Gerberas originated in the granite mountains of Barberton and thrive in these eroded sandy soils, which are well drained and hold little water. Well drained soil with a minimum depth of 30cm is necessary. The soil should be free of clay particles and can be 25% composted. The pH level should be 6,0 -7,0.
Gerberas are very vulnerable to soil diseases and too much water will result in root and crown rot. Never give too much water and ensure that all irrigation water is drained. The hybrid cultivars cannot tolerate water on their leaves and an underground irrigation system is required. Irrigation should commence in the early morning and cease by 2 pm to allow drainage from the roots.
Fertilisation and cultivating
The best method of providing the necessary nutrient requirements is through the irrigation system or by means of a slow-release fertiliser. Nitogen at 200-250 ppm is preferred and a low ammonium fertiliser such as 15-15-18 is recommended. Irrigation water should have a pH between 5,5 and 6. For best flowering results during spring and summer, a balanced micronutrient application is necessary. Gerberas require more boron and calcium for flowering.
The sowing of Gerbera seeds in a landscape area will not result in a lush bed of flowers. It is best to propagate them in large plug trays and transplant the young plants after six to eight weeks into the landscape area. Plants should be propagated in a sowing medium of 60% peat and 40% perlite.
North-facing rocky areas are ideal for Gerberas. Nine plants per square metre are recommended. Plant Gerberas with the crown 2 to 3 cm above ground level since the plant will pull itself into the ground in due course, and ensure that the crown section receives direct sun.
The main insect pests affecting Gerberas are spider mites, leaf miners, white fly and aphids. The main diseases are powdery mildew, bacterial blight, crown rot and root rot. |