As summer turns to autumn, the countryside bursts into a riot of colour in a flamboyant demonstration of the magic of nature.

The harvest is done, the nights are drawing in – but the sun is still shining. The perfect time then for a festival.

The big music events may have come and gone, but it’s not time just yet to pack away the tent and sleeping bag. This weekend sees the launch of a new festival celebrating the arrival of what the poet John Keats called the “season of mists and mellow fruitfulness”.

Septembersong is the pet project of musician brothers Robin and Joe Bennett – the duo who founded the hugely successful Truck Festival in Steventon and its eco-friendly offspring, Wood. The event, which starts today and runs through to Sunday (September 15-17), takes place on the same site as Wood, among the trees and meadows of Braziers Park at Ipsden in the rolling Chilterns near Wallingford, Oxfordshire.

While Wood kicked off the festival season in May, Septembersong brings it to a close – perfectly bookending the summer.

It features an impressive line-up of artists from both sides of the Atlantic, with the emphasis on alternative and country-rock and Americana with a psychedelic edge. They include hugely influential singer-songwriter Robyn Hitchcock, Those Pretty Wrongs – featuring Jody Stephens of Memphis rockers Big Star and Luther Russell; and Brooklyn folk-rockers the Annie Keating Band.

Oxford Mail: Cult singer-songwriter Robyn Hitchcock was signed up after a fortuitous meeting in a London pubCult singer-songwriter Robyn Hitchcock was signed up after a fortuitous meeting in a London pub

Joining them are fellow New Yorker Matthew Caws of alt-rock act Nada Surf, Michele Stodart of The Magic Numbers, Oxford’s own Ralfe Band, California’s RJ McKendree, Northern Ireland’s The Breeze, Oxford’s expansive folk-tinged drone-rock act The Flights of Helios, and many more – including hosts Robin and Joe who play with their country-rock band The Dreaming Spires and with Americana talent Danny George Wilson.

“Part of the reason for doing this is the fun of starting a new thing,” says Robin, taking a break from setting up the festival in its safe, secluded picture-perfect clearing in the woods.

“We also wanted to connect with a different season. While Wood is all about celebrating the spring and start of summer, this marks the end of summer.

“It’s almost on the equinox and follows a long tradition of celebrating this time of year.”

Despite sharing a site with Wood, Robin – who also serves a county and district councillor – says it promises to be a very different event: more grown-up, with a rockier edge and far less focus on family.

Oxford Mail: Truck Festival. Picture by Tim HughesDrummer mike Monaghan with the Ralfe Band. Picture by Tim Hughes

“It’s an offshoot of Wood but is something completely different with a more mystical, psychedelic vibe,” he says. “And because the school term has started, it will be less kid-focussed.

“It is also a chance for us to play more of our music, which has taken a bit of a back seat lately, and to explore the process of songwriting.”

To underline the difference between the two festivals, Septembersong artists will not play on Brazier Park’s wooden stage but undercover, the festival forming a circle in the middle of the site.

“We don’t want the two festivals to feel the same,” says Robin, who together with Joe, launched Wood in 2006 as a greener alternative to Truck Festival, which they started 25 years ago.

Oxford Mail: Michele StodartMichele Stodart

While the brothers no longer run Truck, they are responsible for, arguably, it’s finest area – the Veterans and Virgins stage which programmes new talent and festival favourites. Robin says fans of the stage can expect a similar atmosphere at their latest venture.

He is delighted with the line-up, which features not only many of the brothers’ friends, but – in Jody Stephens, Matthew Caws and Robyn Hitchcock – some of their musical idols too (the latter having been signed up after a fortuitous introduction in a busy London pub).

The Saturday night will culminate in an all-star performance of Neil Young’s classic album Harvest.

Aside from the music there will be interviews with the artists, and talks from music and nature experts including Dr Tom Oliver and Oxford’s ‘Hedgehog’ Hugh Warwick.

Oxford Mail: Annie Keating band with Jamie Dawson on drumsAnnie Keating band will star with The Dreaming Spires' Jamie Dawson on drums

“As well as amazing music and songwriters, we’ll have harmony singing workshops and songs round the campfire, talks and interviews, films and after-hours dancing,” Robin says.

“There will be a feeling of connection with nature. When you are at a festival you are more connected with nature than when you are in your home, and we will celebrate that.”

But more than anything, it promises to be great fun – a chance for one last ‘hurrah’ before winter.

“Both Wood and Septembersong are outside the usual festival calendar, but Wood had perfect weather and it is looking good for this weekend too.

“It’s time for one last festival before winter. I like the idea of doing it at this time of year.

“We have a really interesting line-up and a very special setting. We hope this will be the first of many – so come along and be at the first one!”

Septembersong runs from Friday-Sunday, September 15-17, at Braziers Park, Ipsden, Oxfordshire

Day and weekend tickets from septembersong.info