Will it kill the lily
You can. This will redirect energy back into plant growth, rather than reproduction.
This collection of articles will help you:
rs weak and falls off. what can I do to keep the blooms longer? I give them plan food once a week. I have some in the ground and some are potted.
You might be overfertilizing. Once a month is plenty. Make sure they are well watered and have plenty of sun. Also make sure there aren't any pests around the flower buds.
Here is more:
https://www.gardeningknowhow.com/ornamental/bulbs/canna/canna-lily-fertilization-tips.htm
https://www.gardeningknowhow.com/ornamental/bulbs/canna/managing-canna-lily-pests.htm
Growing Canna Cannova for the 1st time. Plants are growing strong & appear healthy however, once the blooms arrived they began what I call snake necking or shepherds hooking. Bowing their heads and exposing their necks instead of showing the faces of their flowers.?.? What gives? No other Canna variety I have, nor have ever seen does this. Snake necking Canna Cannova, why do they bow their heads?
It looks like a weight issue. Deadheading may help. Most of the droopy flowers are at the end of a long bud stem. Also, Cannova is raised from seed, not a rhizome. Also, check the amount of fertilizer being used. Generally a 10-10-10 applied once a month is sufficient.
https://www.gardeningknowhow.com/ornamental/bulbs/canna/deadheading-canna-lily-plants.htm
https://www.gardeningknowhow.com/ornamental/bulbs/canna/canna-lily-fertilization-tips.htm
It looks like your first frost is usually in late September and first killing frost is in October so I would go ahead and plant them. They grow quickly and you should have time to enjoy them before frost. Then after they die back, you can dig them up for storage, or if in a container, move them where it stays above 40 degrees F.
https://www.gardeningknowhow.com/ornamental/bulbs/canna/storing-canna-bulbs.htm
My mom recently gave me a portion of her established cannas that has been growing for over 10 years and has flowers about 7ft tall. I planted the bulbs with leaves that are about 1-2ft tall. I finally got one bloom that lived for a day but now all of the surrounding leaves are turning brown and dying. There was a new shoot that was growing (so exciting) but it only grew about 4 inches out of the ground and then turned brown and snapped at the base and died. I’m not sure if it’s the soil or the fertilizer I added to try to get them to grow. The fertilizer is for “roses and blooming plants”. I live in Texas and try to water all of my plants every other day. They get full sun where they are located. What might be causing this? Should I cut these leaves off? Also, notice the base of the stems are black?
It may be getting too much water or the soil is not well drained. Though they appreciate moist soil, it needs to be well draining. The roots could be saturated and unable to send nutrients up to the leaves and stems. It also could be fertilizer burn. Cut off the affected leaves. Make sure the rhizomes were planted properly and in full sun. Here are some articles that should help:
https://www.gardeningknowhow.com/ornamental/bulbs/canna/canna-lily-care.htm
https://www.gardeningknowhow.com/ornamental/bulbs/canna/canna-lily-fertilization-tips.htm
https://plants.ces.ncsu.edu/plants/canna/
https://plantpathology.ca.uky.edu/files/ppfs-or-h-01.pdf
It’s like the leaves have been “stitched” with thread to prevent them opening! When I do open them, they are moist inside with a black substance. What is it and what can I do?
It sounds like a canna leafroller at work:
https://aggie-horticulture.tamu.edu/galveston/weekly_Q&A/f&b_11.htm
Can you leave a Cana lily in the pot over the winter and put it in the basement?
You can move the container into the garage or basement for the winter if the temperature stays above 45 degrees. You have to be sure not to water it much during the winter, as too much water will cause it to rot. Just give it a little water once a month during the winter.
https://www.gardeningknowhow.com/ornamental/bulbs/canna/planting-cannas-in-pots.htm