The move follows the publication of a study from University of Sussex's Professor Dave Goulson earlier this year which claimed to have found 'bee-friendly' plants for sale with traces of one of the three neonicotinoid-based insecticide products banned by the EU (imidacloprid, thiamethoxam or clothianidin).
The RHS 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.
"One of the biggest problems for pollinators is lack of flowering plants and the Perfect for Pollinators logo has been helping many thousands of people across the UK to select and grow more of these vital plants in their gardens and outside spaces. Our aim has always been to significantly increase the number of flowering plants available to pollinators.
"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. For anyone concerned about the research we have created a list of organic nurseries.
"The Perfect for Pollinator logo represents plants to grow in gardens that provide valuable resources for pollinators, but it cannot speak for the way in which each individual plant is grown. The RHS is 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.
"One of the RHS’s key objectives is to help gardeners to garden responsibly and grow more plants; for instance, we promote non-chemical means of control for gardeners and provide extensive advice on alternatives to pesticides. We are currently involved in further research projects to provide evidence of the benefits of certain plants for pollinators. We also continue to work with industry and government to support pollinators through the National Pollinator Strategy.
"Ultimately we believe it is better for pollinators that gardens are crammed full of plants that are perfect for pollinators than with no plants or plants without flowers. However, 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."
EFSA’s updated risk assessments on the potential risks to bees from neonicotinoid pesticides will be finalised in February 2018.
The assessments for clothianidin, imidacloprid and thiamethoxam will be finalised following a final round of consultation with pesticide experts in the Member States.
An EC vote on a ban is due on 12/13 December. The vote will be on extending the existing restrictions to all crops and whether to make the existing temporary ban permanent.
However, the EC may wait till the EFSA report is out, which means it is likely to be published a few weeks later – possibly in March.
Jose Tarazona, head of EFSA’s Pesticides Unit, said: "This has been a very complex process. Our call for data generated a very large volume of additional information, which we have considered carefully.
"Additional elements were raised during the consultation with experts from the Member States, and we now want to make sure that these partners have the opportunity to look at the revised assessments before finalising our conclusions."
The European Commission imposed restrictions on the use of clothianidin, imidacloprid and thiamethoxam in 2013 following earlier risk assessments carred out by EFSA.