I have several tree lilies. At end of season, do I cut stems back to ground level? At the moment they are in pots. The intention is to plant out. Those that have finished flowering, the leaves have turned brown in they went brown while flowering. I live in Hampshire and have very chalky soil.
Here is a link to help you.
https://www.gardeningknowhow.com/ornamental/bulbs/lily/growing-tree-lily-bulbs.htm
I have only just planted my bulbs. Will they flower this summer? Also, are they suitable for pots?
Yes, providing they are planted and receive the care needed, they will bloom.
Yes, you can plant in a container. Give the bulbs a nice deep pot and good a top soil/perlite planting mix.
https://www.gardeningknowhow.com/ornamental/bulbs/lily/growing-tree-lily-bulbs.htm
Should tree lily bulbs be split after a few years?
A general rule is if the plant is crowded and shows signs of less flowers or stunted growth, it's time to split your bulbs.
The best time to divide can vary, Fall is a good time, and gives the bulbs time to develop good roots.
Spring division can be done, but you may have less flowers until the following year.
https://www.gardeningknowhow.com/ornamental/bulbs/lily/growing-tree-lily-bulbs.htm
Do tree lilies require to be planted in a pot or restricted area to stop roots from spreading? Just planted 3 bulbs in border but not sure of their success this way. Have a magnificent lily growing at edge of patio with shingle over top.
They should not become invasive, so there is no reason to restrict their roots.
It's been a cold and somewhat damp spring this year. Last October I planted tree lilies, planting the bulbs about 7-8" deep. It's May 5th and I haven't seen any sprouts. Is it because the soil hasn't warmed up enough? There are no signs of animals digging them out.
I'm not sure what zone you are growing in.
Tree Lilies are hardy in zones 4-8 and can tolerate the warmer temperatures that are in zones 9 and 10.
The ideal depth for planting your Lily bulbs is 10 to 12 inches deep.
If you are in a cold zone, and the bulbs did not have enough winter protection and insulation, they may have froze.
Give it a few more weeks, it is still quite early. If you see no signs after that time, I would dig up one of the bulbs to check it's condition.
https://www.gardeningknowhow.com/ornamental/bulbs/lily/growing-tree-lily-bulbs.htm
I am going to plant some tree lilies in the mid of November. I live in London. I wanted to know if I can leave the pots with the bulbs outside as I have 12 large 40cm pots. I am going to bubble wrap the pots. Do you think that it will be ok or should I do something else? Thank you
Choose a sheltered location and add the insulation that you mention.
Also make sure you mulch the tops of the pots.
A garage location may be better if you have that option.
https://www.gardeningknowhow.com/ornamental/bulbs/lily/growing-tree-lily-bulbs.htm
I have two tree lilies and am not sure how to plant them. Are they better in pots or in the garden?
Even though tree lilies can get to be tall, they do just as well in pots as they do in the garden. So plant them wherever you like.
Tree lilies like partial sun and well draining soil. Plant your bulbs in autumn about 10 inches (25 cm.) deep, and water thoroughly.
You can read more about growing tree lilies here:
https://www.gardeningknowhow.com/ornamental/bulbs/lily/growing-tree-lily-bulbs.htm
You can read more about potted tree lilies here:
https://www.gardeningknowhow.com/ornamental/bulbs/lily/potted-tree-lilies.htm