Philodendrons

Philodendrons are mostly climbing plants, and are among the most common and easy-to grow houseplants. Many tolerate low light and neglect, but if well treated, they will be beautiful and dependable for many years.  If you live far enough north, you can grow you philodendron outside, otherwise choose a greenhouse or indoors in a pot.

CULTIVATION

Indoors/Outdoors:

In mild, frost-free climates, Philodendrons can be grown outside in shady spots. They'll flourish in rich, moist soil that contains a good supply of organic matter. If grown outside, night temperatures down to around 15°C and day temperatures around 30°C are ideal.

If grown indoors, the lower temperature can often be reduced further, as the plant is protected from extreme cold and frost.

Habit: 

Philodendrons are climbing plants, but some will grow as ground covers – although they often have quite large leaves, so will still reach 50cm or more in height. 

If grown indoors, the climbing varieties will usually make beautiful indoor plants growing up a totem pole, or a hanging basket specimen.

If you prefer to keep it in a pot (whether indoors or out), give climbers some kind of support to cling to.  A totem pole, pieces of rough bark or stakes wrapped with a thick layer of sphagnum moss will serve well. You may need to prune it occasionally if it gets too big.

Light: 

Most philodendrons prefer indirect or filtered sunlight but will tolerate low light. They need to be shaded from direct sun.  Some light morning sun is usually ok.

Water:

High humidity is ideal for best growth, but philodendrons tolerate the low level of humidity in most homes. 

Water frequently enough to keep the soil evenly moist, but not soggy. Never let the plants stand in water.

Newly potted plants need to be carefully watered. Allow the soil to become almost dry before watering. Follow this procedure until the roots have grown into the new soil, after which the soil can be kept more evenly moist. It's especially beneficial to newly planted Philodendrons to spray their leaves two or three times a day.

Fertilize philodendrons regularly with a dilute water soluble houseplant fertilizer, or use a time-release fertilizer.

Pots:

Philodendrons grown in pots need well-drained pots that aren't too large for the plants. They do best when their roots are slightly cramped, but not too tightly packed that they form a tight ball of roots.

Most kinds of Philodendrons need supports to cling to.  A totem pole, pieces of rough bark or stakes wrapped with a thick layer of sphagnum moss will serve well.  Otherwise, many Philodendrons make very beautiful hanging basket specimens.

You can repot overcrowded plants at any season, using a general-purpose potting soil. Plants may be propagated at any season from stem cuttings, or by air layering.   Some philodendrons will produce offsets.

Problems:

In the home, plant diseases are very rarely a problem.  Too much or too little water plus insects and mites are the main problems.

Root rot usually results from a soil mix that does not drain quickly or overly frequent watering.

Yellowing of lower leaves and the death of the growing tips can be caused by too little light or overwatering. 

Too much fertilizer can cause tips of leaves to curl and brown.

While philodendrons are generally pest-free, aphids, mealybugs, scales and spider mites can infest them.

Some philodendrons contain a chemical that causes a burning sensation and can be toxic if the foliage is eaten.  Keep philodendrons away from any pets or young children that may eat plants.