There are over 500 plant species recorded. Seven of these are Red Data Species. They are Lampranthus reptans, Euphorbia marlothiana, Psoralea glaucina, Psoralea repens, Satyrium carneum, Muraltia mitior, and Passerina paludosa. There are also 25 Declared Invasive Plant Species in the reserve.
The Zandvlei Herbarium is kept at the Environmental Education Centre and houses a specimen of each of these plants. Because of mainly human pressures on the reserve, the existence of a number of plants is threatened.