"Weed control is my number one focus," he said.
"I can't emphasis enough what a major threat weeds are to a restoration project like this if left uncontrolled.
"If I didn't keep at it, I reckon the area would be devastated within five years."
He had battled a number of ecological weeds over the years, including old man's beard, blackberry, gorse, willows, barberry, wilding pines and reed sweet grass, otherwise known as Glyceria maxima.
Glyceria at the wetland's edges, he said, was particularly hard to tackle, forming a smothering mat before spreading underground and preventing rushes and other natives from emerging naturally.
In 2003, the Booths' land was accepted for covenanting with the Queen Elizabeth II (QEII) National Trust 2003, a registered charity that partners with private landowners to help them permanently protect special natural and cultural heritage sites.
Mr Booth said the area was a breeding ground for dab chicks and a habitat for shags and the royal spoonbill.
As a result, the QEII Community Weedbusters Project (QEII CWP) had supplied weed spray to help Mr Booth control the weed issues.
The QEII CWP, a national interagency programme launched in 2003, is supported by divisions including Department of Conservation and Ministry for Primary Industries.
Project spokesman Mike Urlich said Kapiti locals and passers-by had loved watching the wetland's evolution over the years.
"The Booths' wetland is an amazing visual gift to the community, and a haven for water fowl as well," Mr Urlich said.
"We are very happy to be able to support this inspirational restoration project."