a bunch of mulched up leaves

Discussion in 'Organic Lawn Care' started by tkalafut, Nov 3, 2003.

  1. Dchall_San_Antonio

    Dchall_San_Antonio LawnSite Senior Member
    Posts: 327

    One generally accepted organic practice is to continue to mulch/mow the lawn at the same height. Some yards have quite a bit of litter and need to be mowed more often or make several passes to keep from smothering the grass (as GroundKprs said). In organic yards pH is not usually a consideration when mulch/mowing leaves.

    What is good about mulching leaves into the soil is that they require fungi to decompose them, and lawns are woefully short on good fungi. If you cover the top of the grass with leaves and leave them for the winter, you will undoubtedly develop disease fungi under there. But when you chop them fine and allow them to drop in between grass blades, there is too much air circulation for the disease fungi to develop.

    The other way to get fungi into the lawn is to use a fungally dominated compost or a fungal compost tea regularly.
     
  2. dvmcmrhp52

    dvmcmrhp52 LawnSite Platinum Member
    from Pa.
    Posts: 4,205

    David,
    educate me,
    Why is ph not usually a consideration in organic lawns when mulching leaves?
     
  3. Dchall_San_Antonio

    Dchall_San_Antonio LawnSite Senior Member
    Posts: 327

    pH is not usually a concern in organic turf because there is such a predomination (is that a word? - must be; my spell checker let it go) of humic acids in the soil. Humic acids are buffered acids. This means it takes a LOT of strong acid or strong base to change the pH of a buffered acid even just a little. The humic acids are buffered right at a pH of 7.00000000 - maybe a little less or more. Once the microbes have been cranking on organic fertilizer for a year or so, the buffered humic acids will predominate and it becomes very hard to change the pH - especially by adding a weak acid like tannin from tree leaves. Out in the wild, the pH is usually held between 6.5 and 7.5 with healthy microbes.

    Lawns that have not had much organic fertilizer applied in the past will act different. These lawns have no wealth of healthy microbes in there building up humic acids. (by the way, humic acids are very dark brown to black in color; hence the fertility of the black land soils) Some organic fertilizers, ammonium sulfate in particular, are strong acidifiers and will lower the "unprotected" soil pH toward the acid side with relative ease. In fact the pH can be lowered to the point where it becomes difficult to reestablish healthy microbes in the soil without a pH adjustment with lime.
     
  4. dvmcmrhp52

    dvmcmrhp52 LawnSite Platinum Member
    from Pa.
    Posts: 4,205

    Thanks David.
     

Share This Page