Just stick it in a glass of (room temp.) water so that the bottom 2-4" of the stem are in the water. I don't change the water, I only ADD to it, but I also throw in some bits of charcoal chips (aquarium grade from the pet store) which keeps the water from getting yucky or growing algae. Will take quite some time so pls. be patient, if you've got a clear vase than you can SEE when it roots, otherwise, just take the stem out to check in a couple of months & then every month or so.

If this were my plant, this is what I would do. First I would look under one of those leaves for something that looks like very small particles of white sand within the pockets between the veins. The stipling on the leaf looks like something is feeding on it, possibly spider mites. You might not see any webbing but for that, look at the leaf nodes at the stem. The spots look like leaf spot to me. Though it is a little hard to tell from the photo, it seems some spots are developing lighter coloring within the spot. I won't guess what type of leaf spot it is, but below is one source that lists types of leaf spot that might affect mint. Here are two pictures of phosphorus deficiency that look similar to your damage. They are shown by other plants types and compared to most pics representing phosphorus deficiency, yours really doesn't match. Are these pics incorrect? Who knows but it is interesting that the clover site mentions it is caused by cold roots that cannot uptake the phosphorus and wasn't your plant stationed at the window? http://www.windowbox.com/tomatoes/tomatosolutioncenter.html http://www.luminet.net/~wenonah/min-def/clover.htm As Ken writes, the temps drop next to the window especially at night - radiant heat loss and such- many of my plants can't take that position. The leaves crisp and drop in my house. The roots will rot. My plants do a little better if they are a foot or so away. They do even better under lights in the basement. Plants reaching for light do seem to loose the bottom leaves, don't they? If it were my plant, I would cut off anything that looks damaged. I would throw out the soil and change the pot. I would prefer a clay pot that breaths to a plastic pot. Though they dry out faster, they don't promote fungal rot as much. You don't have the same damp water lingering in one place as long, growing mold and fungi. I would examine the size of the root and choose my pot accordingly. If it ends up being spidermites or such, I would cut the tops off all together, rinse the white roots - they should be white in mint - and spread them out in a new pot. They will grow. I do this every year when I refresh my pots of mint. I leave them outdoors in pots all winter. Most of it dies but a few bits of root live and are obvious by being white. I take these bits, lay them out, throw out the old withered, pieces and the mints refresh themselves. Finally, if you still have problems keeping them indoors, divide the root, create a new pot and bury one outside where it won't sit in water and ice over. In the end, as long as you can somehow keep them going for the winter, it will refresh come spring when you can bring it outdoor and trim the roots if needed and the top. Here is a link that might be useful: APS - Diseases of Mint

Thanks for the help. The photo is from my phone camera, so it is not the best. But you can clearly see the lighter, brighter green new leaves (third rhizome from the right) which unfurled from their sheath just in the past 48 hours!!! No kidding. Before that, it looked like the "sheathed" growth of an unopened rubber-tree plant leaf. This is in addition to the other new shoots that have appeared since I got the plant on May 11. This rapid growth ASTONISHED me, as on-line research kept referring to ZZ plants as "very slow growers." (I am joking with my friends that my ZZ plant somehow aspires to be an oak tree, or that atheletes must be sneaking into my home when I am at work and dumping performance enhancing drugs into its pot. LOL.) I watered it on the 18th and watered it again last night, June 1, and am sticking with watering every 2 weeks Should I water more often? The current pot is about 10 inches across. Last night I purchased one that is about twice that size (the largest one I could find with drainage holes) and will re-pot the plant tonight.

Sunlight coming in from an east or west direction comes in at an angle and isn't as intense as sunlight bearing down on us from directly overhead during the afternoon hours. Your ZZ plant will love it. Now that the Fall Equinox has passed, and the Sun is moving further south for the winter, the sunlight comes in at an angle all day long. It's more dispersed and less intense. So I've moved my ZZ plant further out into the open to soak up more sunlight throughout the day. It is getting direct sunlight all day long now, but I keep a close watch on it. I wouldn't even think of doing this during the summer. It would most definitely get sunburned. But as I said, the Sun is moving into the Southern Hemisphere for the winter, and the sunlight that reaches us is more spread out and weaker. Since your plant is still young, I wouldn't recommend trying this. I only mention it to point out the fact that just because plants tolerate low light levels, it doesn't mean that they prefer it that way. I keep all of my plants on the brighter end of the spectrum, giving them as much sunlight as they can tolerate, not less. That sunny eastern window will make a great home for your ZZ plant.