I recently spoke at a City of Marco Island Waterways Committee Meeting about fertilizer leaching and run off causing algae blooms in our surrounding waterways. I learned that there are some citizens who are raising the idea of a complete fertilizer ban on Marco Island. This would not be a good idea since it could cause more pollution than it would stop by slowly killing the very plants that filter the pollution on our island. The same is unfortunately true of our fertilizer ordinance as it is today written. Both ideologies negatively affect roots.
Ah roots! The filters of our earth! And an important part of healthy lawns, trees and plants. And that brings me to the subject of soil, which is home to most roots. Soil should be alive and it is a fact that chemical fertilizers kill the microbial activity in soil. Do we really need chemical fertilizers for healthy lawns and plants? Fertilizers give us a quick bang for our buck. And homeowners and farmers have been using them for decades for growing food and to beautify our surroundings. Often to the detriment of our environment when too much is used or run off is not controlled. This is one of the main reasons that fertilizer is getting the bad rap it gets today. So what is a respectable farmer or gardener to do? Let us look into just what chemical fertilizers do to our soil and what the alternatives are.
We should know that chemical fertilizers have a negative impact on our soil by damaging soil structure, fertility and by devastating beneficial microorganisms. Fertilizer can change pH levels in the soil making erosion more probable. The lack of organic matter causes poor soil structure allowing it to wash or blow away and contaminate nearby waterways and their ecosystems.
Chemical fertilizers also disrupt the delicate balance of soil microorganisms like bacteria, fungi and other beneficial microbes. These microorganisms are crucial in decomposing organic matter, fixing nitrogen and fighting plant diseases. When you kill off beneficial microorganisms you reduce soil biodiversity. Mycorrhizal fungi, which I have written about in the past, are important for plant nutrient uptake and are just one example of important biodiversity. Altering soil’s microbial community affects the entire ecosystem.
Soil acidification is more of a problem in regions with low pH soils. We tend to have high pH levels due to our sandy, calcium soils. Soil acidification reduces soil fertility as nutrients become less available to plants. This can be a result of high pH soils. Fertilizers containing ammonium compounds can increase aluminum toxicity harming roots and microorganisms. And decreased microbial activity can accelerate soil degradation.
When we replace organic amendments like compost or manure with chemical fertilizer we reduce the building of soil organic matter. Organic matter is such an essential part of healthy soil. It improves soil structure and water holding capacity. It provides nutrients and energy for microorganisms which in turn supports soil biodiversity and ecosystems. Without organic matter soil is more prone to erosion, compaction and degradation along with a general decline in soil health. Chemical fertilizers can also increase the concentration of salts in the soil which affects the absorbing of water and nutrients.
So how do we wrangle ourselves from the unhealthy dependency we have on chemical fertilizer? There are sustainable practices that prioritize soil health, ecosystem services and environmental well-being. There is also the holistic approach allowing you to slowly make the change to organic. Integrated Nutrient Management combines organic and inorganic fertilizers tailored to your soil conditions and plant needs. Soil tests can lead you in the right direction with this option.
Purely organic fertilizers improve soil health and biodiversity over time. Most homeowners want that immediate nutrient boost they get from chemical fertilizers. It would take time (a year or so) to transition your yard to organic care and would likely mean losing that perfect lawn until your biodiversity begins to come alive again. But it would be worth the wait since it will lead to a more healthy and resilient landscape without harmful chemicals.
There are many non-chemical or abiotic options available. Here are a few I found online.
Espoma Organic – Derived from feather meal, poultry manure and sulfate of potash.
Jonathan Green Organic – Derived from feather meal, soybean meal, blood meal, sulfate of potash and calcium carbonate.
Fancy Chicken – Derived from 100% dried chicken manure w/calcium, magnesium, sulfer, copper, zinc, iron, molybdenum and carbon microbes.
Down to Earth – Bio Turf – Derived from Hydrolyzed feather meal, blood meal, meat meal, bone meal and Langbeinite.
Back to the Roots – Liquid – Derived from soy protein hydrolysate (a bio stimulant), with 1% iron for vibrant green and a mix of elements for plant, soil and microbes. Fish solubles, sugar molasses, corn steep liquor, soy protein hydrolysate, sugar beet extract, potash and kelp.
If you do decide to make the switch patience will be required. You will need to forgo all chemicals as you work to bring your soil alive again. This means no more chemical herbicides, insecticides or fungicides while you allow mother-nature to take over. There are some non-toxic options for these but the results are not the same as their chemical cousins. You don’t want to kill all those wonderful microorganisms you have worked so hard to bring back to life. Trust me. You won’t be sorry as your landscape becomes the envy of the neighborhood.