How do soils store water soluble minerals and plant nutrients without them leaching out?
August 18, 2009 by Organic Farmer
Filed under Yahoo Answers on Organic Fertilizers
It’s a well known fact that if the same field is used for decades to grow the same crop (eg garlic) then the soil becomes depleted of minerals this crop uses most (eg. sulfur), this is why crop rotation is sometimes used.
However plants can only absorb minerals when they are already dissolved in water. How are plants able to “deplete” the soil of its minerals if they only absorb minerals which should leach out either way?
Also, water soluble chemical fertilizers such as miracle grow state on the label that they last for 8 weeks. Why don’t they leach out on the next watering?
Apparently there must be some mechanism which holds these water soluble nutrients in place in the soil if plants don’t use them – what is this mechanism? Do they get stored inside the cells of bacteria and fungi in the soil? Or chemically bind to clay particles or hummus? Or some other process?
I’ve tried googling this to find out how exactly soils store their nutrients and can’t find an answer.
By: Nathan W
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A Closer Look At Organic Lawn Fertilizers
March 7, 2009 by Organic Farmer
Filed under A Closer Look At Organic Fertilizers
In order to have the lush green lawns most homeowners dream about, proper care and maintenance is required. One of the ways to get and keep a beautiful green lawn is in the use of lawn fertilizer. There are many choices in fertilizers, but the most environmentally safe is organic lawn fertilizers.
One reason organic fertilizers are often used is the time release abilities of this type of lawn care. Slow release means a steady supply of nutrients needed to grow a green healthy lawn is fed into the soil. This results in millions of new tiny plants sprouting over time. As the nutrients are released into the soil, the new grass seeks out nutrients needed for healthy growth. As the new grass spreads out in a carpet affect, it covers the bare areas that needed grass with new, healthy growth. The use of organic fertilizer also inhibits weed growth as the areas are covered with new grass spouts. The weeds no longer have room to grow.
As with any live plant, grass also needs the correct amount of nutrients to achieve maximum capability. Without nutrients, the grass couldn’t transform some atmosphere chemicals into something healthy and beneficial to the plant. It can even provide the plant with carbon dioxide for photosynthesis, and help ward off many plant diseases and fungi.
Many chemical substances found in synthetic fertilizers can actually inhibit the natural microorganisms that promote a healthy plant. Organic lawn fertilizers are known to be all natural and not harmful to the microorganisms or other plant life, therefore encouraging the growth of the healthiest plants available, grass or otherwise.
Another benefit of organic lawn fertilizer is the reduction in thatch because of better soil aggregation. This causes more of the nutrients released by the fertilizer to go directly to the grass. Fertilizer also aides in the increased amount of water and oxygen retention, allowing the grasses root system to grow deeper and stronger. Fertilizer also helps in the reduction of plant diseases as it increases the antioxidant hormone production. The benefits of using an organic lawn fertilizer are more than a beautiful green lawn, it is environmentally safe also. The fertilizer enables proper water infiltration adding to the health of the lawn.
All three of the most important nutrients needed by a healthy lawn can be found in manufactured organic lawn fertilizers. When purchasing an organic fertilizer for grass, it should contain nitrogen, phosphorus and potassium. Using organic lawn fertilizer insures the grass gets the nutrients it needs to be green lush and thick.