After the plant is stressed, bagging or doming it is wise and will help. However, you have the plant seriously over potted. With a pot disproportionately large it is difficult to keep the soil from staying too wet. Ideally the pot size should only exceed the spread of the roots by about 1/2 inches to an inch at most, which leads us to the usual saying that the pot size should be about 1/3 the size of the plant. That is more applicable with an adult plant than a baby, however.

I would suggest repotting it into a small pot that is less wide than the spread of the leaves. Also, your soil looks heavy and has little perlite in it. African Violet roots thrive best where there is tons of light airy soil. I use 1/2 potting soil mix with 1/2 perlite myself though usually 2/3 soil mix to 1/3 perlite can also suffice.

If you get a lot of condensation accumulating on the inside of your bag, open it slightly or cut tiny slits to allow some evaporation. It does not need to be entirely sealed. After it's been bagged about a week you should be able to start opening the bag slightly and getting the plant re-acclimated to your normal open air growing conditions. Provide the brightest light you can that is not full sun and it should do well.

As for the broken leaf? Simply stick the stem tip down into a tiny bit of soil and bag it separately. It will need to remain bagged or domed for a couple of months but if the soil is only damp and not wet, and if your light is bright enough, your odds of it growing entirely new plants are not bad at all!

For more information on propagating African Violets from leaves, or potting sizes, or potting mixes, Google is your friend. Keep reading! Once you learn a few basics, they really are pretty easy to grow and enjoy. ;)

Here for example is a baby African Violet called 'Rob's Macho Devil'. It measures about 1.5 inches wide and is shown here in a 2 inch pot, started from the mother leaf that is still there on the right. Even this can be considered too large a pot for the baby so you need to be very careful that the soil is only damp, not wet. If I shake this pot firmly up and down, no water should drip out of the drain hole in the bottom. You can see that there is a lot of perlite in my mix and over time with watering some of the soil washed away to make it look like there is more than I actually use. I do wick water so the 1/2 potting mix to 1/2 perlite is a good ratio for drainage. You may use a bit more soil and a little less perlite if you hand water.

Here is the same plant several months later. Still in the 2 inch pot though I have repotted it to refresh the soil. 'Rob's Macho Devil' is a semi-miniature that I easily maintain at around 4 to 5 inches wide as a fully grown adult plant.

You can see the thin yarn wick hanging out of the bottom of the pot. If this were a larger growing standard, every time the plant begins to get slightly pot bound (about once every 3 months, slightly longer if your plants are grown cool or in low light) I would repot it and bump it up to a slightly larger pot. Eventually a 12 inch wide plant, with older leaves removed, should fit into about a 4 or 5 inch pot depending on the size of the root spread. The same plant without the older leaves removed might easily reach 14 to 16 inches.

As a general rule (with some exceptions) when the plant starts to get a little pot bound, that is the trigger for blooming. Once it has bloomed, any old flowers or fading leaves should be removed and the plant should be repotted to refresh the soil if the mix is over 3 months old. You may certainly repot less often but you'll see a big difference in the health and blooming of your plants if you tend to them regularly.

Yarn wick?

Do you feed the plant? If so, what and how much?

Yes, I use an acrylic yarn which I unravel for minis and babies, but use thicker on larger plants. I happen to use a soil mix that has fertilizer already in it, but when I do not, I use a liquid feed made by Dyna-grow. If you hand water the general rule is to feed weakly, weekly. Just like with orchids. The actual amount to use varies depending on what you use but an average is 1/8th of a tsp to a gallon, up to 1/4 of a tsp per gallon if granular. A little more if it's a liquid.

My flats contain a bit over a gallon of clean water each, no fertilizer unless I haven't been able to repot in a while. I clean out all wicking reservoirs once a month to keep them clean. Flats and grids I bleach and rinse in my bathtub. If you use deli-containers or glass jars, I'd do it at least twice a month as they are clear and will grow algae. Or use Physan or similar product to discourage algae growth. I don't need it in my flats because they are black and I don't get algae if I clean them monthly.

You may do internet searches on 'wicking African violets' for more information. I wouldn't suggest you wick while you have your plant bagged or domed. Wait until it comes out and adapts to your regular air. If you prefer to hand water, that's fine too! I have thousands of plants in my art studio so hand watering isn't feasible. ;)

I'm going to reiterate because I really want this plant saved.

Repot into much smaller container.

Add perlite.

Repot broken stem into own bagged tiny pot.

Do. Not. Fertilize. Until bagging is done.

Im hand watering, so add liquid fertilizer to gallon of water, and water after bagging. Store gallon out of sun.

Yes?