Fertilizers and Amendments

FERTILIZER

N-P-K

DESCRIPTION

 Alfalfa Meal

(3-2-1)

Ground or pellets. Increases organic matter in soil, plant based and contains natural growth stimulant triacontanol.

 Ammonium sulfate

(21-0-0)

Fast acting, concentrated N, increases acidity, contains 24% sulfur.

 Bat guano

(9-3-1)

Rich in readily available nitrogen, phosphorous and micronutrients.

 Blood meal

(12-0-0)

Derived from animal blood, contains readily available N with iron and trace minerals. Lasts 2 months.

 Bone meal steamed

(3-15-0)

Good source of slow release P and calcium (15-22%). Good for bulbs and root crops. Lasts 6-12 months.

 Chelated iron

Iron is chelated to make it readily available for plant uptake, through leaves and roots.

 Compost tea

Made from plant-based compost. Do not use animal manure compost. Apply judiciously to avoid harmful leaching.

Cottonseed meal

(6-2-1)

All-purpose slow release fertilizer for acid loving plants: azaleas, roses, blueberries. Last 6-12 months.

Dolomite Lime

Calcium 23%, magnesium 9.5%, Calcium carbonate 49.8%, magnesium carbonate 32.9%Supplies magnesium and calcium while raising pH. Do not use without soil testing to verify deficiencies and pH of soil.

Epsom salts

Magnesium sulfate highly soluble form of sulfur (13%) magnesium (10%) for leaf growth and plant development.  can be applied as foliar spray.

Feather meal

(12.8-0)

High N, slow released over 6-9 months.

Fish bone meal

(3-16-0)

Marine based alternative to animal bone meal products. Good source of P and calcium with small amount of N. 14% calcium.

Fish emulsion

(5-1-1)

Source of N and micronutrients. Strong fishy odor.

Greensand

Derived from marine deposits, a slow release P and trace mineral fertilizer. Loosens clay soil and increases moisture holding capacity of sandy soils.

Kelp meal

(1-0.1-2)

Slow acting fertilizer of milled seaweed with micronutrients; nutrients-rich.

Langbeinite

(0-0-22)

Neutral pH won’t affect soil pH. Source of soluble potash(K) 22%, sulfur 22% and Magnesium 10.8%.

Manure

Fresh manure is high in salts that can burn plants; use composted manure. Provides macro and micronutrients and conditions soil.

Rock phosphate

(0-3-0)

From soft rock phosphate (colloidal phosphate) – 18% Calcium and long-lasting P. 3% P immediately available, the rest released over 3-5 years.

Seabird guano

(0-11-0)

Source of fast acting P and soil builder. Soil or foliar application.

Soybean meal

(7-1-2)

Plant based slow release N. Can inhibit seed germination if applied during planting. 

Superphosphate

(0-20-0)

Phosphate rock treated with acid to for water solubility. Contains sulfur and calcium.  

Urea

(46-0-0)

Inexpensive, fast acting, concentrated form of N for home gardeners. Good for alkaline soils or acid loving plants as it lowers pH.    

AMENDMENT

DESCRIPTION

Compost

Decayed organic materials, improves soil structure, provides slow-released nutrients. Plant based compost recommended over manure-based compost which is high in salts.

Cover crops

Green manures - grains, grasses or legumes planted to improve soil. Choose warm or cool weather crops; annuals or perennials; nitrogen fixing or non-nitrogen fixing. They suppress weeds and are a food source for pollinators; add nutrients, microbes, organic matter to improve soil structure.

Earthworm castings

A soil conditioner - loosens soil, improves aeration, increases water movement and increase soil organic matter.

Gypsum

Mined calcium sulfate, 20% fast-acting calcium and 15-18% sulfur. Helps clay soils high in sodium (sodic soils) or with a low Ca:Mg ratio. Will not help compacted hardpan clay. Added calcium has no effect on pH.

Manure

High ammonia levels, salts, and may contain pathogens and weed seeds. Do not add fresh manure to growing plants. Do use well-composted or manure aged 6 months. Rabbit, sheep and chicken manure are highest in nutrients.

Mushroom compost

Approx. 2.75-1.5-1.5 - compost used in mushroom farming, can be high in salts. Incorporate and water well before planting. Do not use if soil is high in salts.

Mycorrhizal inoculants

Beneficial soil fungi associated with plant roots, increased water holding capacity, nutrient uptake and defense against pathogens. The fungi do not add nutrients. Most healthy, non-compacted soils contain these fungi, so it does not need to be added. Mycorrhizae is a living organism so many purchased products do not contain viable fungi.

Peat moss

Contains little nutrient value but good soil amendment for sandy soils as it increases water retention. Peat is acidic and will reduce pH of the soil which is helpful when growing acid loving plants like blueberries and azaleas. Do not use as mulch. Dry peat repels water.

Pine needles or shredded bark

An alternative to peat moss that retain moisture. Very acidic.

Sand

Impractical as an amendment as large quantities needed. Adding sand to clay soil will result in a concrete-like soil.

Wood products

Sawdust, ash, wood chips - Do not add as an amendment. These products are high in pH and salts. They will also bind nitrogen in the soil and make it unavailable to plants.