Daffodils did not bloom, so I assume they are planted too deep. Can I did them up now and replant immediately while I know where they are?
You can go ahead and dig them up, if you wish, but this may not be necessary. There can be other reasons for non-blooming in daffodils. In warmer areas, they do not get enough cold temperatures to be able to form a bud. They need 6-8 weeks of temps below 40F in order to form a bud and then flower in the spring. Therefore, it may be that this year they did not get enough cold weather (if you are located in a warm region). Here is more information: https://www.gardeningknowhow.com/ornamental/bulbs/bgen/how-to-plant-bulbs-in-the-south.htm
If you feel this is not the case, the other possibility is that the ground is lacking phosphorus. Without phosphorus, the bulbs cannot form a bud as well. Here is more information on that:
https://www.gardeningknowhow.com/garden-how-to/soil-fertilizers/phosphorus-plant-growth.htm
I had to remove over 100 daffodil bulbs from an area that was going to be dug up for basement work. They are done flowering and I removed the spent blossoms but the foliage is still vital. Should I plant them in a new space right now or should I wash them off and let the foliage die off and plant them in fall?
They need the foliage to help generate energy for next year's blooms. If you can replant them now, I would, with the leaves intact. But daffodils are pretty hardy. If you need to store them until fall, I would let the foliage die back, dry them out and store in a cool dark place.
Will removing the flower and stem from the plant after it blooms cause the plant not to bloom next season? I unknowingly pulled the dead flowers and their stems out of some of my plants. I am really hoping this will not affect them because they were beautiful this year. If I messed up big time, what (if anything) can I do to correct this?
There are many reasons why bulbs do not come into bloom. One of the most common is not having enough energy to form a bud. Bulbs depend on their foliage for energy. Unfortunately, some people resort to cutting the foliage back rather than allowing it to wither away naturally. If so, this could result in non-flowering bulbs. If you have a bulb that has produced numerous offsets, this could be another likely cause for non-flowering. Another common cause for non-blooming bulbs is the lack of sufficient light. Check the growing requirements to ensure the bulbs are located in an area with plenty of sunlight. Finally, check to see if your bulbs are simply overcrowded. Oftentimes, when plants become overcrowded, they fail to flower properly. Should this be the case, division may be needed.
After they have bloomed, can forced daffodil bulbs be used again?
Yes, this article will help:
https://www.gardeningknowhow.com/ornamental/bulbs/bgen/how-to-plant-a-flower-bulb-in-your-garden-after-winter-forcing.htm
How should I store Narcissus bulbs?
This article will help you:
https://www.gardeningknowhow.com/ornamental/bulbs/bgen/preparing-bulbs-for-winter-how-to-store-bulbs-for-winter.htm
I live in Indiana. We are landscaping a sloping section of our yard. There are several clumps of daffodils, probably 100 bulbs, I don't want to lose them. Can I just dig the clumps and transplant them now, or do I need to store the bulbs and plant them in the fall? They bloomed this spring and the leaves are still green.
They are pretty hardy and they won't be harmed by moving right now and will also still have a high likelihood of still blooming next year as well. Make sure when you move them, you leave their leaves intact.
With bulbs other than daffodils, you can move them this time of year, but they may not bloom next year due to the stress of moving, but daffodils are made of hardier stuff.
I planted bulbs last year. This year the leaves came up from tulips and daffodils, but with no blooms. I used fertilizer and just discovered not to. Have I killed my bulbs? Will they bloom if I stop using fertilizer?
Oftentimes these plants will not flower but every other year, and in southern climates may not bloom at all without a significant cooling period. In fact, in warmer areas, they are often treated as annuals. I am sure you did not kill the plants, however. Adding little phosphorus to the soil may help them.