Spring
Apart from rapidly-lengthening daylight hours, the progression of the flowers, and the gradual migration to warm-weather clothes, today I have encountered a couple of very specific signs of the season.
First, after several hours of rain this morning, I went out in the afternoon. In the damp post-rain air, I suddenly caught the strong whiff of the wild garlic, the first real treat of the year available for foraging. I shall enjoy collecting and eating it over the next few weeks.
Second, I seem to have a nightingale in the back garden. OK it could also be a near neighbour, but on balance of probabilities I think it’s my garden. It’s a noisy bugger, though one of the nicer noises in this or any other place I’ve lived. I’ve just finished my evening meal and was serenaded. Damn, the glass of wine was right, but I should’ve been out on the terrace with a young lady! Alas, I fear for any innocent little bird in a garden where the neighbours both sides have cats.
niq's soapbox 
You’re very fortunate to have a nightingale in your garden this early in April. Generally they arrive in the UK in mid-April and their numbers have been declining due to habitat loss.
A well-targeted hosepipe deals with cats effectively and without causing injury, although cat-loving neighbours may object as many don’t seem to appreciate the harm that felines can do to our wildlife.