Gardening is a favourite pastime for millions of Brits, but while it helps us get closer to nature, could plant pots actually be damaging the environment?

As many as half a billion plastic plant pots could be ending up in landfill or incineration every year in the UK alone, according to a new study by the magazine Horticulture Week.

This is because councils don’t routinely recycle them despite guidelines suggesting all pots, except black plastic ones – which are non-recyclable – should be collected.

The magazine asked a sample of 75 UK councils, out of more than 400, and only a fraction – nine of them – said they recycled plant pots.

Most plastics are recyclable but black plastic, as HuffPost UK has reported, gains its colour by being dyed with carbon black pigments and the end result can’t be easily recycled in the UK.

As well as plant pots, an estimated 1.3 billion black plastic trays are used in ready meal packaging in the UK every year and according to Greenpeace UK, with most of those end up in landfill or the ocean because the material is difficult to recycle.