The warm stretch ends this week, and the weekend arriving behind it is sweater weather with a full calendar: the Island's biggest festival takes over Oyster Bay, Greenport finally gets its rescued Maritime Festival, a world-famous garden opens its gates, and a West Hempstead bakery throws itself a 95th birthday party. Six plans, in rough order of how hard they are to repeat.

Oyster Fest, Oyster Bay. Saturday and Sunday

The 43rd edition of the East Coast's largest waterfront festival fills Theodore Roosevelt Memorial Park and the streets around it with food courts, rides, craft vendors and shucking contests, and the town expects a crowd that can reach 200,000 across the two days. New this year: volunteers are collecting every discarded oyster and clam shell so the empties can be cured and planted back in the harbor as reef for the next generation of shellfish. Your lunch is habitat. Full details in our Oyster Fest preview.

The Oudolf Garden opens at Planting Fields. Saturday

Piet Oudolf, the planting designer behind Manhattan's High Line, opens his first new public garden in New York in more than a decade on Saturday: one acre, more than 24,000 plants, built around a restored Rose Arbor that has stood at the Oyster Bay estate since about 1906. October is when his gardens look their best, all grasses and gold, so week one is genuinely the right week. We wrote about the garden here.

Greenport Maritime Festival. Friday through Sunday

Paused by its longtime organizer last fall, rescued by the village's business community over the winter, and bumped off its September dates by a nor'easter, the 36th Maritime Festival finally sails: a maritime parade, a work boat race, sea shanties and a porgy filleting record attempt, spread across Mitchell Park, the harbor and the village streets. After the year this festival had, showing up is half the point. The full story of its rescue is here.

Mineola Fall Festival. Saturday and Sunday

The village takes over Memorial Park on Marcellus Road both days from noon to 6, and admission is free. It is the small-festival counterprogramming to Oyster Bay: no six-figure crowd, no parking odyssey, just a village park in full autumn mode. If the forecast turns, it moves to October 24 and 25.

Riesterer's Bakery turns 95, West Hempstead. Sunday

Long Island's oldest bakery marks 95 years of continuous family baking with a party at its Hempstead Avenue shop on Sunday from 10 a.m. to 2 p.m.: a classic car show out front, a bounce house and coloring contest for kids, music and giveaways. It is free and open to everyone, and parties like this come around once a generation. The bakery's whole 95-year story is here.

Port Washington Restaurant Week starts Sunday

Seventeen restaurants from Main Street to the waterfront begin eight days of prix fixe menus on Sunday, each kitchen setting its own three-course dinner and many adding lunch. It is the rare event on this list that improves on a weeknight, when tables are easier, but Sunday is opening night. Our guide to how the week works is here.

The honest ranking

If you can only do one thing: the Oudolf Garden on Saturday morning before the crowds find it, then Oyster Fest in the afternoon, since both sit in Oyster Bay and the garden will still be there when the festival's 200,000 visitors have gone home. Greenport is the pick for anyone who would rather drive east than fight for parking on the North Shore, and Sunday belongs to cake in West Hempstead.