One of the most used amendments in my garden is Texas Glauconite Greensand. It is amazing stuff and if you live in an area where St. Augustine grass is popular, then you need this product. It is mostly glauconite (potassium silicate) but contains an abundance of other minerals. If you can get your hands on it, and you should be able to find it, it makes a great addition to any veggie or herb garden.
We were lucky to get some established St. Augustine at our current house when we moved. It is an older house and this grass was well established and slowly overcoming the bermuda areas. Why did the last guy have two different kinds of grass? Probably for the same reason he fixed his sink drain with duct tape and string (suprisingly it is still holding up after two years, just a little odd experiment we have going on), or collected milk jug pull tabs behind the fridge, or stockpiled chickenwire…but I digress. Anyhow, it was nice having this type of grass because I grew up with it and enjoy the feel over coarse bermuda, which is the other established grass. However, the grass beamed with this horrid yellow color despite being well watered.
Enter greensand. I had heard much about this stuff in my readings of local gardening gurus (who’s books I will begin reviewing soon) and they all said it was a wonderful product. It is mostly ocean sludge from a former bank of prehistoric ocean, so it contains mineral and nutrient remnants from a lot of different kinds of animals. It is mostly a potassium product, but it comes replete with iron, calcium, phosphorous, magnesium and many trace minerals being an ocean product. Well, former ocean product.
St. Augustine greens with potassium and iron, not needing much nitrogen, unlike bermuda or some other grasses. Potassium, a mobile nutrient, will move with water and wash away in heavy rains, which at the time we were having (they are free to return at any time too, hint hint, ma nature). Yay water, boo yellow grass.
So from the get go we started broadcasting greensand. I would try to hit it when a storm was on its way so it would get washed right to the root zone. This worked well, and you could see some recovery, but, and you will read this in many places, the stuff only really starts to work after a year of putting it on. That is exactly what would happen. The grass would be bitchin’, then it would go yellow in spots. This went on for a year.
During the winter of ’07 I put my last bag out. We had used a bunch the first year preparing the beds and treating the grass, and I cant remember how much we went through, but my gut says at least 8 forty pound bags over the year. Well, come spring ’08 the grass is solid green, and looking great. The only thing that will yellow the grass is drought (I try not to put too much water on my lawn, so it usually looks like crap), but even then the yellow is very hard to see. So here’s to success.
We have not bought any more since the last bag used over winter, yet. I will most likely be buying a bag to use for planting in veggie starts as the summer wears on, and on, and on, and on (damned two season states). I may also get a bag to put down on the lawn once, hopefully before a big rain.
Last year I had a new raised bed show potassium deficiency in my tomatoes
, and some sul-po-mag and greensand cleared it up within a weak or so, no fussing necessary. Just dump the stuff around the plants and water, presto.
You can’t use too much, unless your try to grow in it straight, but a little goes a long way once you get a good soil food web going. I hope to keep it down to two bags this year. Really, nothing has shown a need for it.
But what about heavy rains? That is where the soil food web comes into play, as it will keep these nutrients bound in humates. If your soil is not alive, it will all just wash away and need replenishing. Florida residents growing on sand know all about this I am sure. Lots of rain and little substrate for soil life.
For the vermicomposters (worms) out there, I would use this as a partial ingredient in my “grit” for the wormies, but more on all that later.
It is a mined product, and should not be overused if that begins to occur. That said, it is mostly a detritus derived mineral from shelled creatures and dead fish from long ago. Since a constantly replenishing shower of dead aquatic life (hmm, dead life huh?) rains down to the ocean floor, this may not be so finite a resource, but I haven’t looked into to it much, so chime in if you have something to add.
Bottom line, way down here, and thanks for reading, is to get some and use it and enjoy the results. In a year you will glad you did.