St. Lucia Botanical Gardens, Botanical garden with mineral baths in Soufriere, Saint Lucia.

St. Lucia Botanical Gardens, also called Diamond Botanical Gardens, covers about 2 hectares on the Diamond Estate in Soufrière. Joan Devaux laid out the garden in the 1980s around the Diamond Falls, a roughly 17-metre cascade coloured by sulphur springs. Palms, bananas, citrus and cocoa grow among hibiscus, ginger, heliconia and vanilla.

A French nobleman constructed the thermal baths in the late 18th century with royal support to make use of the natural hot springs for treatment. The site grew from efforts to develop the geothermal resources found beneath the land.

The gardens serve as a place where visitors connect with the island's natural thermal springs and tropical vegetation in a single space. This combination reflects how locals have long valued the healing properties of the mineral waters alongside the beauty of the surrounding plants.

A path from the baths continues past the Diamond Falls to an old sugar mill that still holds a water wheel dated 1765. The cascade drops about 17 m, and swimming is not permitted there; the mineral baths are the bathing area. The garden covers roughly 2 ha on the Diamond Estate.

The waterfall displays shifting colors throughout the day due to high mineral content in the water. These color changes occur as sunlight hits the mineral deposits on the rock surface at different angles.