Get them before they start... Weeds
compete with garden plants for nutrients, space, and sunlight. Weeds
can make your otherwise tidy organic garden appear scraggly, and
weeds harbor insect pests that carry diseases. The best way to
control weeds without chemical herbicides is to prevent them from
establishing themselves in your garden.
Mulch
Adding a 3-inch layer of organic mulch is one of the best methods
you can use to prevent weeds. Mulch prevents sunlight from reaching
weed seeds, preventing them from germinating. Mulch retains moisture
in the soil and keeps it from compacting, so that you can easily
pull young weeds as they sprout.
You can choose bagged wood chips or shredded bark for your garden
mulch, but compost makes excellent mulch. If you use compost or
other finely textured mulch like grass clippings, replace it as
frequently as once a month, as it breaks down quickly.
Before Digging
If you’re preparing to dig or till a new plot of exposed earth,
devote a day to removing as many weeds as possible first. Many
perennial weeds, like bindweed and thistle, spread by means of
rhizomes or creeping stems. If you leave root segments behind, your
tiller could distribute these viable plant parts throughout your
garden, multiplying your weed problem a hundredfold.
Solarize Your Soil
You can make the greenhouse effect work for you by baking weeds and
their seeds in situ, before you plant a barren plot. In the summer,
cut all existing weeds to ground level. Water the area thoroughly,
lay a sheet of clear plastic over the entire plot. Old shower
curtain liners work well for this chore. Pin the plastic down with
metal u-shaped stakes so the wind doesn’t move the plastic sheets.
If you use a single large sheet, weigh the center portion down with
rocks to prevent cooling air pockets from forming.
After 8-10 weeks, the sun’s radiant energy will have sufficiently
raised the temperature of the soil so that all weeds and seeds are
no longer viable. As an added benefit, solarization kills many
soil-borne diseases and pests. Your organic plot is now ready for a
fall planting of cool weather vegetables.