Winter is around the corner, but Louis Vuitton still managed to throw a garden party Tuesday night at Saks Fifth Avenue. The French luxury firm transformed the store’s third floor into an indoor menagerie, dubbed Les Jardin Louis Vuitton and flooded with magnolia leaves and box hedges. Insouciant models dressed in Vuitton’s new resort collection picnicked (or at least pretended to) at the nexus of the fete. While craftsmen monogrammed Vuitton goods, debonair male model types hung guests’ paper notes on a wishing tree. Some were hoping for Vuitton handbags, others for world peace. “I’m wishing to win the French Open, do you think that’s a good one?” asked Serena Wiliams, mingling among guests such as Arlenis Sosa, Lisa Airan and Annie Churchhill. Co-host Maggie Gylenhaal wasn’t exactly in her element in the garden, she said, but her husband Peter Sarsgaard would have been in heaven. “We have a backyard since we're in Brooklyn and he's developed quite the green thumb,” she said. “But honestly, I couldn't tell.