Germination is hypogeal and occurs in the spring following maturation. Because of a generally late spring emergence, seedling mortality from flooding is low. The seedlings do not tolerate prolonged submergence. Because of the large seed, young seedlings have high initial survivorship regardless of available light, drought stress, or herbivory. Water oak grows well on better drained silty clay or loamy soils and poorly on poorly drained clay soils.
Water oak is weakly to moderately tolerant of seasonal flooding.
It can survive up to several months of flooded soil, but mortality is high if this is a yearly occurrence. It germinates in shade but requires moderate light for development.