What causes the leaves of my cup flower to turn brown and brittle?

Question

I don’t know much about this plant, given to me from a co-worker’s garden 5 years ago. Early in summer, before the yellow blooms open, the leaves turn brown and brittle, from the bottom of the stalks up.

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Answer 1

This could be due to improper watering.

Make sure the soil is adequately moist; not dry or soggy.

https://www.gardeningknowhow.com/ornamental/flowers/cupflower/growing-cupflower-nierembergia.htm