Light:

Full sun (southern exposure).

Temperature:

As a potted plant, maintain indoor temperatures above 60°.

Humidity:

Preferably 50% or higher; however they will tolerate low levels for short periods with no harm.

Watering:

Bring soil to a state of visual dryness between waterings.   When watering, thoroughly saturate soil until a little water runs out of the bottom of the pot.

Fertilizer:

They are moderate to heavy feeders so a 1/2 tsp./gallon once a week is a general recommendation, or ¼ tsp at every watering throughout the growing season.   When growth slows in winter, discontinue feeding.   Use a balanced fertilizer, i.e. 15-15-15 or a blooming fertilizer like Pro Gro ‘Grow’ 7-9-5 or Electra 5-10-3.

Pruning:

Generally they are pruned at any time of year whenever growth is excessive.   However, as they bloom on the long day length and high light intensity of summer, pruning from early spring through fall will disrupt flowering.

Insects and Disease:

They have susceptibility to whitefly, spider mite and aphids.  Root diseases can be a problem under cool damp conditions.  Growing them warm, under high light and bringing the soil to visual dryness between waterings will help mitigate the problem.

Comments:  

Pentas are fast-growing plants that bring months of flowers to the garden and potted container.  They do require lots of direct sunlight for best growth and flowering.