Smallholder farmer agricultural productivity in developing countries is more often diverse and limited by diverse constraints. For optimal agricultural production and income crops for diversification must be carefully selected and the constraints properly addressed. The objective of this study was to establish a list of the major crops planted in the Bamboutos mountain landscape and the constraints faced by the smallholder farmers. During a survey, 261 household heads responded were randomly selected and the questions administered to them. A majority of the household heads were men and were literate and most of them were younger than 55 years. Crop and livestock production were the main income generating activities of the respondents. Most of the farmers` land sizes were less than 5a and land ownership was through inheritance, purchase or rent. The small holder farmers in the study area planted a variety of both annual and perennial crops. These crops were sold, consumed or had ornamental/cultural values. The farmers faced a number of problems in animal and crop production with the most cited constraints being lack of inputs, lack of capital, bad roads and climate change. The results of this study suggest that crop diversification should be encouraged within the study area, policy and stakeholder intervention should concentrate on solving the cited constraints for sustainable food production and conservation of biodiversity. Keywords: Crops, Constraints, Diversification, Smallholders.