The Mother's Moon

The full moon of May is often known as the Flower Moon or Mother's Moon. It is the month where the Earth flourishes. Plants, animals and insects all come into their prime as summer approaches, and the Earth changes from her Maiden form to her Mother form.
The beginning of May is marked by the festival of Beltane or May Day, which celebrates the great marriage between the Earth and her lover to allow this life to flourish.
A lot of plants come into flower this month, hence the moon's other common name. This is explained by another county saying:
April showers bring forth May flowers.

Beating the Bounds

Rogation Sunday, around 25th April, is a little marked date today. It stems from the Latin rogare, meaning 'to move' or 'to ask for.' It involved circulating the parish bounds and asking for a bountiful year. Crosses were carried, along with green boughs to symbolise fertility, and prayers were said at various points, often under an oak tree. Place names with the element Gospel Oak indicate such sites. Crosses were placed at parish corners to physically and spiritually mark the bounds. 
Rogation Day was introduced in the 8th century and was a Christian adaptation of the Roman robigalia, a procession through the cornfields to pray for their preservation. The bounds were beaten to symbolically drive out the devil, presumably into the neighbouring parish.  
It was marked into medieval times and then suppressed for its pagan connotations, but the beating of the bounds ceremony survived into the 19th century. This was a more prosaic adaptation to ensure no boundary stones had been moved or unauthorised buildings erected. The bounds were still beaten, as were boys at strategic points, apparently to ensure they would remember their parish boundaries in years to come.