What about a child safety rail I know they have ones that you slip between the mattress and foundation. During the day take it off slide under bed for storage

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Tried to post a link a quick search found one on target site

How about a long basket or crate at the foot of the bed to catch the quilt? Also useful for holding pillows that live on the bed in daytime but aren't used for sleeping.

Another option, depending on your bed construction, could be to create a taller footboard by replacing your box spring with a thin platform.

I am a seasoned registered nurse and worked for years in the prestigious Duke University Medical Center Allergy & Immunology Department. Dust mites are all over your bedroom: on the floor, in your pillows, carpets, curtains, mattress etc.; they are not just “on your floor”. To keep them minimized, it’s best to wash your bedding in hot water weekly. Have you thought about using a few large safety pins to pin your quilt to your sheets so it is secured near your feet?

I have a velvet bench at the end of my bed and it catches the down comforter that i keep folded at the foot of my bed. I think the success lies in the friction from the upholstery on the bench and it keeps the comforter more or less from hitting the floor. I also have my roomba run in the bedroom every day after i leave the bedroom for the day, it keeps dust to a minimum. My son has allergies and I do the same for his room. It helps.

I have significant dust mite allergies - dust mites are everywhere, in your bedding as well as your floor. So if you are dust mopping/damp mopping your floors frequently, I'm not sure how the bedding is accumulating more dust mites from the floor as you would get by having it on/near your body. Do you get cold when the blanket falls to the floor? If not, I'd just fold it and take it off your bed at night. If you do get cold, you might want to try a lightweight weighted blanket with a removable/washable covering...that should help.

As said above either a pice of furniture at the bottom of the bed, or add more friction between comforter and sheets (flannel sheet would be a 2nd option), or affix the quilt to the sheet with large safety pins or maybe binder clips. or maybe a less slippery quilt such as a velvet one.

I do all the allergy things - HEPA air purifier; mattress & pillow protectors; washing sheets weekly & changing pillowcase several times a week; no curtains; hardwood & tile floors (it took a lot to find an apartment with them). However, I haven't damp mopped the floor (just vacuuming) - I'll start doing that. The flooring buckles easier so I have to be very careful with even dampness on it.

I now see that the problem is my slippery cotton bedding. I have no-wrinkle sateen cotton sheets (that feel so good to sleep in) and then a thin sateen quilt that looks like it is polyester even though it is cotton. I love, love, love the quilt. It is from Macy's Hotel Collection, is very white and I worry about staining it. Maybe I should get something more practical. In terms of slipperiness, I am just realizing I am two steps away from all satin bedding!

I am going to try several things you suggested & then let you know.

My body does not regulate my internal temperature very well. I wake up if I am a little hot or cold. If I have my lightweight quilt on, sometime I suddenly overheat. (My sleeping was a wreck during menopause.) I'm going to try different temperatures, too.

Many thanks to all of you!! And thanks for helping me look at this in different ways.

Another option is a California King quilt or blanket which is longer and then you will have ample length to tuck it in very well at the foot.

Here is another question.

Are you symptomatic with your allergies when the quilt falls on the floor, or are you just worried about it so that's why stick the quilt in the drier every day?

If you are that symptomatic, you might want to talk to your physician about medication.

Vacuuming a wood floor can be tricky because depending on your vacuum type you may be spreading dust around the room too.

I love Swiffer because the covers are disposable.

You can also use on the wand paper towels or even cloth rags and re-wash them if you don't want to buy the Swiffer brand covers.

Does frequent dryer time wear it out? If a plainer cover than a quilt would work, you could display/ hang yours on a 'ladder' of metal or wood.

Try a smaller quilt. I have a queen size bed and use a baby size quilt. It usually stays on the bed, and is easy to fling on and off every hour or two! It stays on the best if its well worn and not stiff. Then it gets folded and put on a bench during the day. Flannel sheets would also help.