‘Astra Sunset Purple’ and ‘Astra Pink Silver’ are two new introductions to the Astra series this year. Other colors offered are Violet, White, Pink Yellow, Peach Ice, Yellow, Pink Spoon and Purple Spoon. Astras were bred to branch and have a compact habit. They are well suited to be grown in 4- to 10-inch hanging baskets. They will grow to fit the pot size.
Astra varieties have a very low cold requirement, so they can be grown without a traditional cold period. They may be grown at 60-65° F. Pinching at the third node cab is beneficial but not necessary. Grow at a pH of 5.6-6.0 and EC of 1.2, using a 2 to 1 soil test. In propagation, osteospermums need a soil temperature of 72-75° F. Rooting hormone is beneficial to promote rooting. A wetting agent spray after sticking may help avoid excess wilting.
Plant growth regulators are not usually needed on Astra varieties, but some of the newer varieties may need some B-Nine (daminozide), Cycocel (chlormequat chloride) or A-Rest (ancymidol).
Osteospermum have very few pest problems, but a good preventive insecticide program is always recommended. Fungi such as Botrytis,
Phytophthora and Pythium should be covered in a preventive spray