The Royal Horticultural Society is reviewing its Perfect for Pollinators labelling initiative in the light of research that showed plants in garden centres contained pesticides that could harm pollinating insects.

An RHS statement said: “We care passionately about a healthy future for our bees and other pollinators, which is why we created the 'Perfect for Pollinators' logo – to help people select the best plants to support these important insects.

“However, we have been reviewing this initiative following a study of UK garden centre plants, which revealed that some plants carrying the pollinator friendly label contained traces of pesticides.”

The RHS says it cannot monitor the way in which each individual plant is grown all garden centres. “We are a charity and cannot possibly police how hundreds of thousands of plants are grown within the horticultural trade, in the UK and across Europe, before the point of sale. We are, therefore, considering the future of the logo and whether we should withdraw it from the market.”

“We need more time to continue to explore options for the 'Perfect for Pollinators' logo to make the best decision for our precious bees and other pollinators. We want to continue to promote the planting of flowering plants for bees and other pollinators and are working towards the best route to do this practically.”

The Garden Organic organisation, on its website, recommends the following top ten plants as helpful to pollinators and other beneficial insects:

Buddleja

Comfrey

Cowslip

Common poppy

Cornflower

Fennel

Foxglove

Forget-me-not

Greater knapweed

Ivy

Lavender.

They mention that certain weeds – such as thistle and dandelion – are also helpful - - the latter providing an important source of nectar early in the year for insects.