4 May 1, 2022The Sunday Times
Home
reach maturity and encroach
into neighbouring properties.
Environet will install root
barriers along fences from
about £2,000.
Day treated a house in
Hampshire this year where
the bamboo rhizomes (the
underground part of the stem)
had travelled through two
properties’ gardens and
entered a third property
through its skirting board.
“Our client looked behind
their sofa and said, what the
hell is this plant? Their
floorboards had to be
ripped up. They fought
their insurers to cover the
£10,000 bill.”
Part of the problem is that
in the UK bamboo has not
been placed on the Schedule 9
list of invasive species under
the Wildlife and Countryside
Act 1981, unlike Japanese
knotweed.
“If you look online there’s
an awful lot about Japanese
knotweed but still relatively
little about what to do about
bamboo,” says Richard, who
says the element of the
unknown — waiting to find
what they would discover
lurking under his house —
has been worrying.
“It’s not been a pleasant
process. You just don’t know
what they’re going to find.”invasion. “That would have
sent the internal growth into
spasm. The bamboo was
saying, ‘We’ve got to protect
ourselves and grow more
quickly inside’.”
The repair is costing
£6,000, and Richard’s
insurance company will not
cover it. “They said it’s not
an insurable peril, like
subsidence or flood,” he says.
“It has to be a single
unexpected event. This was a
long-term process so they
didn’t consider it under
accidental damage, which was
disappointing. I considered it
a single event as I had no idea
of it until I saw that shoot. If
something’s happening
underground, how are you
supposed to know?”
The Environet team
crawled underneath the floors
to dig out the roots. They are
treating remnants of the
shoots in the garden with
herbicide and inserting a
plastic membrane barrier to
prevent it from entering the
house again. They will
monitor it for five years.
Day says that bamboo
invasions are on the rise, as
juvenile stands planted 20
years ago — inspired by the
rise of garden makeover
programmes, which promoted
them as privacy screens —But why should
homeowners be frightened of
a subtropical plant that looks
so pretty in our gardens? “It is
potentially more dangerous
than Japanese knotweed,” says
Mat Day, a director of
Environet. “It will force itself
up through skirting boards,
and into cavity walls, where it
creates moisture and
promotes damp. It can
weaken pipes — I have seen
pipes split apart by it. And its
roots can bore through the
mortar in brickwork.”
Day says the bamboo had
been spreading in Richard’s
property for years, but the
removal of it from the
garden last year may have
exacerbated the homediscovered a vast and
insidious network of greenery
taking hold underneath their
home. “The stuff in the living
room was minimal,” Richard
says. “The vast majority was
in the kitchen extension.
We even discovered bamboo
growing behind the washing
machine and tumble dryer.
It likes warmth.
“We never imagined this
was possible. Where it could
come up, it did. It can’t grow
through concrete. It has to
find a void, a weak point. It
will even emerge in a cavity
wall. It chooses the path of
least resistance. It will go
along, along and along. It
will search for light, a gap in
the floorboards.”M
uch has been
written about
the scourge of
Japanese
knotweed, but
there is another menace
lurking in our gardens that
could do even more damage
to our homes — bamboo.
When Richard, a marketing
professional in north London,
bought a terraced house nine
years ago he noticed bamboo
growing in the garden but
didn’t give it a second thought.
He became used to chopping it
back every spring and
summer. Last year, when he
redesigned the garden to give
his children more room to
play, a gardener ripped out
the bamboo. All gone.Or so Richard thought —
little did he know, it was
invading his house.
In January this year, when
his daughter was playing in
the corner of the living room,
she lifted one of her toys and
encountered a strange sight:
a plant sprouting from
beneath the floorboards.
“We could see clearly that
it was bamboo,” Richard, 41,
says. “It’s quite shocking
when you find it. We started
looking between more
floorboards and saw a few
more leaves.”
They hired Environet, a
company that eradicates
bamboo and Japanese
knotweed. The inspectors
combed the house andSPACE
INVADERS
An underground network of
bamboo cost one man £6,000
to remove. By Hugh Graham
Richard with the bamboo growing underneath his house