mulch madness

the plant scientist in me gets a little bugged out each spring, just as much as my graphic designer friend gets bugged out by people who use comic sans ms.

why, you ask?!?

mulch. madness.  get it.  march madness, but with mulch. bahaha. (yes, there is one more hour left in march...i gotta type fast.)

alright.  someone get me a paper bag, i'm about to have myself a panic attack.

pleeeease someone make it stop!!  it hurts to look at them.

if you read this and you are guilty of this terrible horticultural crime, turn yourself in.

just don't tell me you are using red mulch.  i'll really lose it.

as part of your intervention, you need to know what happens when you add a ridiculous amount of mulch to a tree trunk.

it will kill your tree...eventually.

would you like some shrub with your mulch?

it is a leading cause of death of azalea, rhododendron, dogwood, boxwood, mountain laurel, hollies, cherry trees, ash, birch, linden, spruce, and many other landscape plants.

oxygen starvation.  roots need oxygen.  if oxygen level dips under 10%, roots will die.  foliage will show chlorosis (yellowing), minimal new growth, dieback of older branches.

inner bark death.  you know those roots that grow stems separate from the rest of the tree?  the tissue is much different from that of roots.  it does not do well when moisture is present for a lengthy amount of time.  same with the tissue of the inner bark.  the phloem (c'mon folks, dust off those ol' biology textbooks) of the inner bark dies.  not immediately, but over years.  

disease and insects.  the bark of a tree is there to protect against invaders.  flies are to poop, as casual agents are to weak plants.  fungus, bacteria, and insects will gain foothold of a moist, decaying bark.  

excess heat.  moist mulch will have the same effect as composting during the warmer months.  if the temperature reaches between 120 and 140 F, it may kill the inner phloem of trees, especially young trees.  during the hardening-off period, in the fall, when trees get ready for winter, the warm mulch may prevent the roots from becoming adjusted to the colder weather.  resulting in root death.  

have i turned you into a mulch snob, yet?  i hope so, we need more of me in the horticultural world.  (not to toot my own horn or anything:)

we've got the what and why...here's the how.

rule of thumb says:

mulch should not exceed 3 inches deep.

3 to 5 inches away from young plants.

8 to 12 inches away from mature tree trunks.

when they say "volcano," you say "donut."  "volcano"  "donut" "volcano" "donut."

here's the fact sheet from my alma mater.  it goes into more detail. knowledge is power, my friends.  

if your trees have fallen victim to mulch volcanoes and i have just scared the bejesus out of you, don't worry, there is still hope for your trees.  take a rake a gently pull back excess mulch.  be sure not to damage roots.  you may do this a few times during the few growing seasons.  just don't go crazy.  digging out the old, excess mulch may do more harm than good.  

hope this helps...or humors you.

g'night.

jill