Question
Will lilac bushes grow in Hawaii?  We live at 900 ft. on the rainforest (east) side of the Big Island.

Answer
Hi Bett,
Thanx for your question.  Lilacs require extended periods of temperatures of 40F and lower.  They are a deciduous shrub and require a long period of winter dormancy and cold-temperatures to regenerate and bloom.  If you plant a lilac in Hawaii, it will eventually wear itself out (by not being able to go dormant) and die.  This will probably only take about 18 months to happen.  I hope this helps.
Tom