How to do I get rid of clubroot? I do raised-bed gardening and every
year I get clubroot in at least one of the beds. I get it with just
about everything including radish, cabbage, broccoli, cauliflower,
and kohlrabi. I get rid of it in one bed, then it shows up in
another. Thanks for your help!
A. Clubroot is a disease
that only affects members of the cabbage family including cabbage,
broccoli, cauliflower, Brussels sprouts, and kohlrabi. The disease is
called clubroot because it causes the plant's roots to swell
abnormally into a large, club-like, misshapen growth. Because the
swollen roots are under the soil's surface you can't see clubroot
until you pull up the plant, but there are other symptoms.
Visible symptoms include wilting during the daytime
and the outer leaves turning yellow and falling off. The plant slows
down and dies.
Clubroot is caused by a soil-borne fungus that lives
in the soil for years. Acidic soil along with warm, moist weather
helps this disease to spread. In the roots the fungus causes cells to
grow and multiply which results in a swollen root system. The plant
is weakened and susceptible to infection from other diseases that
cause root rot. The disease spreads into the soil around the rotting roots.
There is no cure for clubroot. Infected plants should
There are a couple of preventative measures you can
take to lessen the effects of clubroot in future years. Practicing
crop rotation by not growing members of the cabbage family in the
same spot for seven years will help. Also, raising the soil pH to 7.2
by adding ground limestone will discourage the infection.