We have synthesized large (0.7–1.0 mm) crystals of anhydrous, water-bearing, and Fe-bearing wadsleyite by means of growth from solution in the thermal gradient field. Nearly anhydrous (<68±4 wt ppm H2O) Mg2SiO4 crystals were grown using K2Mg(CO3)2 as a solvent at 16.5 GPa and 1700 °C. (Mg0.92Fe0.08)2SiO4 crystals containing 84±17 wt ppm H2O were grown using 92K2Mg(CO3)2-8FeCl2 as a solvent. Crystals of Fe-free wadsleyite with 1496±117 wt ppm H2O were synthesized at 1400 °C and 15.5 GPa by using 2KHCO3-Mg(OH)2 as a solvent.