Do these plants multiply? I have groups of thin leaves coming up in the bed. They look like gladiolus leaves only smaller and in bunches.
Yes, the corms produce a baby corm or cormlet.
The links below have more information.
https://www.gardeningknowhow.com/ornamental/bulbs/gladiola/propagating-gladiolus.htm
https://www.gardeningknowhow.com/ornamental/bulbs/gladiola/care-of-gladiolas-how-to-grow-gladiolas-in-your-garden.htm
https://www.gardeningknowhow.com/ornamental/bulbs/gladiola/storing-gladiola-corms.htm
My glads after the flower dies has a bulb growing out of the flower petal area. Is this how they reseed themselves?
Your Gladiola has produced seeds.
Here is an article to help you.
https://www.gardeningknowhow.com/ornamental/bulbs/gladiola/gladiolus-seed-pods.htm
Once the flower has died, where should I cut it? Will it grow another flower or is it done for the season?
This article will help you properly dead head Gladiola.
https://www.gardeningknowhow.com/ornamental/bulbs/gladiola/deadheading-gladiolus.htm
Do they only send up one bloom shoot per plant? Then are they done blooming?
In most cases their will be one flower spike.
Here are some links to help you.
https://www.gardeningknowhow.com/ornamental/bulbs/gladiola/care-of-gladiolas-how-to-grow-gladiolas-in-your-garden.htm
https://www.gardeningknowhow.com/ornamental/bulbs/gladiola/storing-gladiola-corms.htm
https://www.gardeningknowhow.com/ornamental/bulbs/gladiola/deadheading-gladiolus.htm
How long can you keep bulbs?
Kept at the proper temperatures and storage conditions they can survive for quite a long time. I have a garden friend who says she can store them for at least a year with good success.
Here is some links with more information.
https://www.gardeningknowhow.com/ornamental/bulbs/gladiola/storing-gladiola-corms.htm
I decided to check online a little bit too late for 2 plants. I cut off the long flowering part after the flowers bloomed and died cause I saw seed pockets in each slot. They hadn't turned brown and I didn't wait the 4 to 6 weeks. What do I do now with that long stem?
Just allow the stem to stay in the garden until fall when the greens die down naturally.
Here is a couple of links to help you.
https://www.gardeningknowhow.com/ornamental/flowers/gladiola/care-of-gladiolas-how-to-grow-gladiolas-in-your-garden.htm
https://www.gardeningknowhow.com/ornamental/flowers/gladiola/storing-gladiola-corms.htm
I have planted gladioli, for the first time, and didn't realize how high they would grow. Can you repot these while they are flowering? I think my pot is too small and I would like to know if I can put them in a deeper pot, please. Kind regards Sarah
Thank you, that was very helpful ?
Sure, you can repot them, just be sure to water them sufficiently once they're settled into their new pots.
This article may help you transition your Gladiodus bulbs into new pots:
https://www.gardeningknowhow.com/ornamental/bulbs/gladiola/growing-glads-in-containers.htm