Pinguicula macroceras, commonly known as the California butterwort or horned butterwort, is a perennial carnivorous herb native to moist, nutrient-poor habitats such as bogs, fens, and wet meadows along the North American Pacific coast. It is also found in similar environments in Canada, Russia, and Japan. This species typically grows less than 8 inches tall, with fleshy, sticky leaves that form a basal rosette, enabling the plant to trap and digest small insects to supplement its nutrient intake. The California butterwort produces 1-5 showy purple-blue flowers on slender stalks that rise above the foliage, blooming from late spring to early summer.

The plant is valued for its unique carnivorous nature and the striking purple-blue flowers that add a splash of color to bog gardens and other water features. It is often used in cultivation to control small insect populations naturally. Pinguicula macroceras prefers full to partial sun exposure and requires consistently moist, acidic soils with good drainage to mimic its native boggy conditions. While it is relatively low maintenance, it can be sensitive to water quality and may require distilled or rainwater to avoid mineral build-up. It is not known for significant disease issues, but overwatering or poor drainage can lead to root rot.CC BY-SA 4.0