Throughout his productive career, spanning over 40 years, Prof. van Staden's main research interests have encompassed topics relating to plant hormones and their role in the regulation of plant growth, germination, flowering and senescence. He is widely acknowledged for having expertise in plant tissue culture, and was a pioneer researcher on the topic of smoke-stimulated seed germination, a phenomenon that was only discovered in the early 1990s. He has also researched and published on topics related to proteas, algal biotechnology, plant biotechnology, molecular biology and South African medicinal plants.