The diamond, signifying everlasting love, is the birthstone for April and when in the sun it radiates all the colors of the prism.  It also comes in many colors, blue, yellow, green, pink, etc, although the clear diamond is the stone for April.  The brilliance, radiance and many colors of the diamond, makes it difficult to choose a color of the month, so once again we are deviating to the flower of the month.  Research turned up several sources with different flowers all vying for April.  Some references preferred the tulip in either red or yellow.  However, most lists named  the sweet pea and daisy as the flowers for April.  The daisy is white and yellow and since we featured yellow for daffodils last month I decided we needed something different.  So, I chose sweet peas as the source for the April color of the month.  A quick look at pictures of sweet peas shows that they also come in a wide variety of colors from white to royal purple with all sorts of pinks, lavendar, lilac, magenta, and bright reds thrown in.  The 40% discount bin has pinks to purple  and reds this month.  The colors are vibrant and bright (although the sweet pea can also be quite subtle and pale in its color and shading). 
The history of flowers of the month and birthstones is linked to the Romans.  The Romans liked to give gifts and flowers and gemstones were some of the favorites.  In the past, it was not always acceptable to be frank or express feelings the way we do today.  Gemstones and flowers were given symbolic meanings which carried with them when they were given as gifts.  During the Victorian era a gift of sweet peas carried the hidden message "Thank you for a lovely time."  They could also signify blissful pleasure or in some cases mean good bye.