Philodendron Care Guide
Native to the tropical and subtropical Americas, Philodendron is a massive aroid genus containing over 400 species (different sources provide different numbers, more on why later!). The name means 'lover of trees', due to the fact that most species cling to and climb massive trees in the rainforest to reach sunlight. Similar to Monstera, most Philodendron spend at least part of their lives as an epiphyte.
Because of their abundance and diversity, it is difficult to pin down a single care regimen for Philodendron. Many common houseplant species including Philodendron micans and cordatum are typically allowed to trail from hanging baskets or vine along a Bannister whereas others such as philodendron pedatum are usually staked or tied against a moss covered pole. Similar to Monstera, many Philodendron species will develop more mature, differently shaped leaves as they grow vertically and attach aerial roots to a tree (or moss pole). Others such as Philodendron xanadu are terrestrial and will do well when grown in a standard pot with well-draining media.
The huge variation in leaf structure not only between Philodendron species but also between the mature and immature leaves within a species has led to an abundance of confusion when attempting to classify this genus. Many species are still debated as to whether or not they are true Philodendron, and the plethora of botanical hybrids and varieties has only added to the confusion.
Recently, new phylogenetic analysis using DNA has resulted in a reclassification of many terrestrial species including Philodendron selloum (xanadu, hope). These woody almost tree-like plants are now technically classified as Thaumatophyllum, although most hobbyists and growers are slow to accept these reclassifications and so we continue to keep these species in our 'Philodendron' section.
Like all epiphytic and partially epiphytic species, they do not like to have waterlogged roots and will appreciate a very well draining soil that contains a high percentage of sphagnum or peat moss, coconut fibre, or similar material. For many species, it is best to let the substrate dry most of the way between waterings to reduce the risk of root rot. You can easily just stick a finger into the soil to test the moisture level, or purchase a cheap moisture meter (usually under 15$) to stick in the soil and water when it says slightly dry. Philodendron are relatively tolerant of drought, however as many are epiphytic they are prone to root rot.
Similar to other plants from the rainforest understory, most Philodendron will not tolerate direct sunlight on their leaves and will quickly develop burns or brown crispy patches on their leaves if left in direct sunlight. Bright indirect light is perfect, however many species will tolerate lower light conditions making them excellent houseplants.
Philodendron are susceptible to all the most common houseplant pests: particularly spider mites and thrips. Spider mite damage will appear as yellow speckled, sad looking leaves with a fine spider-like webbing on the underside of leaves, around petioles, and on the stems.
Thrips will likely first make their presence known by the growth of new misshapen or deformed leaves. In addition to this damage to young leaves and shoots, old leaves may develop yellow or brown patches and the underside of leaves might reveal brown speckling, which is the thrips feces.