Some philodendron flowers heat up, burning oxygen as fast as hummingbirds do
During flowering, some philodendrons warm the central spike of their bloom in three separate peaks. The heat stirs up beetles sheltering inside, spreads scent into the air and may even prompt the insects to mate. Fuelling it, the flower consumes oxygen at a rate close to that of hummingbirds and sphinx moths.
The heating happens in a sterile zone of the spadix, the flower spike. A build-up of a particular acid there switches the cells' mitochondria onto an alternative energy route, the cyanide-resistant pathway, which releases energy as heat. Stored carbohydrates burn first; once the spike reaches its top temperature, fats are oxidised directly. The spadix gives off measurable infrared radiation, and holding it at an angle of 45 degrees to the surrounding hood may help waft scent outward. Drops of sticky resin on the spike glue pollen to visiting beetles, a trick shared only with Monstera among its relatives.
Philodendron is a big genus, with 625 species accepted as of September 2025, second in its family only to Anthurium, and many species still undescribed. Its name joins the Greek for love and tree, apt for plants that so often climb. Many are familiar houseplants.
Their growth strategies vary more than most of their relatives'. Some sprout high in the canopy, live as epiphytes, then send aerial roots down to the soil, trading nutrients early in life for light. A few of these host ant nests among their roots, feeding the ants with nectar glands and gaining nutrients and bodyguards in return. Others germinate on the ground and climb upward, sometimes eventually letting go of the soil entirely.
Ground starters that sprout away from a tree have a clever search method. They creep along with long stem segments, growing toward darkness, because the deepest shadow usually marks a tree trunk. This is called scototropism. Once they reach a tree, they switch to growing toward light, and their stem segments become short and thick. A few species, such as Philodendron fragrantissimum, alternate between tight clumps of leaves and bare stretches of stem a metre or more long.
Source: Philodendron
