Last year only one of my 4 varieties of asian pears set any quantity of fruit: 20th Century. I figured that the other 3 being only a year old were too new to set well, but this year the same thing has happened.

The varieties are Hosui, Seuri and Shinseki. Unlike the 20Cen, they require cross fertilization, they are within about 20 feet of each other and they all flowered profusely, but Seuri only set 2 or 3 fruit, Hosui set perhaps a dozen and Shinseki about 20. They were supposed to be timed to cross fertilize each other, but I wonder if the weather didn't prevent it from properly happening.

Any ideas?