Answer: Some houseplants that tolerate lower light include those listed at the following page. If you click on the name you can see a photo and additional information.
Keep in mind that even the low light tolerant houseplants will need some decent indirect light, so if it is truly dark you may want to look into silks, some of the new ones are very realistic -- especially if they are in a fairly dim spot.
As far as the mailbox planting, there are some things you can do to try to help with the drainage that would allow you to grow plants more easily. One is to add ample amounts of organic matter such as compost, well rotted chopped leaves, or well aged stable manure/bedding (you would do this regardless) plus some coarse sand or fine grit (specifically for the drainage). Work these into the top six inches of soil. Doing so will create a slightly raised area that will drain better than the surrounding soil. If you continue to add organic matter every year and also use an organic mulch each year you will be able to maintain a raised bed. YOu may use an edging if you like but it is not required, keep a sharp steep side. Some perennials you could try if it is still wet would include bee balm (Monarda), asters, Helenium, perennial Hibiscus, and perennial Lobelia. Good luck with your garden!
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