I bought a peppermint plant from a supermarket last Monday and it's now wilting noticeably. I've been watering its soil daily because we're going through a warm spell and the soil's dry (it's about 24 degrees today, 75 Fahrenheit). The stems are all very soft and floppy, though they aren't discoloured except for a few browning leaves, and the leaves still taste fine. It isn't in direct sunlight; it's by the north-facing window, but sitting behind the blind rather than in the light part. If it'd help, I can move it. Any ideas as to what I can do to perk it up a bit? The only things I can't do are give it plant food or repot it, because I haven't got access to food or new soil.