Tropical Butterworts (Pinguicula) Cultivation
General Info:
Butterworts (genus: Pinguicula) are a type of carnivorous plant that uses slimy, sticky leaves to catch small gnats and flies. While some species grow in bogs, the “Mexican” or “Tropical” butterworts typically grow on rocks, cliffs, and seepages in the mountains of Central America. This group of species is the most diverse of Pinguicula groups, distinct for their preference for very light, airy substrates, and their dry, winter dormancies. In their native habitats, winters are cool and dry, inducing growth of tightly packed, non-carnivorous succulent leaves. When moisture returns in the spring, they will grow new sticky, carnivorous leaves throughout the year.
The Tropical Pinguicula include over 50 different species with highly variable leaf shape and flowers. Flowers are typically shades of lavender, purple, magenta, or white. While not necessarily difficult to grow, getting the proper conditions dialed in can take some trial and error. Unlike most other carnivorous plants, these Pinguicula prefer very granular, well draining media. Their root systems are simple and shallow, though prone to rot if conditions are too wet. Growers will use a huge range of different soils and watering methods since no one method works for everyone in all conditions. They appreciate foliar feeding with MaxSea.
Cultivation:
Moderate to high Light - give them a few hours of sunlight per day or at least 15W per square foot of LED grow lights. The more light, the more colorful the leaves.
Watering with the tray method will depend on the soil. Plants can also be top watered, but again the soil will dictate the frequency. I’d recommend using a shallow tray (~0.5”) and a very granular soil that becomes moist but not soggy at the surface.
Temperatures between 50-85F are best. They are adaptable to different humidity from low to high, though many species appreciate at least moderate humidity. Most species prefer cooler temperatures.
There are countless soil mixes that work, but Using widely available media, I would recommend 20% Peat Moss: 60% perlite: 20% sand. I also like equal parts Perlite: Volcanic Granules. They want an airy mix that does not compact. Some species prefer wetter or drier mixes.
Notes:
The most common cause of death is what is referred to as “browning heart disease” where the center of the plant turns brown and quickly dies. This is generally a fungal infection induced by overly wet, stagnant conditions.
Feed them by lightly spraying the leaves with dilute MaxSea every few weeks. Use 1/4 tsp per gallon of distilled or reverse osmosis water.
Some species will automatically go dormant when the photoperiod decreases in winter. Some will only go dormant when intentionally dried out slowly to induce the succulent phase. This is the easiest time to repot them since they are not actively growing.
Leaf pullings are very effective as a means of propagation. These can be taken from both carnivorous and succulent leaves. Simply pull off a leaf all the way down to the base and place on top of a moist soil in a humid environment. It will sprout a new plant in a few weeks.
More Information:
https://www.carnivorousplants.org/grow/guides/MexicanPinguicula