I am sorry for this delayed reply to your gardening question. The spring rush has brought a deluge of questions and we are working hard to catch up!
There are many flowers that fit that job description. Some of your options are: Impatiens, Begonia, Cardinal flower (Lobelia cardinalis), Oxalis, Mexican Petunia (Ruellia), Pansy, Foxglove (Digitalis), "Texas Gold' Columbine, Cyclamen, Flowering Tobacco (Nicotiana), Hosta, Tradescantia, Violet, Chinese Ground Orchid (Bletilla striata), and Wishbone Flower (Torenia fournieri).
If you have a fairly bright shade, you may do well with a hydrangea, or butterfly ginger (Hedychium coronarium and others). For a bit less light you might consider another ginger such as one of the Curcumas, Globba winittii (Mauve Dancing Ladies), or Kaempferia pulchra (Bronze Peacock Ginger). If her shade is really dark, you might need to look to the colored foliage of Caladiums to get some color into the spot.
I'm not sure what you mean by "magazines that sell these plants".
Thanks for the question. Best wishes for a wonderful gardening season. Please stop in again soon!
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