In the autumn of 2009 I bought and planted one foxtail lily, and in 2010 it flowered with one stem. This year there are two shoots coming up, so I imagine it multiplies.
Hello Green fingerd will,
I've grown quite a few varieties of foxtail lilies. Some rootstocks produced many flowering shoots by their second summer in the ground. Others only one or none. I do hope you get a lot. They can be really spectacular.