Whatever happens above the soil level, directly affects what happens below the soil level and vice versa.

Proper mulching is so important that there is actually an ANSI standard for it.

What is ANSI? The American National Standards Institute (or ANSI) is a non-profit organization that oversees standards and conformity in the U.S. that help assure the safety and health of consumers and the environment. 

Some key points:

– Mulch should be between 2-4 inches deep

– Synthetics, crushed stone and volcanic rock are not considered mulch

– Fabrics, weed cloth, impervious plastic sheeting are not to be used under mulch.

A healthy root system requires soil with adequate gas exchange. It’s as important as water. Anything that impedes that gas exchange is detrimental to your trees and plants. That’s why it’s best to forego pervious fabrics too.

Benefits of Mulch

– Moderates soil temperature

– Lowers pH

– Reduces salt buildup

– Source of organic matter

– Improves fertility

– Reduces compaction

– Suppresses weeds

– Reduces reflection which helps retain moisture

– Reduces competition with turf

– Decreases disease

Are you familiar with mycorrhiza? Mycorrhiza is the symbiotic or mutualistic relationship between fungi and the roots of plants. The benefits of healthy mycorrhiza are innumerable, everything from increased drought and pathogen resistance to enhanced vigor and growth. Mulch promotes healthy mycorrhiza which in turn promotes healthy plants!

And remember, don’t mulch too close to your tree trunk. Keep your root flare (the area where trunk meets roots) visible. If you’re not sure, a good rule of thumb it to keep mulch one foot away from the trunk.