Study shows native plants can help boost crop yields

Test plantings for the Plant and Food Research study.
Test plantings for the Plant and Food Research study. Photo credit: Supplied / Plant and Food Research

By Hugo Cameron of RNZ

New research shows fruit and vegetable growers can utilise native bush to increase yields and protect plants from pests.

The Plant and Food Research study found having more native plants near crops could attract insects that help with pollination and combat some harmful pests.

Figures from the Ministry for Primary Industries showed insect-pollinated crops such as kiwifruit and avocados were worth about $2 billion to the national economy.

Co-author of the study Dr Melanie Davidson said more farmers were starting to restore native flora and this research showed they would be rewarded for their efforts.

"What it means for farmers is that with the improved pollination you can increase your yield but also you're increasing the resilience of your system because you're not just relying on your potentially managed honeybees that a lot of farmers bring in," Dr Davidson said.

Plantings could attract "alternative pollinators" such as native bees and flies, which can pollinate crops when honeybees are dormant.

"So what that does is it ensures that when your honeybees are not necessarily flying around - because they don't tend to like cooler temperatures or overcast weather - you'll have these alternative pollinators out and about doing the job too," Davidson said.

Some of those alternative pollinators were "natural enemies" of pests that damage crops, meaning having them around would also help control unwanted bug populations, she said.

Further research was needed to find out the best species to plant in different regions and over what sized area.

"On the Canterbury plains for example, we've got less than 5 percent of the plains that's below 300 metres above sea level has any native bush on it. This absence of habitat means that we don't actually know what we're missing until we get it back out there," Davidson said.

The Foundation for Arable Research had biodiversity resources for arable farmers in Canterbury and other projects were in development to share information for other sectors nationwide, she said.