yellow cannas? PLMK

Yuccas are not good low light plants, although some retailers will try to sell them as such. Ten feet from a window is low light and that is the primary problem. Inadequate light causes a plant to slowly starve so symptoms often take a long time to appear. The plant gradually sacrifices older leaves so it can continue to support new growth. Better light is the only answer for you and it will take quite some time for it to stop shedding older leaves and gradually recover. Will Creed mrmothernature@gmail.com

The potting mix is just a standard potting box just bought at walmart. Nothing special. I used to water it once every 2 weeks and fetilize about 1 per month in the summer and once in the winter. It was placed by a window before it got sick but now I moved it to try to recover it. It almost looks like it has some sort of fungus. I just don't know which one. How do I recover it from it?

I'm with gardengal. The watering method I explained won't work without drainage, so I'd get the plant into something with a drainage hole ASAP, even if it means keeping it in a sub-par soil. The best soil would be a 5:1:1 mix (5 parts composted bark fines (between dust and 3/8"), 1 part peat, and 1 part perlite. If you can't find good bark fines, the next best solution is to pick up a bag of fairly chunky cactus mix and use 50% of the mix to 50% perlite (preferably the coarse kind without much dust. You need to get all the old soil out of the roots if this is going to work. The easiest way usually to start when the soil is fairly dry, shake off whatever your can, and dunk the roots in a pail or other large container of water, swish it around, and use your fingers, a chopstick, or whatever you have on hand to untangle the roots enough that the soil comes out, kneading it a little as needed. Cut any rotten roots back to healthy tissue, do your best to preserve any fine roots, and use a spray bottle to keep them from drying out while you're working. My guess is that you won't find a whole lot of fine roots, in which case most of the soil will fall out on its own. If you find a bunch of thick woody roots circling the pot that don't have fine roots attached to them you can cut them off with sterilized scissors or shears, but at this point that's less important than getting the plant in a good soil so it can recover. When you replant, fill the pot about 2/3 full (depending on the size of the root mass), spread the roots out on the mix, then add more mix a bit at a time, using your chopstick or whatever works to fill all voids in the roots with the new mix. I find it helps to whack the side and bottom of the pot every little while to help things settle in place. Stick the roots in a bucket of water or cover them with damp soil if you need to stop the process at any point.. When you're all done water well, making sure to cover the whole surface of the mix. Put the plant somewhere it will get indirect light and don't fertilize until you see new growth, at which point you can move it in front of a window they gets direct sun. The leaves should stop yellowing almost immediately, but it may be a while before you see a lot of improvement because the compromised root system needs to regrow before it can support new vegetation. Do post pictures of your progress, and don't hesitate to ask for help if you get stuck. Good luck--I'm looking forward to hearing how it goes and how your little green friend does!