off for a few years. Not only is K important for overall plant health, but it’s also essential to good combustion. This last point is something I’ve been struggling with ever since growing my own. I could grow beautiful plants here in AZ that cured well, and smelled amazing. However, they were basically fireproof. I could take a cured dried leaf, heat it with a direct flame and the oils would flash off. As soon as the flame was removed the tobacco would instantly go out, no ash, just charred tissue.
Initially I thought this was due to bad curing and fermenting. So I built a temperature and humidity controlled chamber, and kilned all the tobacco that came out if it. Still, no improvements in combustion!!
At this point, I began researching more. I had found that chloride (as mentioned here before) can be detrimental to combustion. However, my soil test showed my garden is very low in chloride. Further reading into old American publications made reference to excessive sulfate as being an issue in some cases. That clicked because I had added a boat load of elemental sulfur to my garden to correct the pH. However, something I couldn’t really reconcile was the idea that sulfate alone was the issue. For starters, many fertilizers are sold as their sulfate salt. Second, plants in general will limit the amount of sulfate they absorb. Certain species, like brassicas and onions absorb more, but for the most part many plants are vacuuming up all the S in the soil.
So I went back to researching. This has been difficult because the USA hasn’t really published any good science or nutrition studies on cigar tobacco in a quite a long time. There are some from China, but it’s still few and far in between. I stumbled upon an article from the 1960s (I think), where the authors were trying to elucidate the effect of the different alkali metals on the combustion of cigar tobacco. Essentially, they took tobacco leaves, hydrated them, and nebulized the leaves with various salts and looked at how they burned to try and find some sort of correlation.
I’m have trouble finding the article, but luckily I took a screen shot:
The gist of the article was that misting tobacco leaves with a 2% solution of potassium carbonate accelerated burning quite a bit. They also tested other salts like Cesium and rubidium carbonate, but that’s not something you would want to smoke.
When I read this article I had to try it. I made a 2% solution of food grade potassium carbonate in RO water and misted down a few leaves of my wonderful smelling fire proof little Dutch from a few years ago. I put it in a bag to hydrate and reach equilibrium. Upon opening it, my nose was hit with ammonia. Which is something I hardly ever saw when curing my home grown.
The treated tobacco took much longer to dry, and it stayed in the “medium case” zone a lot longer than my regular tobacco. This makes sense since a lot of potassium salts are hygroscopic and hold onto moisture pretty tenaciously. Once the leaf was in low case I grabbed a piece and burned it. As soon as the flame was taken away I had a orange ember and a few wisps of smoke! It went out about 5 seconds later but I was ecstatic! Never ever has my homegrown burned remotely as well as that little piece of treated leaf.
So I misted up the bag of tobacco, which is a mix of little Dutch and corojo. I also rolled a small cigar which is currently drying. Smoke report to come soon.
I’m not advocating treating tobacco with chemicals, but potassium carbonate is very benign. In fact potassium bicarbonate is used as “organic” spray to control powdery mildew and other funguses on tobacco and many food crops. This had me speculating that farmers spraying for mildew may inadvertently be improving the combustion of their tobacco.
This also led me to another thought. Remember the stories passed around about Bethune (or however you spell it)? For those of you who don’t know, apparently it’s a secret sauce used by some farmers speculatively composed of herbs, spices, alcohols etc. For the farmers that do use it, the recipes are guarded more than kernel sanders chicken spices. One curious thing I have noted is that many of the supposed recipes include tobacco stalks. This is very interesting to me because the stalks accumulate large amounts of potassium relative to the leaves. So, I doubt the herbs and alcohol do anything, but leaching the K out of the stocks probably helps the treated leaves combust. Most of the stories around Bethune come from Cuba. While Cuba has some very nice soils in certain areas, a lot of the soils there are weathered and in high precipitation areas. This tends to leach solubles like K out of the soil. And unless properly supplemented, there are going to be deficiencies. So Bethune may have been born out of necessity before proper tobacco fertilization was developed. On the contrary, areas like Esteli in Nicaragua have much younger soils and are consequently much higher in K, so no Bethune needed.
Overall the takeaway from this is K is very important for combustion, typically I’ve seen 2.5% dry weight as the min for good burning tobacco. If a dry plant produces ~ 6oz of plant material, well that’s a lot of potassium per acre! If your fertilizing well or already have good soil fertility, it’s probably not an issue. But if you have fire proof tobacco like me, and are too stubborn to call it a loss, spritzing the leaf with food grade potassium carbonate may be an option.
I’m sure the farmers know the importance of proper K nutrition, but I thought I would share this for everyone. It took me a while to connect the dots, and I hope it’s helpful for someone who grows nomex tobacco like me.
The importance of potassium in tobacco is something I’ve been researching on and off for a few years. Not only is K important for overall plant health, but it’s also essential to good combustion. This last point is something I’ve been struggling with ever since growing my own. I could grow beautiful plants here in AZ that cured well, and smelled amazing. However, they were basically fireproof. I could take a cured dried leaf, heat it with a direct flame and the oils would flash off. As soon as the flame was removed the tobacco would instantly go out, no ash, just charred tissue.
Initially I thought this was due to bad curing and fermenting. So I built a temperature and humidity controlled chamber, and kilned all the tobacco that came out if it. Still, no improvements in combustion!!
At this point, I began researching more. I had found that chloride (as mentioned here before) can be detrimental to combustion. However, my soil test showed my garden is very low in chloride. Further reading into old American publications made reference to excessive sulfate as being an issue in some cases. That clicked because I had added a boat load of elemental sulfur to my garden to correct the pH. However, something I couldn’t really reconcile was the idea that sulfate alone was the issue. For starters, many fertilizers are sold as their sulfate salt. Second, plants in general will limit the amount of sulfate they absorb. Certain species, like brassicas and onions absorb more, but for the most part many plants are vacuuming up all the S in the soil.
So I went back to researching. This has been difficult because the USA hasn’t really published any good science or nutrition studies on cigar tobacco in a quite a long time. There are some from China, but it’s still few and far in between. I stumbled upon an article from the 1960s (I think), where the authors were trying to elucidate the effect of the different alkali metals on the combustion of cigar tobacco. Essentially, they took tobacco leaves, hydrated them, and nebulized the leaves with various salts and looked at how they burned to try and find some sort of correlation.
I’m have trouble finding the article, but luckily I took a screen shot:
The gist of the article was that misting tobacco leaves with a 2% solution of potassium carbonate accelerated burning quite a bit. They also tested other salts like Cesium and rubidium carbonate, but that’s not something you would want to smoke.
When I read this article I had to try it. I made a 2% solution of food grade potassium carbonate in RO water and misted down a few leaves of my wonderful smelling fire proof little Dutch from a few years ago. I put it in a bag to hydrate and reach equilibrium. Upon opening it, my nose was hit with ammonia. Which is something I hardly ever saw when curing my home grown.
The treated tobacco took much longer to dry, and it stayed in the “medium case” zone a lot longer than my regular tobacco. This makes sense since a lot of potassium salts are hygroscopic and hold onto moisture pretty tenaciously. Once the leaf was in low case I grabbed a piece and burned it. As soon as the flame was taken away I had a orange ember and a few wisps of smoke! It went out about 5 seconds later but I was ecstatic! Never ever has my homegrown burned remotely as well as that little piece of treated leaf.
So I misted up the bag of tobacco, which is a mix of little Dutch and corojo. I also rolled a small cigar which is currently drying. Smoke report to come soon.
I’m not advocating treating tobacco with chemicals, but potassium carbonate is very benign. In fact potassium bicarbonate is used as “organic” spray to control powdery mildew and other funguses on tobacco and many food crops. This had me speculating that farmers spraying for mildew may inadvertently be improving the combustion of their tobacco.
This also led me to another thought. Remember the stories passed around about Bethune (or however you spell it)? For those of you who don’t know, apparently it’s a secret sauce used by some farmers speculatively composed of herbs, spices, alcohols etc. For the farmers that do use it, the recipes are guarded more than kernel sanders chicken spices. One curious thing I have noted is that many of the supposed recipes include tobacco stalks. This is very interesting to me because the stalks accumulate large amounts of potassium relative to the leaves. So, I doubt the herbs and alcohol do anything, but leaching the K out of the stocks probably helps the treated leaves combust. Most of the stories around Bethune come from Cuba. While Cuba has some very nice soils in certain areas, a lot of the soils there are weathered and in high precipitation areas. This tends to leach solubles like K out of the soil. And unless properly supplemented, there are going to be deficiencies. So Bethune may have been born out of necessity before proper tobacco fertilization was developed. On the contrary, areas like Esteli in Nicaragua have much younger soils and are consequently much higher in K, so no Bethune needed.
Overall the takeaway from this is K is very important for combustion, typically I’ve seen 2.5% dry weight as the min for good burning tobacco. If a dry plant produces ~ 6oz of plant material, well that’s a lot of potassium per acre! If your fertilizing well or already have good soil fertility, it’s probably not an issue. But if you have fire proof tobacco like me, and are too stubborn to call it a loss, spritzing the leaf with food grade potassium carbonate may be an option.
I’m sure the farmers know the importance of proper K nutrition, but I thought I would share this for everyone. It took me a while to connect the dots, and I hope it’s helpful for someone who grows nomex tobacco like me.
