“We have adopted a
plot in a community garden that is filled with mint and
horseradish. How can we get
rid of it without the use of chemicals? Thanks, Karin
Karin and Gus,
This is the right time of
year to tackle your problem. Mint and horseradish are both invasive in
different ways. Both go dormant before winter. Mint spreads laterally;
you need to dig up every bit of the spreading roots. If you use a spading fork
instead of a spade, you will be able to get a hold of and follow the roots without
breaking into pieces (each one of which will be viable). Remove the roots
in long sections if you can.
With horseradish you need to
dig deeper but try to remove the entire root. If you can’t get to all
of the root, remove young plants in the spring as soon as they show themselves until
the root uses itself up. Plants need to photosynthesize to make more food and
grow. Depriving the plant of leaf surface will eventually do it in.
Once you remove the roots
than you can mulch the area to keep other weeds from getting started and to
build soil-energizing humus. One approach is to mix 12 inches or so of “brown”
and “green” organic matter in a 50-50 ratio, the same materials you
would use in a hot compost. Leaves (brown) are easy to obtain this time
of year. Chopped up horseradish leaves (green) and other garden debris can be
used. Espresso outlets will likely be glad to have you take away their grounds (
a “green”). After making sure all the materials are damp, cover
with burlap coffee sacks until spring.
In the spring, remove the
burlap and you will be rewarded with a couple of inches of beautiful weed-free
humus. As you start your new garden, be vigilant for new growth mint and
horseradish. Nip them when you spot them.