New data on the growth rates of d-xylose crystals in aqueous solutions either devoid of d-mannose or containing this sugar as a co-solute and in hydroalcoholic solutions, obtained in a batch isothermal laboratory-scale seeded crystallizer, are reported. Growth kinetics have been evaluated from successive crystal size distributions (CSDs) recorded by means of a laser light scattering size analyser. The experiments have emphasized a broadening of CSD during growth in any type of solution and a decrease of the overall d-xylose growth rate due to the presence of ethanol or d-mannose. Growth kinetic models have been identified from direct analysis of oversize cumulative number CSDs and from the population balance equation. Solutions to population balance equations have proved that growth rate dispersion rather than an intrinsic dependence of the crystal growth rates on crystal size is responsible for the variability of growth. A time-averaged growth rate equation as well as a growth rate diffusivity parameter have been identified in each type of solution.