The most obvious step is
thorough weeding. Next, we can keep the surface fluffed up with a
rotary tiller or hoe during April and May, to break its capillary
connection with deeper soil and accelerate the formation of a dry
dust mulch. Usually, weeding forces us to do this anyway. Also, if
it should rain during summer, we can hoe or rotary till a day or two
later and again help a new dust mulch to develop.
Building Bigger Root Systems
Without irrigation, most of the plant's water supply is obtained by
expansion into new earth that hasn't been desiccated by other
competing roots. Eliminating any obstacles to rapid growth of root
systems is the key to success. So, keep in mind a few facts about
how roots grow and prosper.
The air supply in soil limits or allows root growth. Unlike the
leaves, roots do not perform photosynthesis, breaking down carbon
dioxide gas into atmospheric oxygen and carbon. Yet root cells must
breathe oxygen. This is obtained from the air held in spaces between
soil particles. Many other soil-dwelling life forms from bacteria to
moles compete for this same oxygen. Consequently, soil oxygen levels
are lower than in the atmosphere. A slow exchange of gases does
occur between soil air and free atmosphere, but deeper in the soil
there will inevitably be less oxygen. Different plant species have
varying degrees of root tolerance for lack of oxygen, but they all
stop growing at some depth.
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