Geraniums prefer bright light. Bedding or potted geraniums need full sunlight for best flowering.
Moderately dry soil is preferred. Water thoroughly when the soil is dry to the touch. Disease can be a problem if plants are over watered. If it is a potted geranium drain the excess water in the saucer at base of the pot to prevent root rot and protect the furniture.
Cool/Moderate temperatures are ideal: 60-70 F (15-21 C) daytimes and 55-65 F (13-18 C) nights. Martha Washington geraniums prefer temperatures no higher than 65 F (18 C) daytimes and 60 F (15 C) nights.
Key tip for success: Martha Washington geraniums prefer the cooler days of early summer for flowering but have attractive foliage even when not in flower.