Jumping in late to defend Epsom Salts as an organic substance. I've seen it called a chemical and a salt in several threads recently, but I haven't had the necessary time to research what I've always believed, that Epsom Salts are organic. This morning, I was able to find the following two links to support this belief. There are many, many more out there, but I liked these two best for their simplicity:rainbowgardener wrote:Epsom salt is a salt (not table salt, but a salt, in chemistry defined as ionic compounds that result from the neutralization reaction of an acid and a base) as are synthetic fertilizers. Salts tend to build up in the soil and ultimately kill off some of the soil bacteria and other life of the soil.
[url=https://www.livestrong.com/article/282344-what-minerals-are-in-epsom-salt/]Livestrong[/url]: "Epsom salts are generally found in crusts that form in the dry areas of outcrops of rocks or inside caves. Epsom salts can also be found on the walls of copper and coal mines, and as deposits in dried-up salt lakes or springs. . . . It is thought that Epsom salt was termed a salt because its crystalline structure resembles that of table salt, but it is actually a pure mineral compound."
[url=https://blog.gardenerd.com/2008/10/23/epsom-salts.aspx]Gardenerd[/url]: "Since Epsom Salts are 'of the earth', meaning they are a harvested product found in well water, they is [sic] considered organic, and subsequently are considered safe for organic gardening."
Many organic gardeners use it as a regular amendment. I use it only to correct a problem with calcium deficiency caused (I believe) by overwatering, which reduces the plant's ability to process calcium. I'm not certain why it works, but it does. I think it has something to do with balancing the minerals, increasing the plant's ability to uptake the calcium, but I'm not sure
