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01-07-2003, 07:20 PM

In article ,
(Greg) wrote:

Everything I read says that bermuda should be kept between 3/4" to 1"
but never does it say why? Is this because of the look or is there a
real reason to mow this short?

Thanks,
Greg

Every plant in the world shows "apical dominance" i.e. hormones are
produced at the top of a plant that inhibits shoots lower down from
developing and thus letting the plant grow vertically and inhibiting the
amount of lateral branching. When you cut off the top of a blade of grass
you take away these hormones and thus encourage lateral branching. For
bermuda this means it will send out more runners and stolons (it is a
creeping grass). For other grasses (bunching) they may send out more
lateral tillers. So when you mow your grass regularly you are
encouraging lateral growth and dense turf. For every grass there is an
optimal height to relieve the apical dominance (and thus encourage lateral
growth). Recommended mowing heights are based on this. If you choose
to grow your grass much longer you will discourage lateral growth and
eventually your turf will become thin. Recommended mowing heights for
bermuda vary from 1/4 inch for some hybrid bermuda grasses so 1-2" for
some common cultivars.

Note it is also recommended that you do not cut off more than 1/3 of the
blade at each mowing. The reason for this is that carbohydrate reserves
are stored in the blade. When you cut the blade the plant tries to
restore this reserve. If you take of less than a 1/3 of the balde the
plant is not shocked. When you take out a lot more the plant responds by
trying to make more leaves at the expense of roots (leaves take precedence
over roots). This weakens the roots. When you have a grass with very low
mowing height you have to mow very frequently to keep the plants in
optimum health (golf courses may mow more than once a day!!!!). So
ideally the grass you grow has a recommended growing height that is
compatible with how frequently you can conveniently mow.

Roland