From the Royal Horticultural Society

The proportion of front gardens that are planted rather than paved has increased dramatically in recent years but there is still much to be done
Front garden greenery has grown by an area 70 times the size of Hyde Park since 2015, our research shows.
This increase in front garden plant cover is expected to be bringing far-ranging benefits to people’s health and wellbeing, to the environment and to wildlife.
Using results of an RHS survey of 2,056 UK adults carried out by YouGov and data from a 2015 survey carried out by Ipsos Mori, the RHS has found that plant cover in front gardens has increased by almost 40 sq miles (25,600 acres) in just five years, from 164 sq miles (105,000 acres) in 2015 to 202 sq miles (129,000 acres) today.
More than one million more UK front gardens contain nothing but greenery and the number of front gardens containing no plants at all has halved.
Greening Great Britain
However, with more than a third of front gardens containing less than a quarter plant cover, and 2.5 million with no plants at all, there is still critical work to do to unlock the true potential of UK gardens and green spaces.
RHS Director of Science, Professor Alistair Griffiths said:
“The RHS has been promoting the importance of adding plants to paved over front gardens since 2015 when we launched our Greening Great Britain campaign.
“Although there is still much to do we are thrilled to see an improvement which has been helped by millions of people taking up gardening over lockdown and buying more plants to grow indoors and out.
“RHS science suggests that this substantial increase in greenery will be bringing wide-reaching benefits to people’s mental and physical health and to wildlife; improving air quality, helping conserve water from rainfall and cooling cities in hot summer months.”
Wales (3%) and the south west of England (5%) have fewer paved-over front gardens than any other region. Wales (38%) followed by Scotland (34%) and the south west of England (32%) have the greenest front gardens.