Noun and の adjective
めばな
ヒマラヤスギは、樹齢30年を超えないと雌花を付けません。
You can’t cross a 30 year old Himalayan Cedar with a female flower.
A female flower is a female flower!
The readings for this word are both kun'yomi readings. You learned them when you learned the kanji, so you should be able to read this on your own.