What are you using to get Potash and Phosphorus in an Organic Program

Discussion in 'Organic Lawn Care' started by gr8pyrs, Sep 1, 2003.

  1. gr8pyrs

    gr8pyrs LawnSite Member
    from PA
    Messages: 19

    I've started to use a cornmeal and corn gluten meal program for fert and pre-em control.

    What are you guys using to get the potash and phosphorus in the turf. Preferably something from a local feed mill or farm supply house.

    I am in the process of having the Ag Extension run a soils tests so I'm not sure what I might need yet but just want to be prepared.

    Also are there any adverse effects of using dolomitic lime in a program of this type?
    I mulch a lot of leaves and have used this in the past to control the acid (as well as fleas). Our soils here are acidic to start and with all the leaves it builds up.

  2. Dchall_San_Antonio

    Dchall_San_Antonio LawnSite Senior Member
    Messages: 327

    Check out


    for the NPK of different materials.

    Once you start using organic fertilizers, you might see a shift of soil pH toward neutral. This happens from both directions, acid and alkaline. The reason is that humic acids are tremendous buffers and they buffer right at pH of 7.0. As you build up your soil microbial numbers and their health, they will be spewing forth with humic acids to feed plants and neutralize the soil. Still, sometimes lime helps. A soil test should tell you.

    There is one soil test lab I am aware of that is very organic oriented. It is the Texas Plant and Soil Lab. Read about them at


    I would like to develop a list of organic oriented test labs, so please contribute when you find one.
  3. yardmonkey

    yardmonkey LawnSite Senior Member
    Messages: 341

    Bone meal can be good for phosphorus and greensand may be good for potassium. They may be expensive, but may not really be needed in great amounts. Many soils may already have plenty of P and K but just need more life to activate or release it. I'm wanting to work more with mainly adding compost. The city has been slow in making it this year but will soon release a bunch.

    Like Dave says, more organic matter should tend to even out PH. So compost or corn meal or any OM should be a step in the right direction. Of course the lawn would always be mulch-mowed. Some leaves are more acidic than others (I don't know which are what) and some break down faster than others.

    A friend of mine was telling me about using dolomitic lime in some kind of long-term organic lawn renovation project on clay soil.

    I have read that gypsum should adjust PH in either direction.

    But I would think that the healthier the soil, the faster it would "digest" mulched leaves, and the less PH problem there should be.
  4. gr8pyrs

    gr8pyrs LawnSite Member
    from PA
    Messages: 19

    Folks thanks for the responses.

    I reread all the posts on the "Organics" thread and found some of this info in your posts there.

    It's hard I guess to break the old x-x-x thinking process.

    Regarding the acid soils and the leaves that I have to deal with. With probably 70% of my lawn setting in between older growth trees, oaks, ashes, hickory, and maples; with some in excess of 120', I get some leaves. When I'm done in November mulching them, the lawn has a nice brown cast to it. :)

    That is the reason I have always used the lime. Of course I've not been on an organic program en total. I'd say probably a mixture. I mulch all lawn cuttings and leaves. I have done that now for about 6 years. I only used fertilizer, in most cases a local feed mill mix of 27-13-13 and never used herbicides or insecticides on the lawn since we raise dogs.

    The posts at LawnSite and the threads on organics peaked my interest. I've been looking for some method to improve the turf here i.e. weed & insect control but have always had the animals to consider. This has been good reading and I'm learning a great deal.

  5. Dchall_San_Antonio

    Dchall_San_Antonio LawnSite Senior Member
    Messages: 327

    I'm going to weigh in pretty heavily in a couple of days with a couple of organic turf care FAQs that I'm developing for y'all. They will cover the basics of what all works, why they work, and when/how to use them. They will be suitable for downloading to keep as a reference. Due to space limitations on Lawnsite, I'll have to make several different FAQs, so if you don't see it in one, look in the other(s).

    These FAQs will be works in progress. If I say anything really stupid, they are subject to revision. But for beginners, they will answer a lot of questions y'all have.
  6. gr8pyrs

    gr8pyrs LawnSite Member
    from PA
    Messages: 19

    Dchall, thanks.

    Your research and access to info is amazing.
    The engineering attention to details are showing. :D

    Looking forward to it.
  7. heritage

    heritage LawnSite Bronze Member
    Messages: 1,358

    What was your major in college? Texas A and M Ag school?......Soil science?......Do you have a PhD? Shall we call you the professor??????? We love all of the info you are putting up for us. Our lawns will surely look better now and our water will be safer and our applicators won't have to deal with cancer in 30 years.

    Pete D
  8. Dchall_San_Antonio

    Dchall_San_Antonio LawnSite Senior Member
    Messages: 327

    I did go to an ag school but studied aerospace engineering. For 5 years I lived in the dorm across from the ornamental horticulture unit at Cal Poly in Pomona, CA. That's about the limit of my academic credentials. I spent many an afternoon over there instead of studying. When I married, my wife decided to get a degree in ornamental horticulture, so I helped her study. There's no explanation for it but I still remember way more than I have a right to. I also have a masters in reliability engineering with sort of a minor in biomedical engineering. My last job was as a reliability engineer making policy for all the jet engines in the Air Force.

    I've been organic since retiring in April 2001. I realize that isn't a very long time, but I do read a lot. I'm also not so proud to admit when I'm wrong. I've learned a lot from being wrong.

    San Antonio is sort of the Compost Valley of the world. Something has attracted a lot of very proactive organic interest here. We have several huge compost manufacturers around here and 6 hours of radio air time devoted to organic gardening on weekends. One of these manufacturers alone makes enough compost to cover 800 golf courses from the 1st tee to the 18th hole per year. So we sort of feed on each other.

Share This Page