My records from the last 5 years show the butterfly season running from March to November.
Butterflies are seen on sunny days; not on overcast ones generally.
The peak month is August when I can expect a number of butterflies in my garden every day provided that it's sunny.
Butterfly visits are not predictable outside of the 'British school summer holidays'.
The earliest date in the calendar that I've seen live butterflies is March 7.
I expect 2-3 sightings of butterflies in my garden during March. These have always been the butterfly species that have been in hibernation over the winter.
Your chances of watching butterflies are better in the English countryside than in a town garden during June; the Meadow Brown butterfly is reputed to be the commonest in the countryside.
In my garden, I will be watching for a Large Skipper butterfly.
Even in July, when quite a number of species are in flight, I have noted sunny days in the garden and zero butterflies. Sightings are still sporadic until the last week of the month usually.
As the school summer holidays begin at the end of July, the butterflies arrive in quantity in my garden on sunny days.
The beginning of August is when I have recorded the greatest number of species. The Buddleias will attract members of the Nymphalidae family: Small Tortoiseshell, Peacock, Painted Lady, Red Admiral and Comma.
I expect to have a few sightings of Brimstone butterflies, usually visiting Buddleia, during August.
Gatekeepers are more interested in Field Scabious, Marjoram and Hyssop than Buddleia.
Towards the end of August or at the start of September, will be the day when the garden contains the greatest number of butterflies; most of them will be Small Tortoiseshells. The peak day in 2003 was Sunday 24 August when there were approximately 20 butterflies in both back and front gardens (a total of 40).
My final recorded sighting was on November 15.
Over the winter of 2003 to 2004, I received several emails about hibernating butterflies found in homes and offices. A Painted Lady was reported in Hampshire.