Low molecular weight carboxylic acids (LMW) play an important role in improving the bioavailability of soil nutrients. Non-exchangeable soil K, trapped between the interlayers of clay minerals, is an important source of K for plants in many soils. The objectives of this study were to determine the effect of selected LMW organic acids on the release of K from micaceous minerals and to investigate the root-induced dissolution of micaceous minerals in the rhizosphere of alfalfa and also the resulting mineralogical changes. A lab dissolution study was carried out using a completely randomized design with three replicates. Micaceous minerals including biotite, muscovite and phlogopite ( 60 ?m size) were reacted with 0, 500, 2000 and 4000 ?M solutions of oxalic, citric and malic acids for a period of 5 hours to 120 days. The amount of K released to the solution was determined with flame photometer. In addition, a pot experiment was carried out under the greenhouse conditions using a completely randomized design with four replicates. Alfalfa was grown on a mixture of mica ( 60 ?m size), as the sole source of K, and quartz sand. Four treatments were used including pure quartz, quartz + biotite, quartz + muscovite and quartz + phlogopite. To distinguish the effect of plants on K release, the same treatments were used in similar pots with no plant. Pots were irrigated with either distilled water or nutrient solution with or without K. After 90 days, plants were harvested and the amount of K in plant roots and shoots was determined by flame photometer. Also, the clay sized particles in the root zone were separated from quartz and analyzed with XRD. The rate of K release varied with the type of organic acids and also the kind of mica. Citric acid solution with a concentration of 4000 ?M was able to release more K from weathered minerals. The higher the concentration of organic acid, the higher the amount of K released. The amount of K released from minerals was in the order of phlogopite muscovite biotite. The kinetics of non-exchangeable K release from minerals consisted of two phases and was best described by Elovich, power and parabolic diffusion models showing that diffusion is the most important controlling process in K-release from minerals. Strongly coordinating LMW carboxylic acids enhance the mineral dissolution and weathering reactions through the detachment of surface complexes into solution. There was not any XRD detectable changes in minerals reacted with organic acids up to 4 months. Greenhouse results revealed that alfalfa was able to induce a significant release of interlayer potassium during cropping and this root-induced release of K had a great contribution to plant nutrition. X-ray diffractometery showed a strong vermiculitization of phlogopite and biotite in the rhizosphere of alfalfa. This suggests that the plant roots could facilitate the K release and also mineral transformation by depleting the