Best Plants to Improve Indoor Air Quality

Heartleaf philodendron

Philodendron hederaceum — heartleaf philodendron

Philodendron hederaceum, also known by the common name heartleaf philodendron, is a species of flowering plant in the family Araceae, native to Central America and the Caribbean.

It is an evergreen climber growing to 3–6 m (10–20 ft), with heart-shaped glossy leaves to 30 cm (12 in) long, and occasionally spathes of white flowers in mature plants.

With a minimum temperature requirement of 15 °C (59 °F), in temperate regions it must be grown under glass or as a houseplant.

Philodendrons can be grown outdoors in mild climates in shady spots. They thrive in moist soils with high organic matter. In milder climates, they can be grown in pots of soil or in the case of Philodendron oxycardium in containers of water. Indoor plants thrive at temperatures between 15 and 18 °C and can survive at lower light levels than other house plants.

Although philodendrons can survive in dark places, they much prefer bright lights. Wiping the leaves off with water will remove any dust and insects. Plants in pots with good root systems will benefit from a weak fertilizer solution every other week.

Yet another use of philodendrons is for catching fish. A tribe in the Colombian Amazon is known to use Philodendron craspedodromum to add poison to the water, temporarily stunning the fish, which rise up to the surface, where they can be easily scooped up. To add the poison to the water, the leaves are cut into pieces and tied together to form bundles, which are allowed to ferment for a few days. The bundles are crushed and added to the water into which the poison will dissipate.

Although the toxicity of Philodendron craspedodromum is not fully known, active ingredients in the poisoning of the fish possibly are coumarins formed during the fermentation process.

Some philodendrons are also used for ceremonial purposes. Among the Kubeo tribe, native to Colombia, Philodendron insigne is used by witch doctors to treat ill patients. They use the juice of the spathe to stain their hands red, since many such tribes view the color red as a sign of power.

Philodendrons can contain as much as 0.7% of oxalates in the form of calcium oxalate crystals as raphides. The risk of death, if even possible, is extremely low if ingested by an average adult, although its consumption is generally considered unhealthy.

In general, the calcium oxalate crystals have a very mild effect on humans, and large quantities have to be consumed for symptoms to even appear. Possible symptoms include increased salivation, a sensation of burning of the mouth, swelling of the tongue, stomatitis, dysphagia, an inability to speak, and edema.

Cases of mild dermatitis due to contact with the leaves have also been reported, with symptoms including vesiculation and erythema. The chemical derivatives of alkenyl resorcinol are believed to be responsible for the dermatitis in some people.

Contact with philodendron oils or fluids with the eyes have also been known to result in conjunctivitis. Fatal poisonings are extremely rare; one case of an infant eating small quantities of a philodendron resulting in hospitalization and death has been reported.

As to the toxicity of philodendrons in cats, the evidence is conflicting. In one study, 72 cases of cat poisonings were examined, of which 37 resulted in the death of the cat. The symptoms of the poisoned cats included excitability, spasms, seizures, kidney failure, and encephalitis. However, in another study, three cats were tube fed Philodendron cordatum and showed no signs of acute poisoning. In this study, two adult cats and one kitten were fed a puréed leaf and water mixture, observed afterward, then euthanized, and finally a necropsy was performed.

Some philodendrons are, however, known to be toxic to mice and rats. In one study, 100 mg of Philodendron cordatum leaves suspended in distilled water were fed to six mice. Three of the mice died.