Christopher is about one metre which is over 3 feet. Look at the website Polly provided for information. A 4 inch lily would not appeal to me it would likely get stepped on.
I have already potted up the lily bulbs in Miracle Grow using gallon pots. I keep them under lights until it is warm enough outdoors then get them use to the outdoors. When I get time they then get planted. I have done this several times and my lilies works well for me and my zone 4 climate. It is raining today and we may have some snow next week.