"Paulownia is highly adaptive species and grows well on many types of soils. Most appropriate and recommended are light, well drained and sandy soils with or without slopes. Most recommended are deep well drained soils with pH from 5.0 to 8.9.Avoid clay, rocky and soaked soils. Soils that are consisted from over 25% of clay and porosity under 50% are not recommended for Paulownia. Paulownia does not tolerate salinity over 1%. Young Paulownia plants develop well, when the soil depth is at least 1.5-2 meters".
Good points Dr. Andrew. Paulownia is one of the fastest growing trees in the world, capable of growth rates of well over seven feet per year as a seedling! But while it’s highly appreciated and cultivated in Asia, Paulownia has come to be considered an invasive species in the United States.