Trilliums usually flower early in the Spring and stick around for awhile however, if they are under stress ( drought, transplanted etc.) they might go into early dormancy. So it's possible that your trillium is just going into early dormancy which means it's very likely that it'll be back next yr. Where did you plant it? According to this source, these trilliums are fairly hardy and tolerant of different conditions.

Here is a link that might be useful: T. foetidissimum

Agree with adidas, but also you may have aquired T. cuneatum instead of what the label said. It goes down after flowering, but most of the others I have don't, including T. foetidissimum. They hang on for a while as long as we have rain.

I do feel confident that it's T. foetidissimum since I bought it at Tony Avent's nursery, Plant Delights. But, I think you may have hit the nail on the head in that it has been dry. I have watered it from time to time, but perhaps not enough. I have very sandy soil and I did amend heavily with compost before I planted it, hoping that will help. Should I give it more adequate moisture to insure its survival if it's still viable? I really do hope it will come back next year. Thank you so much for your advice.

Rhizomes rot with too much moisture, so probably at this point you can just hope for normal rain.

Trilliums have been very resilient for me; I haven't lost too many. Even when the deer eat the tops, they usually come back the next year.

Don't fail to mark the spot so that you don't dig into the area and plant something else on top. I have cut some of the rhizomes when I forgot I had Trilliums in a certain spot. They come back, in doubles, but they don't bloom again for several years. BTW, that is how some nurseries increase their stock.

I wish you luck.

ncrescue,
Thanks so much, too, for your valuable advice. So they don't bloom every year? I will be sure to mark it...I hadn't thought of that. Tony said it takes them 5 years to get a plant ready for market.

Some books save five years, some seven. At any rate, that is why they are so expensive. Most seem to bloom every year, but some things take time off. I have too many to be able to say if they all bloom each year. I am getting babies now from the seeds that the ants dropped. Exciting!

Some of my pink lady slippers go "away" for up to five years, then they return and bloom. Others come up year after year but don't yet have the energy to bloom. Then suddenly, there is the lovely flower.

Guess that is why I like natives....always a mystery there.

I will try to remember to revisit this thread next spring and let you know what happened. :)