Zantedeschia aethiopica

I bought my Arum lily about 6 weeks ago in a 3L pot and already in bloom. I planted it in a shady corner of the garden along with some Hostas, Heucheras and Hucherella. I have chalky soil but I dug a big hole with plenty of compost added in and mulch on top. It's been doing well watered well and growing along with the other plants in that patch. I noticed that this morning the flower has started to wilt, not sure if it's a cause for concern as I can't find info on how long the flower is supposed to be in bloom, plant looks in general good health. Would appreciate some info on flowering season and if some remedial action is required.