tx_flower_child said:I recently got some 'mixed zinnias' at a seed swap. I'm beginning to think that none of them are viable. Will take a picture later and see if you agree.
Hello TX flower child,
It's a definite possibility that none of those zinnia seeds are viable, but I will have to look at the picture. Unfortunately, I can't do a "pinch test" on any of them, but you can do that yourself. If you gently pinch a zinnia seed between your thumb and forefinger, you can feel whether the seed is thick enough to contain an embryo.
Another test you can do on a zinnia seed is to gently try to fold it in half. If it is empty, that can happen easily. If there is an embryo inside, the embryo will provide resistance to folding. Be gentle doing this. You can break a viable seed if you try too hard.
There are visual cues as well, but they are much more subtle and less reliable. They involve surface texture and subtle coloring differences, but are harder to explain. Visual cues can quickly tell you which seeds should be pinched or bent tested and which seeds are empty or too juvenile to have a developed embryo. If you examine a lot of zinnia seeds, you will eventually learn the visual cues.
Of course, detecting an embryo won't tell you if the embryo is alive or not, but the best way to do that is just plant the seed. However, there is no point in planting empty seeds.
ZM
