how to care for heliotrope heliotrope is tropical plant aptly named as its leaves and flowers turn toward the Sun following it throughout the course of the day readjusting towards the east in the evening to be ready for the sunrise delicious deep purple brilliant blue or white colored clusters of flowers appear in the spring lasting until fall their delicious fragrance has been compared to apple pie in vanilla growing to heights of 12 to 36 inches this plant works well in window boxes containers and garden borders things you will need fertilizer place your heliotropes where they will get full Sun throughout the day filtered sunlight it okay in the afternoon but this plant thrives in full Sun water daily to keep the soil moist do not let the soil dry out use well-drained soil and make sure the plant is not sitting in water fertilize once a month use a water-soluble slow release fertilizer 10-10-10 works well cover heliotropes with 2 to 3 inches of mulch if they're outside this protects the plant from cold weather and holds in moisture trim the young plant regularly by nipping off the tips of the plant to encourage a bushy appearance deadhead regularly to increase the flower production check over your plant for mildew which can be a problem if plants are overcrowded if necessary space your plants out further wipe leaves with a cloth if mildew is present and cut off affected leaves generally Hylian troops are pest free