Philodendrons can be accustomed to nearly direct sunlight in the right conditions, but they thrive in light shade. If you notice many of the leaves turning yellow at the same time, it can indicate you are giving the plant too much direct light. Keep the growing medium moist at all times. Some of the philodendron varieties are extremely fast-growers. Pinch off the new growth to keep the plant manageable and repot them annually as they outgrow their pots.