Ms Wood said she was "tickled pink" to win the grand prize.
"It's really about the joy of seeing a beautiful plant being appreciated by other people."
Ms Wood has her own laboratory where she germinates her own orchid seeds - but she describes herself as an "out of control hobbyist".
President of the Wanganui Orchid Society, Kath Bourne, said the show had been very well supported by the public.
"We had 350 through the door on Saturday alone. We had to open earlier than we expected because people were queuing up outside the door," Ms Bourne said.
She said blooms were judged anonymously in a dozen different categories.
Ms Bourne said the number of entries at the show was pleasing considering it had been a poor growing season.
"The weather hasn't been very kind to orchids this year," she said.