Blue flowers are popular with gardeners. But finding a true blue flower can be difficult. A true blue color doesn’t occur in all species of plants; only about 10% of the plant species in the world have the ability to create blue flowers. There is no blue pigment in plants rather some plants have the genes for a complex process that changes red pigment in anthocyanins to blue and different plant species use slightly different methods to do this. If a plant species does not have the genetic “coding” for making blue color no amount of breeding can create it.
Some common garden plants are often said to be blue but in reality they are various forms of lavender and purple. These colors come from different genetic modifications of red pigments and are rather common among plant species. Blue daylilies for example are not really blue, despite deceptive camera practices and misleading descriptions. They are purple or lavender. Other flowers are dyed for the floral trade, that’s how you get the really blue looking carnations, roses, tulips, mums, orchids and certain other plants. White flowers are put in a blue dye solution and the color is absorbed by the flower stem. You may have done such experiments in school.
The blue rose
True blue, undyed roses don’t quite exist yet although they may soon. In 2008 Japanese plant breeders announced they had genetically modified a rose by inserting the genes that cause blue color in pansies. There was much hoopla and speculations about when blue roses would be on the market. But when the public saw the first blue rose they were not impressed. It looks much like the roses that catalogs now advertise as blue, which are a lavender color, but was horrendously more expensive. Plant breeders are continuing to work with the GMO modified roses and one day maybe a true blue rose will come to market.
A little sidebar: blue rose seeds are being offered on Craigslist and Amazon. While roses can be grown from seed, the result is not always very good and it takes several years for the roses started this way to bloom. Most named roses are propagated by grafting cuttings on hardy rootstock; landscape roses are started by cuttings and allowed to grow their own root systems. If the sellers of these blue rose seeds truly had seeds from a GMO modified blue rose (which is doubtful), what you got from growing a seed would be very variable and probably not even a good garden rose. The seeds may be from what is now on the market as blue roses, lavender shades, but even roses grown from those would probably not be great plants. Don’t waste your money.
Tulips are an interesting example of the intricacy of the blue genetic coding. Despite many catalog pictures and tulips with blue in their name there are no tulips where the whole flower of the tulip is true blue. There are however, species of tulips that have true blue color in markings near the base of the flower. It seems that breeding could magnify that bit of genetic coding so it would allow a totally blue tulip flower. But so far, despite centuries of tulip breeding, this has not been done. This could be an interesting (and potentially lucrative) project for those interested in plant breeding.
What flowers are true blue
You won’t find true blue roses (yet), daylilies, oriental or Asiatic lilies, mums, orchids, glads, dahlias, or carnations (and many other plants). These are plants often advertised as having blue varieties. Often “blue” listed in a plant description or name will really mean lavender or purple and for some people that can be just fine. But for those of you who are looking for true blue, whether in deep or pastel tints here’s a list of some plants where you can find the color.
Agapanthus, ageratum, ajuga, anchusa, aquilegia, azure allium-(Allium caeruleum), bachelors button(Centaurea cyanus),borage, caryopteris, ceratostigma(plumbago), columbine, brunnera, campanula, catananche, crocus, delphinium, echinops, erynigium, Evolvulus ( dwarf morning glory), forget me not (Myosotis sylvatica), grape hyacinths, Gentian, Himalayan blue poppy (Meconopsis betonicifolia), Hyacinths, hydrangea, iris of many types, larkspur, linum (flax), lithodora, lobelia, lupine, morning glory, pansies, penstemon, petunias, platycondon, primula, Scabiosa, stokesia, some salvias, veronica, and violas.
Good colors to enhance blue flowers are white and yellow. Silvery gray foliage is also a good enhancement. Avoid placing blue flowers against a dark backdrop as they will seem to disappear, unless the blue color is very pale. Orange and orange reds generally clash with blue flowers.
While true blue color may be rare in flowers you can find flowers in the color for almost any garden. Just be aware that every flower called blue won’t really be blue. Have fun adding blue to your garden this summer.
Here are some additional articles you may want to read.
Growing heritage flowers
How to grow trout lilies in the garden
How to grow the cardinal climber vine