In this paper, using a spatial broadband channel model taking into account transmit and receive antenna correlation, we study the influence of propagation conditions on the performance of space-frequency coded OFDM. For a given space-frequency code, we quantify the achievable diversity order and coding gain as a function of the transmit and receive correlation matrices. We find that the presence of transmit correlation results in widely varying performance losses. High-rate space-frequency codes such as spatial multiplexing are typically significantly more affected by transmit correlation than low-rate codes such as space-frequency block codes.