Growfood.com » Problems with Using Manure in the Vegetable Garden

Problems with Using Manure in the Vegetable Garden

Are there really problems with using manure and compost in your garden?  I’ve listed seven main areas where problems occur, and a couple of dozen statements on the details.

I.The nutrient value of manure/compost is unknown:
A. Nutritional adequacy and balance in the original plants is unknown
B. Much is lost before it reaches your plants:
a. Animal which ate the plant received a substantial amount
b. About half of remaining nutrition is lost in urine.
c. Some of remaining nutrition is lost to leaching during composting
d. Nitrogen is lost into the air due to volatility
e. More nutrition is lost during decomposition – see III below

II. Not clean because very rarely composted with sufficient heat (140 degrees F) to remove:
A. Weed seeds
B. Diseases – plant and/or human
C. Bugs

III. Nutrients are not water-soluble and available to plants. They must be changed from organic to water-soluble inorganic minerals through decomposition in the soil.
A. Takes time, so plants do not receive immediate benefit
B. Some nutrition lost to:
a. Micro-organisms, worms, etc.
b. Leaching,
c. Fixation in the soil

IV. Availability is very limited.  There is only enough manure in the world for a very small percentage of people to grow gardens, especially in urban areas, where most people live. And during crisis situations there will likely be much less.

V. Cannot easily be stored for later use due to:
A. Bulk,
B. Cost
C. Smell
D. Pests and diseases

VI. Common practice of applying large amounts before planting the garden:
A. Puts 10-20 times more mineral salts into the soil than plants need
B. Often burns and kills emerging seedlings
C. Excess salts are leached into the ground water, killing life downstream and damaging water supplies
D. Nutrition is gone by early-mid summer, and ever-bearing plants stop producing right at what should be their peak.

VII. To ensure clean crops, restrictions on manure use are applied:
A. “Certified” organic growers must cease feeding with manure 120 days before harvest with plants where edible parts touch the soil, and 90 days before harvest with plants where edible parts do not touch the ground.
B. Nutrient deficiencies are virtually guaranteed in that time frame.
C. Salmonella, e-coli, etc. problems occur when manure is used.