Wealden Times | WT184 | June 2017 | Kitchen & Bathroom supplement inside

Garden
War on Weeds
Jo Arnell tackles the trickiest garden invaders
Early summer is the time of maximum growth. The soil
is warm and the danger of frost has passed. Everything
in the garden should be rosy, except that sometimes
it isn’t. One of the main issues that can sap our gardening
enthusiasm are weeds. I am slightly in awe of weeds. They
are such opportunists – tough and persistent, they will grow
almost anywhere and in virtually any soil (if only some of
our cultivated plants were as adaptable). They are also fast
to germinate – always before any cultivated crops - and they
grow so quickly that they easily out-compete other plants
and choke them out, often quite literally. They can be hosts
for diseases and larval stages of pests. It’s also been found that
some actually send out substances that inhibit the growth of
other plants. It is quite obvious that weeds spend their days
plotting to take over the world and mid June is when they
get close to achieving their aim. Understanding a little about
how they manage to be so invasive might prevent you from
getting too demoralised and help you launch a counter-attack.
Broadly speaking weeds are either annuals, perennials or,
occasionally, monstrous invaders like the ubiquitous Japanese
knotweed. Annual weeds grow really fast and set seed early in
the season. Some are called ephemerals, a romantic sounding
word, meaning that they will come and go all through
the year, not just in spring, so that many generations may
germinate within a few months. They are successful because
of the speed at which this happens and by the sheer number
of seeds they disperse each time – thousands from each plant.
The seed can also survive in the ground for years and years.
Annuals seem to be easier to get rid of than perennials, but
every time you disturb the soil you will bring more seeds to
the surface, where they will immediately germinate. Examples
– chickweed, shepherd’s purse, groundsel, hairy bittercress.
Controlling annual weeds
Removal by hand – annuals tend to have shallow roots, so
hand weeding (especially if you can get to them before they
set seed) will be effective. You can dig them up, or better
still, hoe them off. Hoeing will cause less soil disturbance
and therefore less existing weed seeds are brought up to
the surface. Keep the blade of the hoe nice and sharp
so that you can just slice along the top of the soil.
‘No dig’ system – gardening without cultivating the soil
will reduce the amount of disruption in the ground and
will also allow the soil ecosystem to function undisturbed.
A thick mulch applied in early spring, while the soil is still
moist, will help to prevent weed seeds from germinating
145 wealdentimes.co.uk