Q & A: Sawdust in the Garden?
I spend as much time tending plants in the garden as making sawdust in my
shop.Are there any problems with using the sawdust and chips in my dust-collector
bag as mulch in the garden?
Go for it! A one- to 2-in.-thick
layer of shavings and sawdust is excellent
mulch. It holds moisture well,
keeps down the soil temperature and
prevents weeds from sprouting.Cedar,
walnut and treated lumber, however,
contain chemicals that plants don’t like,
so avoid putting their chips or sawdust
on the garden.
Contrary to popular belief, sawdust
mulch will not leach nitrogen from the
soil (and turn your plants a sickly yellow)
as long as the mulch is left alone
on the surface of your garden. It’s true
that the microbes feasting on your shop
waste will seek an additional source of
nitrogen to flourish,but they won’t rob
much nitrogen from the soil below if
the mulch above is a separate layer.
However, if you mix your sawdust with
compost or dirt,or turn over last year’s
layer of mulch into the dirt around
your plants, add some high nitrogen
(21-0-0) fertilizer to prevent nitrogen
This story originally appeared in American Woodworker February 2002, issue #92.