What is "heteroblasty"

n. (context biology botany English) The state of being heteroblastic

Heteroblasty is significant and abrupt change in form and function that occurs over the lifespan of certain plants. Characteristics affected include internode length and stem structure as well as leaf form, size and arrangement. The earlier and later stages of development are commonly labelled as juvenile and adult respectively, particularly in relation to leaves.

The term was coined by German botanist Karl Ritter von Goebel, along with homoblasty for plants with leaf characteristics that do not change significantly. Leonard Cockayne observed that heteroblasty occurred in an unusually high proportion of tree species native to New Zealand.