How do you tell if a tree is male or female?

Question

I was reading through some of the questions on fruit trees, because I've been thinking about getting some blueberry bushes and cherry trees, and I see a lot of people mentioning that the trees don't self-pollinate, and that you need a male and a female tree to get fruit.

I thought that flowers had both male and female parts, and that the pollination was just from bees transferring pollen to other parts of the flowers. But to me, that sounds like there are trees that have flowers with only female parts, and trees with flowers that have only male parts. And then trees that self-pollinate that have both flowers.

If there are trees that are only male or female, then how do you tell what sex of tree you have? Do you have to look at the flowers to know?

Answer 1

Some trees have a single "gender" but many do not. The way to tell is to see if the male (pollen) parts are present on separate flowers on different trees from the "female" (ovary - ie, infant fruit) parts. Also, you should be aware that issues with pollination may not always be related to needing both "male" and "female" trees around - sometimes a tree has what is called a "perfect" flower (with both male and female parts) but because the pollen from the male portion does not ripen at the same time or is in some other way incompatible with the female portion, it may require others of its kind around with different pollination times in order to set fruit. Apples are that way, sometimes, as are hazelnuts. This is why you often see recommended pollinators listed for certain apple varieties.

Bushes are the same way - some have only one gender as well. So do some fruiting vines, like Kiwi, which for the most part require one male kiwi for every 8 females. There is at least one self-fruitful variety - Issai. But even those fruiting plants that are self-fruitful will often be even more productive with additional pollinators.

A little research on the type of fruit trees you have should turn up any issues of flower gender and suggestions for providing the best pollinators/pollinating environment so that your trees can be as productive as possible.