Lankan potting mix sprouts pest weeds

The Ministry of Agriculture and Forestry's biosecurity arm (MAFBNZ) has identified 15 new-to-New Zealand weeds after contaminated coconut fibre was used to make potting mix.

MAFBNZ environmental response senior adviser Megan Sarty said the fibre, also known as coco peat or coir fibre, was imported from Sri Lanka in October last year. It was made into a variety of potting mixes and on-sold to around 70 nurseries, plant propagators and growers, mainly in the North Island.

Sarty said MAFBNZ was working closely with the nursery and gardening industry to limit distribution of the fibre. Approximately 15 new weeds had been identified as a result of the contamination, she said. "Work is continuing to analyse any potential risk they may pose to New Zealand's environment or primary industries."

The nursery and garden industry was helping to trace where the product had gone, to recover unused mixes and treat potentially affected plants, she said. MAFBNZ will now require all imported coir fibre to be heat treated.

"This is an interim measure until longer term management options for this product are assessed," Sarty said.

NZPA