I have grown lilies in containers many years now. I like having them on the deck and I usually use bulk bags I get from Costco. They is reasonably priced and have a pretty good track record for me for being correct. I can then at the end of season donate to local gardens or neighbors or evaluate if it is yard worthy. Lol. Sometimes I'll keep one or two from a pot to locate in the yard, depending on what I have room for when the time comes and how excited I was about the lily. Our deck faces North, so there is less super hot sun, allowing the pots do better. Having tried a few different mixtures, the moisture retaining ones are one NOT to dry. Lilies hate that wetness. A local place near here has a very little peat (if any at all) mix that I use for both seed starting and pots and have success with both. The mix comes from some place in Illinois and the woman that owns the greenhouse said she has tried so many mixes for her thousands of plants greenhouse over years, and had the greatest success with it.
Overall, lilies hate pots I think. I have had rapid multiplication of asiatic lilies in pots, not all but some. It is as if they think I am killing them and they go nuts producing bulblets. Put them in the yard, same lily, little to no reproduction. Also the bulbs seem to shrink just a bit from spring to summer. I don't really care though. I still love the orientals next to my sliding door on the deck, so I can smell them in the house for weeks as they bloom. There's nothing like it. Mmmmmmmmm.
