All grandiflora petunias are hybrids. The smaller multiflora petunias may not be although it doesn't matter. It is the method of fertilization and pollination that makes them come true. If a petunia is open pollinated the flower from that seed could be any combination of all the flowers the insect that pollinated the flower had visited.

Seed that is sold is carefully hand pollinated with the same variety of flower and then covered with a gauze bag until the seed is ripe. Then it is collected and packaged for sale.

Does anyone here know for certain if Phantom Petunias >(BallFloraPlant - chartreuse & black starburst) are commercially propagated from F2 seed? I found some really cool sports at a local garden centre: the phantoms have obviously not bred true, because the colours are wonky, starbursts are inconsistent and some of the flowers have leopard-spots. (pic stolen from burpee)
The spotted flowers are just the neatest thing, and I can't find anything like them through google.

From what I've read (and seen) the color pattern of the flowers on Phantom Petunias are stable, but only with moderate (not overly hot or cold) temperatures. I've seen this in person when a friend grew this variety last summer. In the high heat and humidity of summer many of the flowers did not have the star pattern. Some were striped, some solid colored (yellow OR "black"), and some were just slightly starred.

The flowers you saw had probably been produced during extreme weather conditions thus the spotted/unstable star pattern(s) you saw.

I doubt that F2 seeds would produce many plants with flowers in that near-black/starred color range.

The seed companies will produce vanity photos for all the various flower and vegetable varieties. This SELLS the seeds and plants for them. Therefore, you probably won't find too many pictures that show the variations. :-)

Chris

I have bought 2 small pots at 4 bucks each and both are doing great they have kept there color and star shape

chris_in_wv That's really interesting. I knew something wasn't quite right and I had read that the cheaper F2s were unstable, but that explanation didn't make perfect sense, so I had also wondered if it was a virus or satellite. I bought these baskets on clearance, in really rough shape, from a parking-lot plant vendor. They obviously haven't been consistently watered and the weather's been all over the place this summer, so temperature extremes are a given. I wonder if I could replicate the spots by taking regular Phantoms and stressing the plants (just as an experiment).

chris_in_wv Oh, do you know anything about the specific characteristics of the parent lines for the Phantom F1s?

After reading your post, I managed some more targeted searches about petunia genetics, and found that they are prone to induced mutations (through the use of radiation), which has lead to the development of interesting new colour traits. Not exactly the same as the temperature-induced instability, but still quite cool.

I can say, without question, that these are NOT propagated from seed. The only way BFP (or any other breeder) can maintain the purity of these patterns is by asexual propagation - cuttings specifically for these.