HEAVY falls of snow and freezing temperatures are about to plunge Scotland back in to winter – a month after the start of British Summertime.

The Met Office last night flashed yellow “be aware” warnings of severe weather affecting the Highlands, Western Isles, Grampian, Tayside, Fife and Central.

Motorists on northern trunk roads face white-out conditions as a blanket of freezing air from the Arctic washes over the country.

One of Scotland’s leading gardening experts has warned amateur enthusiasts to take action to protect plants as temperatures drop as low as -5C by Wednesday.

The cold snap will feel all the more shocking as the country has been basking in higher-than average temperatures for April, including sunshine over the weekend.

Emma Boorman of the Met Office said: “This is one last hurrah from winter. There could be some really nasty conditions on the higher trunk roads. Heavy snow will arrive in the early hours of [today], lasting for most of the morning.

“Things improve later as the sun comes up and the wintry conditions battle against the heat of the sun.”

By Wednesday, the Mercury could fall as low as Minus 5 Celsius (23F).

George Anderson, presenter of the BBC’s Beechgrove Garden, says plant damage usually begins when temperatures drop to -2C. However, damage is more pronounced the longer plants have had time to grow, which makes them “softer”.

He said: “We had an air frost about 10 days ago and I have noticed some things in my garden – like young foliage – which has been frosted.

“People don’t notice the damage taking place and you later wonder why leaves are distorted. If things do go as low as -5C then it will be bad news for plants.”