Fertrell offers a product called Sulfate of Potash (0-0-52), mostly referred to as S.O.P. Many of you may know this. Or maybe many of you have seen this on your Fertrell soil recommendations. But I have been seeing lately that many seasoned produce farmers do not know of this product. ALL ORGANIC PRODUCE GROWERS SHOULD KNOW ABOUT SULFATE OF POTASH!!!!! All larger fruiting crops will benefit from additional potassium throughout the season!!!!!
As I write this we are in the heart of the produce growing season. Therefore, I have been spending most of my days doing my best to help growers get the best results. I realize that when you are going to be reading this, fall will be upon us. So take this information and use it as part of your planning for the next season coming.
S.O.P is a 0-0-52. That means that is just above 50% potassium (also referred to as potash, or K). That means that in one 50 pound bag, you are getting just over 25 pounds of actual potassium. The product itself is naturally mined and it is water soluble. It is also OMRI listed. Fertrell brings this in by the skid and we sell it in a 50 pound bag. I state that again because you may use liquid potassium products. And the odds are that is the same product that is already mixed with water. We sell it straight, at a low cost, because we feel that is the most economically beneficial way to offer it to our customers.
So yes, this means that you will have to go through the extra labor of mixing it yourself. Some folks may think this is a pain. I would argue that it is very much worth it and that it will certainly pay you for the extra work. If you have higher PH water it may be tougher to mix. It is not 100% soluble so there will often be some residue left be left behind. We do recommend using hot water when mixing it. Some folks will mix it and let it set overnight. Also, some customer will mix it and strain it with cheese cloth or something like that. Those things seem to help people through the process.
Fertrell recommends the use of the S.O.P for larger fruiting crops throughout the season. We think tomatoes are a must to get the extra potassium. Other larger fruiting crops would include melons, peppers, squash, eggplants, and others like that. Generally we recommend 15-20 pounds (per acre), after first fruit set, to be run through drip lines every 7-14 days. If it works in your system to do this every week you could do 15 pounds. If every two weeks works for you, then 20 pounds per application should work.
Think of it this way; When you watch your tomatoes and you see that first fruit set that comes in real nice. Next, you see that second set that is just a bit smaller and so forth and so on. That is from a lack of potassium. Those plants are trying to produce so much that they cannot physically keep up with amount of K that they need to continue to size good tasting fruit all through the season. This comes even when your soils are at adequate levels of potash. Therefore, feeding additional potassium throughout the season will greatly improve your profitability throughout the growing season.
Sometimes I make the mistake of assuming every customer knows all about every product that Fertrell has to offer. I hope that if those of you out there who did not know of water soluble Sulfate of Potash, this explanation will help you to have a stronger management plan to put into your farming system. Please feel free to contact me at Seth@fertrell.com, our agronomy team, or comment below with any questions!