A few years ago I bought some mistletoe seeds and affixed them to an apple and a Japanese maple tree. In the same season they put out their hypocotyl and holdfast, which greatly pleased me with the ease this was accomplished. Then nothing seemed to happen for couple of years, other than the Japanese is maple dying, thereby halving the available plants.
This year we have plants you can see, with developed haustorium swelling and good growth. An interesting aside to carnivory.
I have tried seeds from the Xmas bunches before, but have never had any success, those seeds were definitely not as sticky as the purchased ones. Whether it was the way they were stored or I got imported mistletoe that doesn't like our conditions or some other factor I dont know.