Greens have welcomed the government’s long-awaited National Pollinator Strategy (NPS) – but are angry that it will not lead to a clamp down on the use of pesticides.

The plan, unveiled by environment secretary Liz Truss, calls on gardeners to let lawns grow longer, and urges councils to plant wildflowers on roadside verges.

It’s aimed at reversing a decline in honey bees and beneficial pollinating insects.

Environmentalists are angry that MPs still won’t clamp down on neonicotinoids – the farm and garden insecticides that campaigners have linked to bee decline.

The Guardian’s environment columnist George Monbiot mocked the NPS. He wrote on Twitter: “Government which fought to ensure that farmers keep spraying countryside with neonicotinoids now says save bees by not mowing your lawn!”

Policy officer at Pesticide Action UK, Nick Mole, welcomed the NPS but said: “We are disappointed that this opportunity to highlight the negative impact that pesticides have on our pollinators has been missed.”

The Bee Coalition, a network of major UK environment organisations, said there was “no planned action on neonicotinoids in the NPS”.

The coalition claims that pollinators contribute £510 million worth of crops to the UK’s economy every year.

They say it would cost the country at least £1.8 billion annually to pollinate crops without bees – an expense that would ramp up the price of households’ weekly shop.

A two-year ban on three neonics is in force across Europe, but other neonic bug sprays remain legal and on sale. The bee coalition says the two-year moratorium is not long enough, and wants it extended and assessed.

Announcing the NPS, environment secretary Liz Truss said: “As much as one third of the food we eat is pollinated by bees – from apples and pears to strawberries and beans.

“That’s why we’re doing everything we can to help them thrive. Not everyone can become a bee-keeper, but everyone from landowners to window-box gardeners can play their part in boosting pollinators,” she added.

Pesticide manufacturers have always denied any link between neonicotinoids and bee decline.