This Florida Keys Eco-Resort Is a Masterclass in Barefoot Luxury

A boutique resort built around serenity and sustainability

Photo: Grassy Flats Resort and Beach Club

When I was first greeted by fanned palm fronds, I knew I had stumbled upon a jewel in Marathon. The landscaping at Grassy Flats is dense and breathtaking, creating the illusion, at times, that you’ve retreated into a Bahamian thicket.

I settled into the Humidor House during my visit, which has rooms opening onto private balconies overlooking a serene island retreat. Be prepared to fall in love with your view of the sandy beachfront, swaying palms, and sparkling tide. The room’s leather and dark-wood furnishings harken back to Florida’s rum-running roots, evoking Prohibition-era cigar lounges and shadowy speakeasies. It’s a vibe that’s somewhat unexpected for a coastal paradise, but it feels elegant and relaxing.

The Humidor House is one of two adults-only room types on the property, with an adults-only pool and hot tub to boot — a rare find when visiting the Keys. I enjoyed my time poolside, splash- and cannonball-free.

The 50-acre property has seven room types, each with a different theme and a variety of accommodations for every type of vacationer, including double rooms, king suites, and multi-room condos with full kitchens.

Photo: Grassy Flats Resort and Beach Club

Grassy Flats takes pride in offering a luxurious escape while prioritizing sustainable principles. Resort operator, eco-enthusiast, and jack-of-all-trades Matt Sexton has styled his chic spaces with reclaimed wood and materials from his own salvage and waterway cleanup efforts. His full-scale recycling initiative prevents thousands of pounds of waste from ending up in Florida landfills each year.

In fact, Grassy Flats protects the Middle Keys ecosystem through a number of earth-positive practices. Sargassum, the naturally occurring seaweed that washes up on the shoreline, is managed to help preserve the local turtle population and fertilize the grounds. It’s part of a dune restoration effort to combat erosion.

“For the first time in 10 years, we’ve had turtles nest on this beach,” said Sexton. “So, by planting this native dune right here, we’ve built these bridges the turtles are climbing. They have a really nice easy access and can come up onto the beach.”

There are organic fruit orchards and a butterfly garden on-site, creating welcoming spaces for native bird species and pollinator insects. An inconspicuous feature of the property is the 50,000-gallon rainwater cistern, which helps irrigate the landscape.

With daily access to pools, a sauna, a cold plunge, restaurants, bars, bicycles, kayaks, and paddleboards, travelers can turn up or turn down at their own speed. The beauty of such a wide variety of environmentally friendly activities is the reduced carbon footprint they create, which directly supports the resort’s conservation efforts.

Water sports, catamaran cruises, and a sister property to explore

Photo: Grassy Flats Resort and Beach Club

After a long day of travel, my room’s spacious, plush king bed was a comfortable place to land and a peaceful nest to welcome the rising sun. The hushed atmosphere felt worlds away from my mornings at home in Maryland, where the delivery trucks routinely rattle through the neighborhood, slamming into the speed bumps before dawn.

I excitedly prepared for a kayaking ecotour, one of many firsts I would enjoy at Grassy Flats. Grassy Flats is the home to the Florida Keys Watermans Company, Sexton’s brainchild that pairs his passion for water sports with his knack for hospitality and coaching. The on-site adventure team makes this Middle Keys resort a top choice for canoeing, e-foiling, kayaking, kitesurfing, windsurfing, paddle boarding, and more.

After donning a life vest and listening to tips and safety reminders from Sexton, I was ready to pick up my paddle and slide into a kayak. Once I was pushed beyond the limestone barrier, I found the current was still. The breezes were gentle and the water so clear I could see down to the ocean floor, marveling at the schools of tiny shimmering fish cruising between the seagrass. While our group paddled along, Sexton shared his vast knowledge of Florida backcountry lore and ecology, mentioning the Florida Keys’ historic railroad and the Florida Forever wildlife preserve.

Photo: Jasmine Taylor

Once getting settled back on dry ground, I headed to Grassy Flat’s sister property, The Lagoon at Grassy Key. Adorned with vibrant murals and bountiful fruit trees, this spot is a must-see for anyone with an eye for beauty. Visitors can opt for low-impact transit by borrowing a bike and taking a five-minute ride down the road.

Sexton literally built the site from the ground up, transforming a former abandoned fish farm and limestone quarry into a wakeboarding park. Sexton’s solo years in the Lagoon trailer home would eventually help shape his vision for what would become a waterpark, beer garden, cantina, surf shop, art installation, and botanical garden.

“It was probably the best couple of years of original thoughts I’ve ever had in my life,” Sexton reflected. “That’s one of those things I try to let people unlock here and unwind.”

He describes the Lagoon as a patchwork quilt, showcasing 15 years of salvage-haul recycling, hurricane cleanup efforts, and site restoration. His previous home still stands, now repurposed into a restroom for patrons; the old fish farm is home to the Lagoon Saloon Surf Shop; and Bongos Cantina is outfitted from a shipping container and reclaimed wood. Each piece brings a rustic, beachy charm to the site, even though the ocean isn’t within view.

Lunch at Bongos Botanical Beer Garden was exactly what my rumbling tummy needed after an action-packed morning. I had the huli huli chicken, a sweet and saucy grilled chicken dish served with rice, bold mango salsa, fresh avocado, and tangy pickled red onions. Be sure to stop by the bar and order the Grassy Gatorade, a thirst-quenching punch of rum, watermelon juice, coconut water, and fresh mint.

Afterward, I spent my time taking in the artwork and frolicking through the botanical garden. Sexton pointed out all the trees, including mango, cherries, jackfruit, coconut, banana, and tamarind. I tasted sapote, a soft, syrupy fruit with nectar-like brown sugar. The eye-catching murals tell Grassy Flats story through bold brushstrokes, from the depiction of the resort’s resident orange cat, “Wilma”, to Sexton’s children.

Photo: Jasmine Taylor

The next day, I would find myself back on the Florida waters, this time on a small catamaran. Sexton and the team at the Florida Keys Watermans Company station prepared the Hobie Cats for our voyage, adjusting sails, knotting ropes, and captaining the vessels. We took off in a flash, smooth at first, then skipping across the surf. Between the cooling spritz of the ocean spray, the whipping winds, and the cerulean sky, I didn’t think the day could get any better. Our arrival at a sandbar would prove me wrong. Here, the warm, calm waters were crystal clear. Below, a stingray glided through the shallows while cormorants soared overhead.

The lightweight watercraft is entirely powered by the wind and the current, making it a zero-emissions and zero-waste way to enjoy the ocean. The sailing trip marked another personal first for me, completely stretching my perception of leisure water sports and who gets to enjoy them. I returned to shore exhilarated and ravenous, ready to sink my teeth into something delicious.

Dockside dining, classic Florida flavors, and saying goodbye to the Keys

Grassy Flats has four unique on-site restaurants, each committed to serving food at peak freshness. It’s easily a community forerunner in the dockside-to-table scene due to its commitment to ethical, sustainable sourcing practices. The fish is locally caught, and beef and chicken are farm-raised and butchered on site.

Sexton remarks that the menus were created with every palate in mind; guests craving a fresh fish sandwich for lunch and filet mignon paired with a Robert Foley red by dinnertime will be able to enjoy the best of both worlds.

“At first [the menu] was too fancy, and that wasn’t our identity. We’ll sell a little caviar and a little bit of oysters, [but] everybody wants a cheeseburger in paradise,” he remarked.

For breakfast or lunch, you can fuel the day’s adventures at Grassy Key Land & Sea Market. At the luncheonette, I ate a piping-hot sausage, egg, and cheese sandwich on a buttery, flaky homemade biscuit. If you need your coffee first thing in the morning, you can get a steamy cup of the good stuff as early as 6 AM. Aside from the hearty meal options, shoppers can also peruse the finest selection of butchered meats, freshly caught fish, beer, wines, and other kitchen staples. It’s an atmosphere reminiscent of Sexton’s upbringing in New York City while working in a small, family-owned deli.

You won’t want to miss The Palm Deck, a chic rooftop bar offering small plates and perfectly crafted cocktails served with a side of sunshine and clear blue sky. Order the felon fish dip for the table, a yummy blend of smoked wahoo, zesty red onion, and pickled chilis served with thin, crunchy plantain chips. Those who have never had conch should try it here in the form of the Caribbean conch croquettas, a flavor bomb of minced conch enveloped in a crispy fried exterior, topped with a bright lemon-garlic aioli. I nursed a refreshing Grassy flamingo cocktail, saluted the setting sun, and enjoyed the live, foot-tapping tunes before my last meal of the day.

Photo: Grassy Flats Resort and Beach Club

Undoubtedly the darling of Grassy Flats, the Rhum House showcases an intimate, inviting dining space perfect for a moonlit dinner. The sommelier-curated wine selection, exceptional entrées, decadent desserts, and immaculate service could position this restaurant as a culinary tastemaker in the Keys. Its approach to my favorite local staples has forever sullied my taste buds; the sweet, succulent stone crab claws are the most delicate and tender I’ve ever had, likely due to the catch’s freshness. For your main course, you can’t go wrong with a certified Angus filet accompanied by steamy, juicy, and garlicky Key West pink shrimp. Satisfy your sweet tooth with a slice of Key lime pie so heavenly that the meringue topping had to have been whipped by angels and sealed with a kiss.

My last hurrah, a sunset cruise hosted by Grassy Flats, would be my reluctant farewell to the Keys. Sexton was our skipper for the evening, touring us around the Florida Bay. The highlight of the evening was cruising under the Seven Mile Bridge and stopping past the Sombrero Key Lighthouse. While watching the sun’s gilded cascade dance across the ocean’s surface, I reflected on my time at the resort. Grassy Flats is truly a place where you can check in, unplug, and stay on the property until it’s time to go home. Despite my many pilgrimages to the Keys, my most memorable firsts happened at Grassy Flats — a place that dared me to try something new.

Getting to Grassy Flats

Grassy Flats Resort & Beach Club is a 75-minute drive from Key West International Airport (EYW) and roughly 2.5 hours from Miami International Airport (MIA) or Fort Lauderdale-Hollywood International Airport (FLL) (depending on traffic). Airport rental cars are in high demand, so book in advance before you get on your flight.