How do I know? Well, apart from the date on the calendar (only three more weeks and the roads will be clogged up with the school run again), there are warblers in the garden.
On several occasions in the past week, there have been four Willow Warblers around simultaneously. They seem to be feeding up: flitting around in the buddleia, onto the ground, into the flowerbeds and even for a quick drink at the pond. I wonder if they're locally-bred siblings or if they're passing through and we're actually seeing different birds every day?
In addition to the WWs, at least two different Blackcaps have been seen: a female-type and what looks like a very dull, dark brown-capped youngster (I think it could be a young male). The first bird sampled some Woody Nightshade berries before going back to the Honeysuckle; the other bird also seems to prefer shiny Honeysuckle berries and swallows them whole. A Whitethroat has been seen, too.
Now's the time of year when we could get something weird turning up - perhaps a Reed Warbler like last year, though obviously a Sedge would go down well for the garden list. Lesser Whitethroat would be welcome, too, or even a Pied Flycatcher or Redstart. Well, I can dream.