As the summertime heat and humidity begin to move into the
Lowcountry, I want to remind you of some of the benefits of using organic
fertilizers, composts, mulch, wetting agents with biostimulants, and bridge
products. Some of the things I write about are generalizations (ex. 10-10-10 is
all synthetic – a fertilizer blender could put organic filler in the formula,
but not likely).
When you purchase a typical 10-10-10 fertilizer, you are
getting 30% nutrients and the rest of the bag is filler (70%). Filler usually
consists of drying agents to keep the fertilizer from absorbing moisture and
becoming clumpy. Filler is also limestone or other non-nutritional ingredients.
The nutrients in a 10-10-10 are water soluble so the plant can absorb them. The
10-10-10 is usually all fast release, so once it goes out the plant better be
ready to take it in, or the Nitrogen (what part hasn’t already volatized into
the atmosphere as N2 gas) and the Potassium will leach through the soil profile
or run-off into non-target areas.
Unlike humans, plants uptake only the nutrients that they
need. No obese plants out there! A natural or organic fertilizer may have a
lower N-P-K ratio; however, all the ingredients are either a food source for soil
organisms, plant essential minerals or micro-nutrients. Organic fertilizers are
not water soluble, and depend on beneficial soil organisms to convert the
nutrients into a form that the plant can uptake. This is the same process that feeds
the trees from fallen leaves and limbs in the woods. This process is the true,
original slow release fertilizer. Nothing is lost to evaporation or run-off
which is good with all the water around here.
With an organic fertilizer you generally have slow steady
growth as the soil organisms meter out the nutrients. Slow steady growth is
easier to maintain and less susceptible to disease and insect attack. The plant
will grow deeper roots, making it more drought tolerant; therefore requiring
less water (lower water bill).
A 10-10-10 might cause “flush growth” that requires more
hedge trimming or mowing. The plant will be more susceptible to disease and
insects. Excessive fertilization could also add to thatch in the lawn areas. A
plant that is putting out a lot of new growth is often sacrificing root growth
for top growth and the landscape needs more water as a result.
Well, I’m out of column inches, so I will have to continue
next week.
