Common Butterwort
Quick Facts & Botanical Stats
Species Overview
What is a butterwort? The common butterwort (Pinguicula vulgaris) is a small carnivorous plant in the Lentibulariaceae family. Found across cold northern latitudes and alpine slopes, it is famous for its rosette of greasy, yellowish-green leaves. It uses flypaper-like traps to catch insects, secreting sticky mucilage from glandular hairs on its leaves.
Physical Appearance & Anatomy
What does a butterwort look like? The plant grows as a small, flat rosette. The leaves are succulent, oblong, yellowish-green, and have edges that curl slightly upward. Why are the leaves greasy? The leaf surface is covered in microscopic glands that secrete a sticky fluid, making the leaves look greasy or buttery. In spring, it produces a single, nodding purple flower resembling a violet.
Habitat & Growth Behavior
Where do butterworts grow? They grow in damp, nutrient-deficient soils, alpine bogs, wet limestone seeps, and rocky mountain ledges. How do they survive winters? To survive freezing arctic and alpine winters, the plant dies back to a tight, dormant winter bud called a hibernaculum, which rests on the soil. In spring, it emerges and grows rapidly using nutrients stored in the bud.
Ecological Role & Symbioses
What do butterworts eat? They feed on small flying insects, including gnats, fruit flies, and midges. How does digestion work? When an insect gets stuck, the leaf margins slowly curl inward to seal the prey, and specialized glands secrete digestive enzymes. In Northern Europe, the leaves have historically been used to curdle milk to make a traditional Swedish yogurt-like food (tätmjölk).
Reproduction, Lifecycle & Propagation
Butterworts reproduce sexually. The single purple flowers are pollinated by bees and flies, developing into capsules containing tiny seeds. The seeds are dispersed by wind and water. Vegetatively, they propagate by producing small offset bulbils around the hibernaculum in winter. They grow slowly, taking 2 to 3 years to bloom, and live for 5 to 10 years.
Conservation Status & Environmental Threats
Pinguicula vulgaris is classified as Least Concern on the IUCN Red List. It is widespread in subarctic zones. However, localized alpine populations face threats from tourism, drainage of alpine seeps, and nitrogen deposition from air pollution, which reduces their competitiveness. They are protected in national parks.
Interesting Fun Facts
- The common name 'butterwort' comes from the greasy, buttery feel of its leaves, which are covered in sticky glandular hairs.
- In traditional Scandinavian folklore, butterwort leaves were used to curdle milk, making a thick, sour yogurt called 'tätmjölk'.
- To survive freezing arctic winters, the plant shrinks into a tiny, cabbage-like winter bud called a hibernaculum.
- The leaves are covered in two types of glands: one to trap the insect like flypaper, and another to digest it.
Related Plants
Cape Sundew
Least ConcernWhat is a cape sundew? The cape sundew (Drosera capensis) is a small carnivorous plant belonging to the Droseraceae family. Native to South Africa, it is one of the most famous sundew species. How do sundews trap insects? It uses flypaper-like traps, consisting of leaves lined with tentacles that secrete sticky, glistening droplets of mucilage. Insects are attracted to the drops, get stuck, and the leaf slowly rolls up around them to digest them and extract nutrients.
Venus Flytrap
EndangeredWhat is a Venus flytrap? The Venus flytrap (Dionaea muscipula) is a small carnivorous plant belonging to the Droseraceae family. Native exclusively to the nitrogen-poor coastal bogs of North and South Carolina, it is globally famous for its rapid, active leaf traps. Why is the Venus flytrap carnivorous? Because it grows in nutrient-starved, acidic soil, it has evolved traps to catch insects, digesting them to absorb essential nitrogen and phosphorus. Charles Darwin famously described the Venus flytrap as 'one of the most wonderful plants in the world'.