Answer: There shouldn't be any problems associated with using the wire hoops. However, if the pots are small, they will be prone to drying out, especially in an exposed position such as a balcony. It's also possible that some of your plants suffered from root rot or even snails grazing the stems and causing wilting.
Next time, try trailing ivy, grasses such as Carex oshimensis Evergold and Carex Frosted Curls, small pots of shrubs including variegated euonymus, and colour provided by pansies and primroses.
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