Answer: Since glads are not reliably winter hardy in colder climates, and since they can become crowded over time, most gardeners lift their glads every fall, clean them, sort them, and store them indoors for winter. This allows them to inspect the bulbs or corms for problems, and also allows them to amend and rework the soil in the planting bed.
Glads are very heavy feeders and do best in a very rich soil well amended with organic matter, so it is possible the soil in your grandmother's garden has become somewhat depleted over time. They also do best with at least an inch of water a week, meaning a moist (not soggy) well drained soil, so they may well be suffering from the drought.
It is also quite possible that your grandmother's glads have been attacked by an insect or a disease. You need to identify the exact cause of the problem in order to treat it but unfortunately, based on your description I can't give you a definite diagnosis. (If the plants are suffering from an insect or a disease, you really wouldn't want to plant them at your house because you would risk infecting the healthy plants at your house, too.)
You might wish to take a sample to your County Extension for a definite identification of the problem and suggested controls. Their telephone number is 536-5123. Good luck with your glads!
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