163. The petunia

The lesson, step by step

1. When and where

   Comstock calls petunias “determined bloomers” that flower until killing frosts, so they are good for a fall lesson. Use a garden bed or pots; part of this lesson happens at twilight.

2. The leading thought

   The petunias have an interesting history being native to South America. Their flowers are fitted by form and mechanism to entice the hummingbird moths as visitors, and to use them for carrying pollen.

3. Colors and markings

   What colors do you find in the petunia flowers? If striped or otherwise marked, what are the colors? Are the markings symmetrical and regular?

   Sketch or describe a flower, looking into it. What is the shape of the corolla-lobes? How many lobes are there? How are they veined?

4. The toothpick test

   Thrust a slender pencil or a toothpick into the tube of a fresh flower. Does this spread the anthers apart and move them around? When it is withdrawn, is there pollen on it?

5. Leaves and stems

   How do the leaves feel?

   They are soft and a little sticky. Look at the hairs with the lens.

6. At twilight

   Visit the petunia beds in the twilight, and note whether there are any insects visiting them. What insects do you find visiting these flowers during the day?

   Look for a fast, hovering moth with a long tongue. Use the flashlight only briefly so you don't scare it.

7. Nature notebook

   Draw a petunia looking into it and from the side. Find South America on a map and write one line about where petunias came from.