Answer: A blue flower garden can be a bit difficult because there are not many truly blue flowers. However, depending on how much purple you can tolerate, you may find some of the following appealing.
Annuals could include violas and pansies, forget-me-nots (<i<Myosotis sylvatica</i>), browallia, morning glory "Heavenly Blue", annual lobelia, ageratum, salvia such as Victoria Blue, and bachelor's buttons.
Perennials would include bulbs like Scilla sibirica and grape hyacinth, assorted bearded iris and Siberian iris, baptisia, Virginia bluebells, pulmonaria, assorted veronicas and salvias and campanulas, Vinca minor, delphinium, scabiosa, amsonia, stokesia, tradescantia, platycodon, flax (Linum perenne), the hardy geranium "Brookside", and Caryopteris.
The above is a sampling of plants you are likely to find. Your selection will depend to some extent not just on the color but also on the growing conditions on site; if you are new to flower growing you may want to look at a book or two to get you started in the right direction on soil preparation and plant selection. Enjoy your blue garden!
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