Wednesday, August 29, 2012

Petunia The Musical Magical Flower

Species name: Petunia x hybrida 'Supertunia Raspberry Blast'

Common name: petunia

Location: Ontario

Surprisingly enough, I learned today that this plant is native to South America! All of my South American readers will probably be wondering why this is surprising, and to be honest I have no idea. I just always figured it was from Asia and never really gave the plant much thought. If I had of thought about it, I would have very quickly realized that this plant must be in the Solanaceae or the tomato family (which it is), and that most of the members of this family originated in South America. So not all that surprising after all!

This genus Petunia (it's always nice when botanists decide that a Latin name sounds good enough to make it the common name of the plant, too) is comprised of about 65 species, but only the ornamental hybrid is grown widely around the world. There are four main types of hybrids that are classified based on growth form: the large flower form, the multi-petal form (where the stamens have been bred to be petals due to a genetic mutation), the miniature form, and the creeping form. The fact that this plant can creep at all poses a serious risk to native wildflowers, and so that form should be planted with extreme caution around naturalized areas since there's always the potential for escape. This plant would be incredibly unlikely to survive the winter, but given the right conditions it just might.

The majority of petunia flowers, like many members of the Solanaceae, are most fragrant at night. In fact, most people would argue that petunias have no smell at all since they never experience the nighttime fragrance. The only notable exception to this is also the exception to the method of pollination for petunia flowers: the species Petunia exserta. This species has brilliant red flowers that are pollinated by hummingbirds, and consequently have a strong sweet odor even during the day.

A word of caution to the farmers out there that also enjoy ornamental plants around their homes: it is strongly suggested that you avoid petunias as an ornamental plant. They are one of the main food sources for a moth named Helicoverpa zea, which also lays its eggs in the flowers. The larvae emerge from the eggs and completely consume the flowers, leading to a rather nasty-looking plant. This in and of itself isn't any danger to an agricultural crop; it's once the larvae leave the petunia flowers looking elsewhere for food that they become a really serious pest. If found on corn, the common name of the insect is the "corn earworm," if found on tomato it is the "tomato fruitworm," if found on cotton it is the "cotton bollworm." This pest causes thousands of tonnes of crops to be lost every year around the world, but especially in North America. This illustrates one of the many issues surrounding non-native plants as garden ornamentals: once you plant the non-native species, you never know what it's going to bring with it that can devastate an ecosystem. The way that this species is controlled now is through the use of genetically modified crops that contain the active toxin in the bacterium Bacillus thuringiensis, and are known as Bt-crops.