Produced by FAO, IFPRI, and SAGE, Agro-MAPS (Global Spatial Database of Agricultural Land-use Statistics) provides annual sub-national data on crop production statistics (total production, area harvested, and yield for a number of crops). The dataset comes with spatial data on sub-national district boundaries.
The website is quite user-unfriendly for those who want to download the data, but essentially you have to do the following:
To download production statistics, choose the crop on the left column and choose the country on the top right corner. Then click TABLE on the top left corner. The window now shows annual crop statistics across sub-national districts. Then click the Excel icon to download the table in the CSV format.
To download the district boundary shape files, click "Download all the available data" in the middle-left box. The pop-up window shows up. Click "Download All Available Data". You are now requested to enter your detail. After filling in the form, you are asked to choose the country. Once you click the country and "Proceed" at the bottom of the page, the website starts compiling the data. Wait for a few minutes and you'll be asked where to save the data.
For country-level crop statistics, visit FAOSTAT.