Geranium Guide

What Are F1, F2 and F3 Geranium Seeds?


When it comes to purchasing geranium seeds, you may at some point encounter seeds packets advertising F1, F2 or perhaps even F3 geranium seeds, but what do all these letters and numbers mean? Welcome to the world of plant breeding, where things can seem quite complicated, but not necessarily so. Deciphering these numbers is not difficult and with a few basic examples you can finally start understanding what’s really going on with those packets of geranium seeds. Learning more about F1, F2 and F3 geranium seeds may therefore help you make more informed choices so you know what to expect from your new geranium plants.

A Little Lesson in Genetics

To better understand F1, F2, and F3, a good place to start is understanding what the letter “F” stands for. F in this case stands for “filia” a Latin word meaning daughter.

So now let’s imagine your geranium plants as people. You have mother and dad and then you have their filial generations, in other words, their offspring. So F1 are the children, F2 are the grandchildren and F3 are the great grandchildren.

Now how easy was that to understand? Most likely, this little lesson will always stick in your mind when you will see those packets of seeds being sold at your local garden center or online.

However, there’s more into this. Knowing whether you are purchasing the “children, grandchildren or great grandchildren” of a certain variety of geranium is just a piece of information. At some point, you may want to know what happens with these generations of seeds and what to expect.

About F1 Geraniums 

An F1 hybrid is a geranium that comes from parents of two pure, unrelated lines. When you purchase a packet of F1 geranium seeds you’ll get plants that share valuable qualities gained from both parents and the geranium plant you will obtain from such seeds will produce flowers that are identical to the picture featured on the seed packet.

OK, let’s say similar, since many companies make pictures that are often too nice to be true for marketing purposes.

Generally, F1 seeds are more expensive than other types of seeds because of the work put into them in keeping the lines pure and yielding seeds that exhibit vigor and higher disease resistance.

About F2 Geraniums

Now, when the F1 seedlings grow into a plant, should the flowers self-pollinate (pollination between its flowers) or be purposely pollinated by hand, the seeds would be an F2 generation.

F2 generations are often a disappointment to gardeners because the plants are less vigorous and no longer look like the original flowers portrayed on the seed packets.

F2 are known for lacking uniformity and having great genetic variation in phenotype. This feature though makes breeders happy as their original plants cannot be replicated.

However, according to Thompson and Morgan, despite the claims made on seed catalogs, F2s may at times produce an acceptably high percentage of cultivars that are nearly identical to the F1 hybrids from which they derive, and they may get a nice percentage of the vigor and disease protection too! F2 seeds are generally cheaper in price than F1 but they can potentially be nearly as good.

About F3 Geranium Seeds

Once the F2 seeds grow into plants with great genetic variety, ideally plants with desired characteristics should be paired together so to yield an F3 generation. The seeds of F3 generations should pave the path to more genetic stability, reducing variation.

This process is called stabilizing and if the selective breeding continues, should one selectively breed plants that most resemble the origin F1 variety, there are chances that the plants obtained will reach a point where they will look almost identical to the original F1 variety, but capable of breeding true, a phenomenon that’s known as “dehybridation. ”