Compost: A Natural Cycle 
Composting is a natural process in which micro-
organisms and macro-organisms break down organic 
material (leaves, twigs, grass, etc.) into a dark crum -
bly soil amendment.  Modern compost facilities use 
the same natural biological composting process.  
Their controlled-temperature process works faster, 
breaks down pesticide residues, and also kills weed 
seeds and plant diseases.
Compost improves soil structure and plant 
growth by
•  Replenishing soil organic matter, and storing          
   nutrients in plant-available forms
•  Supporting beneficial soil life
•  Reducing erosion and water run-off
•  Loosening clay soils for better root    
   development (increasing soil pore space)
•  Retaining moisture in sandy soils so    
   plants need less watering.
Comparing Landscape Products
A variety of soil and landscape products are sold.  Here’s a 
comparison:
Compost is stable, decomposed organic matter, excellent for 
improving soil structure, fertility, moisture holding capacity, and 
plant growth.
Mulch is any material applied to the soil surface.  Woody mulches 
(high in carbon, low in nitrogen) like wood chips, bark and woody 
composts are great for woody plants.  Annual plants should be 
mulched with nutrient-balanced mulches like compost, grass 
clippings, or leaves.
Peat Moss is partially decayed sphagnum moss from peat bogs.  It 
provides soil porosity, but not the nutrients or biological diversity for 
healthy soil that compost provides.
Fertilizers are concentrated sources of plant nutrients, used in small 
amounts to supplement natural soil fertility.  
Topsoil that is sold is usually not native topsoil.  Quality 
manufactured topsoils are a blend of native sandy sub-soils with 
composted organic matter to support soil life.
Ask Your Compost Supplier
Whether you’re buying direct from the composting facility, or from a local  
 vendor, here are some good questions to ask:
	 •	 What	 ingredients	go	into	your	compost?
	 •	 What	 compost	products	or	blends	do	you	sell?
	 •	 Are	 there	quality	control	or	testing	results	available	for	these		 	
	 	 products?	 (These	may	be	on	the	manufacturer’s	website.)
	 •	 Which	 product	is	best	for	my	intended	use?
	 •	 What	 application	rate	do	you	recommend?	
	 			•	 How	much	do	I	need	for	my	area?		(Or	see	pages	4-6.)