The first thing to know before saving any seed is whether or not the parent plant is a hybrid. Most petunia plants sold in garden nurseries are hybrids, so you cannot count on what type of petunia seed they will produce. However, non-hybrid petunia seed can be purchased, such as Balcony Petunia. These are also referred to heirloom or open-pollinated seed, basically meaning the seed from the plant should germinate and grow the same type of plant as the parent plant. Some people try to give special status to “heirloom” seeds, but I figure that anything that is open-pollinated has been around a long time. (click on any photo to enlarge) Be sure to check out my first short [40 second] tutorial at the end of the blog. :-)
There are some open-pollinated varieties of flowers that naturally have color variations within the seed. Balcony Petunia is one of these. That is, different colors do not in this case mean differences due to hybrid manipulation and unreliable seed production. In fact, you will reliably get the different colors from these petunias.
Petunia seeds are very tiny. If they fall to the ground, they will pretty much disappear from sight. The Balcony Petunias will self-sow, but petunias are one of those flowers that I usually have specific landscaping plans for. They seem to look best in a wide swath across a flower bed. It is easier to grow a couple of flats of petunia seedlings to be able to put exactly where I want them. The volunteers can bring unexpected joy to a few other places.
By the time there are some ripe seed pods on the plants, they are probably nestled lower on the plant, down under the flowers that are blooming all around the outside of the plant. Just a smidge of patience will help you find them. Just follow any stem down a ways, but do it gently so that you don’t accidentally knock seed out of pods that are staying upright or ready to pop if they feel a little bit of pressure. You will find seed pods in various stages of maturing and drying. You want the hard ones that haven’t opened yet. You might be able to find some seed in those that have opened if they haven’t succumbed to gravity. You may be able to see the the seeds sitting there like miniature caviar. (I don’t eat caviar, but that’s what they remind me of!) If they are ready, they will pour out like sand in an hourglass timer.
Some people recommend putting empty tea bags or home made mini-sacks over flowers to collect certain types of flower seed before it disperses. However, the petunias are an annual that blooms prolifically and constantly enough throughout the summer so that you can probably go out on any given day from midsummer to the first frost and find a few of the right kind of seed pods. There are enough seeds in 2-3 pods to save you a couple of dollars come spring, but you don’t have to limit yourself to that! It’s like shopping for free!
Below is my first ever embedded video in my blog. It is just a 40 second demo of me collecting petunia seeds recently. I’d love to hear what you think of it!