Orange star plants are hardy in U.S. Department of Agriculture planting zones 7 through 11. Orange stars can be grown indoors if temperatures are too cold for successful winterizing. Watering and pruning are important to maintain healthy plants.Continue Reading
Orange stars prefer soil that is moist and drains well. Plant the orange star in a raised bed, rock garden or sandy soil 3 inches deep and 3 to 6 inches apart.
Closed buds and leaves are prey to thrip. Many thrips hide on the underside of leaves and cause discoloration or leave tiny black dots. Prune affected stems and leaves, and spray with a strong stream of water to remove any remaining thrips. Orange star flowers are vulnerable to fungal diseases. If rusty brown spots appear on the plant, spray with a fungicide approved for ornamental plants.
As flowers die back, remove them to improve the appearance of the plant and to make room for new buds. When the foliage turns yellow, prune it to the ground in preparation for the next growing season.
If the soil doesn't drain well, remove the bulbs in winter to prevent root rot. Store roots in a mesh bag in a dry, well-ventilated location.
The U.S. Department of Agriculture, Agricultural Research Service's hardiness zones are temperature zones that aid growers in deciding which kinds of plants survive the winter in certain locations. The department determines the zones based off of minimum average annual winter temperatures across the United States. It divides these into 13 zones between -60 and 70 degrees Fahrenheit, each representing an interval of 10 degrees. As of September 2015, the USDA calculated hardiness zones using data from 1976 to 2005.Full Answer >
In U.S. Department of Agriculture hardiness zones 7 and 8, dig up gladiolus bulbs after the foliage has died and before the ground freezes. Gladiolus bulbs are food-storage structures called corms.Full Answer >
The true citronella plant grows best in U.S. Department of Agriculture hardiness zones 10 through 12. Cymbopogon nardus is a grass native to Southeast Asia from which citronella oil is derived. It prefers to grow in slight shade in a well-draining, loamy soil.Full Answer >
Some perennial autumn-blooming flowers in U.S. Department of Agriculture zones four through nine are rudbeckias, asters and chrysanthemums. Calendulas and bachelor’s buttons are annuals that bloom in the fall.Full Answer >