The best thing happening in Boca this Saturday costs nothing, and you still cannot just show up for it. The International Coastal Cleanup at Spanish River Park caps its volunteer list, registration opened back on August 1, and the only way in is a phone call. That is the weekend in miniature: a couple of the good things need a plan, the rest you can walk into. Here is how September 18 to 20 lays out across Delray, Boynton and Boca, with the details that actually change whether you have a good time.

☕ Morning: the seed. on Atlantic Ave

Order the açaí and it arrives inside a hollowed pineapple. That is not a garnish decision, it is the house move, written into the shop's own sustainability mission right next to the reusable tumbler program, and it is why half of Atlantic Avenue has a photo of one. The pitaya bowls come the same way.

the seed. has been family owned since 2014, with shops in Boca Raton, Lighthouse Point, Boynton Beach, and this one at 526 E Atlantic. It is small: a handful of seats inside, a few outside, and a bench swing on the sidewalk that people actually wait for. Regulars go for the breakfast burrito or the cinnamon roll alongside whatever espresso drink they are on that month, and the seasonal board rotates hard enough that it is worth reading before you default to your usual.

The timing matters here. They open at 8 AM on weekends and close at 5 PM, so if you are doing the beach cleanup you are not squeezing this in beforehand. Go after, when the cleanup wraps at 11.

🍕 Lunch: Sole Mio Kitchen & Bar, Boynton

If you knew this place as Nicoletta's, it is the same kitchen and the same family under a new name. What changed is the menu, which got longer and considerably more serious.

The pizza is the reason to drive out to Canyon Town Plaza. They mill their own flour, cold-ferment the dough for 24 hours and the focaccia for 48, then hand-toss it New York style. The Hot Honey Pepperoni is the order: pepperoni, mozzarella, Calabrian chili and a hot honey drizzle, with the heat landing right behind the sweet instead of on top of it. If you want the pie that shows off the kitchen, the Truffle Funghi comes with wild mushrooms, ricotta and thyme, and there is a White Clam Pie built on garlic olive oil with lemon and parsley. Sizes run from a 12 inch up to an 18, plus a Sicilian and a gluten-free crust.

On the pasta side it is the Italian-American canon done properly: Nonna's Lasagna, Spaghetti and Meatballs, Penne alla Vodka, Carbonara, and a Braised Short Rib Pappardelle in red-wine tomato sugo that is the best argument on the menu for skipping pizza entirely. Chicken, veal and shrimp all come Parmigiana, Francese, Piccata, Marsala or Milanese. The seafood list goes deeper than you expect from a pizza place, with a pan-seared Branzino and a Lobster Fra Diavolo over linguine.

Two insider moves. Their own menu points out that the 14 inch gives you roughly 40 percent more pizza than the 12 for a couple of dollars more, so size up. And if you can push the meal to dinner instead of lunch, they are running a three course prix fixe all September, evenings and dine-in only, with nine mains to choose from before upgrades. One thing to know before the check lands: they encourage cash and add 3 percent on credit card transactions.

They open at 11 every day but Monday, and stay open until 10 on Friday and Saturday. Parking is free.

🌊 Saturday morning: International Coastal Cleanup, Spanish River Park

This is the one to plan around, and it is also the one most weekend guides get wrong.

The cleanup runs 8 to 11 AM on Saturday, September 19, at Spanish River Park, 3001 N Ocean Blvd. You work the beach and the Intracoastal mangrove habitats, and you log what you pull out using the Clean Swell app so it feeds Ocean Conservancy's global data set. Gumbo Limbo Nature Center manages the Boca site. There are free tee shirts while they last, and community service hours are available, which is worth knowing if you have a high schooler who needs them.

Now the part the flyers bury. Registration is required and space is limited. It opened August 1 and you reserve by calling 561-544-8612. There are no walk-ups, and the Spanish River site has filled up in past years. Children and teens under 18 have to participate with a registered parent or guardian, so no drop-offs.

One more thing the flyers skip. The cleanup itself is free, but Spanish River is a paid beach park and standard weekend entrance fees apply without a permit. Ask about volunteer parking instructions or waivers when you call to register. It is one question on a phone call you are already making, and it is worth asking before you pull up to the gate.

The event is subject to cancellation for weather.

🎷 Saturday night: Hendrik Meurkens Samba Jazz Quartet, Arts Garage

Meurkens leads a band on two instruments most jazz rooms never hear out front: harmonica and vibraphone. He started on vibes in Germany, then at 19 heard Toots Thielemans play harmonica and redirected his whole career around it. He has been in New York since 1992, has 30 albums out, and has recorded with Ray Brown, Paquito D'Rivera, Astrud Gilberto and Monty Alexander.

Saturday's show celebrates his new record, Samba Tonto. The quartet is Mike Eckroth on piano, Jamie Ousley on bass and Ludwig Afonso on drums, and what you get is Brazilian rhythm underneath real improvising, not bossa nova as background music.

It runs 8 to 10 PM at Arts Garage, 94 NE 2nd Ave in Pineapple Grove. Tickets are $50.50 to $55.50 and, unusually, the fees are already inside that number, so what you see is what you pay. Arts Garage is a nonprofit working out of a genuinely small room, which means the back row sits closer to the band than a good seat does at most venues. There is a full bar during shows. The box office is 561-450-6357, open Tuesday through Saturday 1 to 5 PM and during performances.

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