So, , , , you haven't gotten
around to mulching your plants?
I read from time to time that it is
important to mulch the desert soil.
I want to tell you that I think the word important is not delivered
to you in strong enough terms by the authors.
I would like to rewrite that sentence here and offer an explanation.
It is absolutely
necessary to mulch plants
in the desert
You are wasting your money buying plants if you think they can
do well, or in many cases even survive, if you are not mulching
them immediately after planting, especially in the drying heat
of summer. After you have transplanted and watered your
new plants the sun is right behind you to heat-up the bare soil
and pull out the water within a couple of hours. Go stand
in the yard naked after a shower and tell me how long it takes
you to dry-out and heat-up. Lets get real here . .
. you HAVE to cover the soil out as wide as the mature
canopy of the plant or tree will grow.
Mulch can be anything that covers the soil. I've seen people
use carpet under the canopy of their trees, some use rocks and
wood such as shredded cedar or redwood (shredded because it doesn't
tend to blow away like wood chips or bark). In flower beds
I use alyssum and intense planting. In veggie beds I use
silver reflective plastic.
What is mulch? If you lay down on the soil
you are mulch, simply because you are covering the soil.
You are protecting it from drying out and heating up and protecting
the roots from the same disaster. Don't lay there to long
or you will become compost.
I know you think that the roots will go way down to get moisture
and nutrients, but this is not usually the case in our desert
gardens. Some trees will develop a tap root but, if the
tree was grown in a nursery can it is unlikely it will ever grow
a tap root. Many feeder roots grow in the top few inches
of the soil and grow in a wide circle out from the tree.
This is why it's important to keep the moisture from evaporating
by mulching the soil.
Another kind of Mulch
Some bags in the nursery are labeled Composted Mulch.
This stuff is meant to be dug into and mixed with native
dirt to provide tilth, nutrients and microbes to the soil. Plant
roots like this environment, they can move easily to get the nutrients.
It's important to use this while it is fresh and new and moist
to take advantage of its full potential.
Don't use wood chips/bark or shredded wood to mulch flower or
veggie beds. The reason for this is that it can get mixed
into the soil where it will start to decompose. This process
of decomposing takes the nitrogen away from your plants and they
will have great difficulty growing. They just sort of sit
there, staying little, week after week, because the nitrogen they
need is being used by the wood.
On veggie beds I use plastic 'silver reflective mulch' with drip
irrigation underneath. In flower beds I plant lots of herbs
and use a 'living mulch', like alyssum, to draw the pollinating
insects I need for my fruit trees and veggies. Also, planting
a variety of 'annuals' intensely (real close together) acts like
a mulch as they will grow to shade the soil. This is good
under the canopy of trees and it's also very pretty. I planted
my petunias 6 inches apart. Confession: As I began to run
out of petunias they went in 8 - 12" apart, but the newly
sprouting alyssum will fill in the spaces, , and it is becoming
very fragrant around here. (Alyssum re-seeds itself every
year and mostly comes back white.)
When you purchase composted mulch to mix with your soil, make
sure there are no pieces of wood in it. If there are, it is not
fully composted and it can (probably will) rob your plants of
needed nitrogen.