The importance of crown data in improving the reliability of growth models for stand management has long been established, but such data are scarce for tropical forests. This paper reports studies of crown diameter–bole diameter relationships of five mixed tropical forest species by regression methods. The regression explained 77% of the variation in crown diameter. Growing space was associated with crown size, and models were developed from which growing space, limiting stocking and stand basal area density can be predicted. The paper demonstrates, e.g., that trees of 60cm bole diameter would each require 0.009ha of growing space with a density of about 107stemsha⁻¹. Stand basal area converges around 31m²ha⁻¹. In silvicultural practice, the baseline information provided by this study could serve as a guide for planting distances and crop density in industrial plantations of similar indigenous mixed tropical forest species.