Do You Prune Osteospermum Before or After It Blooms?

Flowering Season

• African daisies have a long blooming season, starting in spring and lasting through the fall. Depending on warmth, plants may begin to bloom in late winter in subtropical parts of South Florida, Hawaii or coastal Southern California. In these climates, frosts don't occur so African daisies are offered for sale in winter to plant outdoors to bloom the rest of the year. Farther north, African daisies aren't available -- and shouldn't be planted outdoors -- until after the last spring frost date. Plants are seasonal annuals and are killed by the return of frost that autumn. Do not cut back the plants before they bloom if you grow African daisies as an annual bedding plant.

Deadheading

• Repeated trimming off of old flower heads and stems from the African daisy encourages reblooming. This is known as deadheading. Deadheading prevents plants from focusing energy into seed production. If the withering flowers are cut off, the plant again develops more flower buds in an effort to still produce seeds later on. Continually cutting off old flower stems keeps the African daisy continually producing flowers over the summer and into autumn before frosts.

Rejuvenation

• If you planted an African daisy in spring and it created a flush of flowers but now is tall, gangly and rather peaked, you may prune the plant back by 50 percent. It will rejuvenate with more branches and begin to bloom again with a fuller, bushier plant silhouette several weeks later in summer. If you garden in a frost-free subtropical area, rejuvenation pruning may occur in spring or very late summer. Do not conduct a harsh pruning within two months of an expected fall or winter frost. There's likely not ample time for the plant to rejuvenate fully and bloom again to its fullest potential. Blooming may start up, but the frost will kill the plant. It's better to rejuvenate earlier and then just deadhead flowers for the months leading up to frost.

Regrowth Insight

• Deadheading may be done anytime of year to encourage reblooming. However, harsher pruning often leads to disappointing results if the plant is not growing in ideal conditions. African daisies need at least eight hours of sunlight each day and an evenly moist, well-drained soil. Too much shade and wet soil -- from poor drainage or over-watering -- leads to leaf, stem and root rot. If your climate's summertime weather is rainy and humid, delay rejuvenation pruning until the seasonal regime changes and warm, slightly drier, lower humidity prevails. Conversely, hot, bone-dry soil prevents the African daisy from supporting healthy, widespread new growth.