Sweet Sorghum for Carbon Farming

I would like to take this opportunity to beat the drum of sweet sorghum cultivation as a valuable carbon farming option.

It's an annual crop that produces 20+ tons of biomass per acre, which you crush to extract the juice and make sorghum syrup (to me the taste is somewhere between honey & molasses).  The leftover stover/bagasse can be turned into biochar that goes back into the soil (I'm setting it up to use the heat of pyrolysis to cook the juice down into syrup).  And unlike corn, sorghum has a very deep root system (up to 6' down) -- not only does this make the crop highly drought resistant, it also means you have tons of zero-effort carbon sequestration deep down in the soil.  I'm told it also does a great job of busting through hardpan soil structures to improve drainage, which for some folks can mean earlier planting dates and an extended growing season.

Penn State recommends planting a fall cover crop of hairy vetch + oats, then mowing it or rolling it over in the spring, and broadcasting the sorghum seed into the resulting mulch.  I'm thinking of applying the previous season's biochar right before the mowing/rolling step.

Very interesting! I bought a (small) packet of sweet sorghum seeds this spring and am trying it out on a small plot. It seems like a multipurpose plant, as I hope to extract the cane syrup, use the seeds as poultry/pig fodder, and the biomass for mulch or biochar.
I'm still quite new to the concept of carbon farming, so I'm happy to learn that I can add that to the list of functions of the sweet sorghum! Thank you for sharing!

It is excellent rabbit fodder, even if you don't let it go to the end of the seed production cycle. I have a few crops I plant for forage and soil improvement, and sorghum is one (black oats and forage radish are others). The rabbits are absolutely crazy about it.
KC, because my space is so small, I often "coppice" it (cut individuals before they are fully mature and let them grow back) and often can get two harvests. You might find that helpful if you're just testing with a small plot and feeding it to chickens.

We raise sweet sorghum here.  We use it for silage, grain, and molasses.  It grows well here once the ground gets warm enough to sprout.  We usually plant it the last week of may. We rotate it in with corn and hay.  It is a heavy n feeder so, the fields need lots of organics to keep the worms working.  We have spread our seed around as far as W.V.  The seed heads are good for boosting egg production and we have to be carful to not give the chickens to much.

Tereza Okava wrote:It is excellent rabbit fodder, even if you don't let it go to the end of the seed production cycle. I have a few crops I plant for forage and soil improvement, and sorghum is one (black oats and forage radish are others). The rabbits are absolutely crazy about it.
KC, because my space is so small, I often "coppice" it (cut individuals before they are fully mature and let them grow back) and often can get two harvests. You might find that helpful if you're just testing with a small plot and feeding it to chickens.

Good info to know!
My show rabbit herd's diet is pretty much a total pellet diet to help maintain wool & body condition, but I've been experimenting with providing more forage for the meat rabbit herd, so will need to try that out.
Even as rabbit fodder, it'll still be sequestering carbon since pretty much all my rabbit poop goes in the worm bins, compost, or under the soil surface (as do the rabbits once their lives are over).

It looks very interesting to me.  I've got a worn out hay field and a cleared sections of alders that I need to improve.  It's also clay with a hardpan, so I need plants to start to work away at it.  

I'm also intrigued by sorghum beer.  I think I'll give that a shot if I can grow some.  

Timothy Markus wrote:It looks very interesting to me.  I've got a worn out hay field and a cleared sections of alders that I need to improve.  It's also clay with a hardpan, so I need plants to start to work away at it.  

I'm also intrigued by sorghum beer.  I think I'll give that a shot if I can grow some.  

Sounds like your hay field is a good candidate for sweet sorghum. But as for beer, you'll want to try a grain variety of sorghum. Since sweet sorghum leaves loads of sugar in the stalk, there's less starch in the seed, and it's really hard to thresh. But any other variety of sorghum should do.

Nathanael Szobody wrote:
Sounds like your hay field is a good candidate for sweet sorghum. But as for beer, you'll want to try a grain variety of sorghum. Since sweet sorghum leaves loads of sugar in the stalk, there's less starch in the seed, and it's really hard to thresh. But any other variety of sorghum should do.

I think I'd mash the whole stalk or do some sort of variation of that.

Timothy Markus wrote:I'm also intrigued by sorghum beer.  I think I'll give that a shot if I can grow some.  

Great to see so many folks (already) interested in growing sweet sorghum.  

It bears mentioning that some varieties (e.g., Mennonite) are meant to be multipurpose, i.e., you can either crush the stalks for the sugary juice, or you can let the seedheads fully develop for grain.  And there are MANY opportunities for fermentation   You can ferment the juice directly (15-20 Brix), you can ferment the syrup (80 Brix) to make a vegan version of mead, you can distill that product to make a spirit similar to rum, and finally you can also use the grain to make a gluten-free beer.  A good time was had by all!

For those interesting in harvesting the juice, I had decent success with this relatively inexpensive roller press.  It's meant for sugarcane, but it has an adjustable pressure plate so that it can be used with smaller diameter feedstock like sorghum too.  There are many like it out there on the market (but all sourced overseas unfortunately).  This year I'll be adding an electric belt drive.

$250 Roller Press on Amazon

Oh my goodness!! How is it that I am just now stumbling onto this forum?

Y’all are awesome!! So many brilliant farmers and homesteaders here! Anyone (else) using sorghum w hemp?

Part of the “Southern Belle  Hemp Co-Op” mycorrhizal-based growing system protocol is interplanting Sorghum because it has also been proven to increase sugar activity in the soil... (thus increase mycorrhizal activity and thus nutrient exchange) in addition to the many benefits and uses mentioned here.
I like to cut it back early to encourage branching and root growth (thus increased carbon sequestration), and then use it as a living trellis to Florida weave support between sorghum and hemp.

Check out @southernbellehemp if you want to learn more!!

Hi Annie and welcome to Permies.  How much sorghum do you plant with the hemp?

do you mean www.southernbellehemp.com the Wordpress site?

Welcome Annie! Look forward to hearing from you!

We were just talking about using this its as if permies reads my mind and leads me to the proper threads lol. Great info ty