Phenological studies have been used for centuries, particularly in agriculture, and are useful to determine species-level responses to climate among other long-term variations. A previous study of phenology at the Tierberg Karoo Research Centre (now Tierberg Long-Term Ecological Research), focussed on how life form and landscape location influenced growth and flowering. In 2017 SAEON started a new phenological study to investigate the long-term phenology of five plant species (Ruschia spinosa, Osteospermum sinuatum, Pteronia pallens, Drosanthemum praecultum, and Galenia fruticosa). Ten plots with five replicates of each species (250 individuals in total) were observed at least once a month.

Key findings:

Over the course of 6 years, including a significant dry period, 35% of individuals had died. The most notable species results were that R. spinosa had no fatalities and that G. fruticosa suffered 86% mortality.

All species showed considerable growth and flowering after good rains irrespective of season

All of the observed species flowered in spring with fruits forming near the end of spring and being ripe in summer