Temperature is the main environmental factor determining the release period of encapsulated controlled-release fertilisers (CRFs). Therefore, an understanding of container media temperatures is important to the nursery grower. The aim of this work is to review the factors influencing container media temperature, its effect on plant growth, and to try to establish to what degree various parameters influence the relationship between air and container media temperature. Such an understanding will hopefully allow a more accurate prediction to be made as to container media temperatures based on air temperatures. The latter are more readily recorded and would consequently assist in the estimation of the longevity of CRFs.