Question

Canna plant   I have a large pot of cannas.  They seem to be growing well but the leaves are turning brown around the edges and have not bloomed yet.  I winter them in a northwest window and they so well and then I put them out when the nights are warm enough.
I live in zone 5.  New leaves grow nice and green and lush and the older ones turn brown with in 3-5 days after the new ones come out.

Answer
Cheryl
Sounds like you have a watering and/or fertilizing problem...
Proper watering care is similar for most potted plants. Water your plant based on how much it weighs when thoroughly watered VS when they are ready to be watered again. Plants die from too frequent waterings (or going too long in between waterings), not from how much water you give them at one time. Pick the pot up and feel how heavy it is after watering it thoroughly. Don't water it again until it feels considerably lighter and the top of the soil is light in color. Depending on plant types, sunlight exposure and pot size plants will need water at many different rates from once a day to once a month or more.

You may need to divide the bulbs and plant them in new pots with new potting soil next spring.

Get to a local garden center and buy a good plant fertilizer for cannas. Ask them which fertilizer they recommend and read the directions before applying it...Plants do need to be fertilized periodically to stay healthy...
Start watering properly and your plant should recover quickly...
Hope this helps.
Rick in southern NJ