Soil amendments
Posted: Thu Mar 26, 2020 11:06 am
I found this in a gardening magazine the other day and thought it was interesting.
About soil amendments
A plant’s primary nutrients are nitrogen (N), phosphorous (P), and potassium (K). These are available in chemical/synthetic (nonorganic) fertilizers (on the package, the number for each nutrient indicates the percentage of net weight contained) or as organic additives.
Nitrogen promotes strong leaf and stem growth and dark green color, as is desired in broccoli, cabbage, greens and lettuce, and herbs. Add aged manure to soil and apply alfalfa meal or fish or blood meal to increase available nitrogen.
Phosphorous promotes root and early plant growth, setting blossoms, developing fruit, and seed formation. It’s important for cucumbers, peppers, squash, tomatoes, and any edible that develops after a flower has been pollinated. Add bone meal (fast-acting) or rock phosphate (slow-release) to increase phosphorous.
Potassium promotes plant root vigor, disease and stress resistance, and enhances flavor. It’s vital for carrots, radishes, turnips, onions and garlic. Add green sand, wood ash, gypsum, or kelp to increase potassium.
Avoid applying excess chemical/synthetic fertilizer. It can damage roots and/or reduce the availability of other elements. It is virtually impossible to over-fertilize with organic fertilizers. Plants cannot distinguish between synthetic and organic fertilizers.
Soil fixes
Clay soil – add coarse sand and compost (no fine sand)
Silt soil – add coarse sand or gravel and compost, or well-rotted horse manure mixed with fresh straw (no fine sand)
Sandy soil – add humus or aged manure, or sawdust with some extra nitrogen, or some heavy clay rich soil
Pounds per ton
Type of manure Water content Nitrogen Phosphorous Potassium
Cow, horse 60-80% 12-14 5-9 9-12
Sheep, pig, goat 65-75% 10-21 7 13-19
Chicken
Wet, sticky, and caked 75% 30 20 10
Moist, crumbly to sticky 50% 40 40 20
Crumbly 30% 60 55 30
Dry 15% 90 70 40
Ashed none none 135 100
Type of Garden Best Manure Best Time
Flowers Cow, horse Early spring
Vegetables Chicken, cow, horse Fall, spring
Potatoes and root crops Cow, horse Fall
Acid-loving plants Cow, horse Early fall or not at all
About soil amendments
A plant’s primary nutrients are nitrogen (N), phosphorous (P), and potassium (K). These are available in chemical/synthetic (nonorganic) fertilizers (on the package, the number for each nutrient indicates the percentage of net weight contained) or as organic additives.
Nitrogen promotes strong leaf and stem growth and dark green color, as is desired in broccoli, cabbage, greens and lettuce, and herbs. Add aged manure to soil and apply alfalfa meal or fish or blood meal to increase available nitrogen.
Phosphorous promotes root and early plant growth, setting blossoms, developing fruit, and seed formation. It’s important for cucumbers, peppers, squash, tomatoes, and any edible that develops after a flower has been pollinated. Add bone meal (fast-acting) or rock phosphate (slow-release) to increase phosphorous.
Potassium promotes plant root vigor, disease and stress resistance, and enhances flavor. It’s vital for carrots, radishes, turnips, onions and garlic. Add green sand, wood ash, gypsum, or kelp to increase potassium.
Avoid applying excess chemical/synthetic fertilizer. It can damage roots and/or reduce the availability of other elements. It is virtually impossible to over-fertilize with organic fertilizers. Plants cannot distinguish between synthetic and organic fertilizers.
Soil fixes
Clay soil – add coarse sand and compost (no fine sand)
Silt soil – add coarse sand or gravel and compost, or well-rotted horse manure mixed with fresh straw (no fine sand)
Sandy soil – add humus or aged manure, or sawdust with some extra nitrogen, or some heavy clay rich soil
Pounds per ton
Type of manure Water content Nitrogen Phosphorous Potassium
Cow, horse 60-80% 12-14 5-9 9-12
Sheep, pig, goat 65-75% 10-21 7 13-19
Chicken
Wet, sticky, and caked 75% 30 20 10
Moist, crumbly to sticky 50% 40 40 20
Crumbly 30% 60 55 30
Dry 15% 90 70 40
Ashed none none 135 100
Type of Garden Best Manure Best Time
Flowers Cow, horse Early spring
Vegetables Chicken, cow, horse Fall, spring
Potatoes and root crops Cow, horse Fall
Acid-loving plants Cow, horse Early fall or not at all