Chances are good that pollinators were still around when the flowers were in bloom in your zone. Otherwise, I don't think most would set seed at all.

Just do a germination test if in doubt- try to sprout a few in a cup in your house.

Karen

Hi Leslie,
"Are seeds only viable when they've been pollinated?" It is not a ridiculous question!
The answer is it depends on the plant. Some plants have flowers with all the parts need to make their own seeds. These are called perfect flowers. An example of a plant with perfect flowers is tomatoes. You could grow tomatoes indoors with out insects and get fruit. You do need vibration as wind would cause to make the pollen move inside the flower, but that's all you need.
Some plants do need to have insect pollinators to set seed. Most often it is just a flower to flower cross and one plant full of flowers will do. Often times on plants like this, early blooms, blooms during inclement weather and possibly late blooms will have few good seeds because of the absence of pollinators.
There are even a few plants that need a second similar plant nearby to set seed though these are not the usual things we save seeds from. A good example of this is apples. An apple needs a different cultivar nearby to set fruit to make seed. It is its way of creating genetic diversity. So that is why apple seedlings never come true to the parent.

Seeds can develop in cool weather just fine. There's a few big ones like beans that have trouble. It is not because of pollination(beans also have perfect flowers), it is because of the seed trying to loose moisture and harden.
Good seed will always be hard. So if you say save seed from Purple Coneflower, you will find lots of seeds in a seed head. There will be good ones and bad ones. Ones that are not plump and hard are no good. Bad ones will be smaller possibly thinner and will collapse under pressure of you fingers.
If seed is bending, squishing, turning to dust, etc. when pressure is applied between your fingers, they are definitely no good, and not worth a germination test. Most annuals and some perennials germinate easily at room temp with a paper towel test and you can check your seed, but if your seed is hard, you should be fine. Some perennials need a cold period to germinate so doing a quick germination test isn't feasibly, but again if the seed is hard, you should have good seed.
Usually hard seed that doesn't germinate is old, has been exposed to high temps and humidity in storage for too long, has unusual germination needs(very rarely,) or is one of the few seeds that need to be stored moist(some woodland perennials.)
That's more of an answer that I think you asked for,lol, but you can see your question wasn't very stupid or basic : )
Remy

Absolutely fantastic answer, Remy.

Thank you so much.

I read the part about Tomato flowers earlier this year because my father wanted a couple tomato plants so I had to do my research on how to care for them. A few good shakes on the stakes and couple light thwacks on flower stems was daily ritual. Same didn't work for Pepper plants in same family so I tried pollinating with paint brush method. Just not enough prolonged heat and sun this year for those peppers.

Now I see the wisdom of segregating seeds by date of collection and not wondering why some in bunch don't germinate.

Not all seed being viable on the same Echinacea cone is a revelation.

Had "hard seed" experience with Larkspur that never germinated this past sowing season. Know they like to be "fresh" for best germination but that's hard when you can't get a patch started. Trying again this year with seed from another source. Read seed would stay fresher longer if kept in fridge until sowing. Don't know if that's general rule for optimal storage conditions for most seed or particular to seed that likes to be "fresh" when sown for best germination.

Thanks again for fabulous explanation. I appreciate your taking the time to provide so much information which I like having.

Leslie

yup all seeds need to be pollinated. Even if they are capable of being self fertile, the vibration is to pollinate the flower. Pollination just refers to pollen moving, not necessary via insects.

the embryo inside the seed will only develop if pollination occurs...think of babies, you need male+female. if pollination happens, the seed will most likely have a 'hard' part where the embryo is (in humans the womb expands). If no pollination takes place, no embryo develops inside the seed (in humans, the unfertilized egg is passed through as usual).

I just find it easier to explain with the human analogy, not sure if it's what you're looking for. Remy and Leslie are both absolutely correct, but I just like throwing in some more science to confuse you ;)

How embarassing...at my age I need a lesson in fertility...
LOL. Thanks, origami_master. Got it now...they all need to be pollinated but not necessarily by pollinators.

Going to try baggie test on seed batches I collected. Should do that with any seed I use although a couple might not be fertile yet others in packet/batch may be.

This seed sowing and mother nature are good at crap shoots. :)

Just to through in some more confusion, seeds are not pollinated. If the flower of the plant does not get pollinated, no seeds are produced at all. It goes like this:

pollination >> fertilization >> sexual reproduction >> seed production.

Many other factors will determine the viability of the seeds which are produced.

Leslie, There's a book called "Sex in Your Garden" by Angela Overy that is not only hysterically funny, it's considered botanically accurate. Check it out on Amazon or your favorite book website. It's paperback that offers a unique perspective and explains in layman's terms the reproductive processes and goings on in your flowerbeds.
Eileen in CT

Donn...thought of you when I was trying to get seeds from my Hakone grass. Have no idea how I'd know if those were fertile.

"...a book called "Sex in Your Garden" by Angela Overy..."

Please tell me her surname is a "nom de plume" in spite of spelling variation...LOL.

Yeah, I thought it was a joke as well until I read the testimonial about the book on the back of an old gardening calendar someone left behind at the office. It was written by some respected horticultural authority with letters after his name so it caught my eye. Then I read the book myself and was amused and informed simultaneously.