In this week's Fruit of the Land column, CLAIRE APPLEBY reflects on age old signs of the weather.

Early morning walks across the fields have brought to mind two old country weather sayings that seem less accurate this year.

The month has brought some glorious sunrises and sunsets, a reminder of the old aphorism 'Red sky at night, shepherd's delight, red sky in the morning, shepherd's warning'.

The saying dates back at least as far as the bible. The Gospel of Matthew tells us that 'When evening comes, you say, 'It will be fair weather, for the sky is red,' and in the morning, 'Today it will be stormy, for the sky is red and overcast.''

Some versions refer to sailors rather than shepherds, and Shakespeare recognises both in the narrative poem, Venus and Adonis –

Like a red morn, that ever yet betoken'd,

Wreck to the seaman, tempest to the field,

Sorrow to shepherds, woe unto the birds,

Gusts and foul flaws to herdmen and to herds.

There is some logic behind these old sayings. Dust and other small particles are trapped in the atmosphere by high pressure weather systems, and these particles scatter the blue wavelengths, leaving only the light at the red end of the spectrum to paint the sky in beautiful hues of orange, scarlet and pink. Our weather systems come mainly from the west, so if the sky is red at sunset, when the sun is in the west, this means that the high pressure weather system is moving towards us, bringing the promise of fair weather the following day. However, if the sky is red at dawn then the high pressure system has already passed, and will probably be followed by a wet and windy low pressure system.

Another country saying is not running true to form – yet. Well before the blackthorn leaves have emerged, its pure white blossoms are blanketing the bushes' bare black branches to provide a stunning display in all the local hedgerows.

The blossoms often coincide with a spell of cold weather, which is known as a blackthorn winter. Happily, the weather this week is mild and, as I write, there are blue skies and sunshine. But the blackthorn will blossom well into April, so the wintry spell may yet be on its way.