Hello. I am getting worried about my mint. I bought it at Hope Depot a month ago. I kept it in this pot size on a sunny yard for about two weeks. I then brought it home and set it by the window. Most of the leaves look fine, and I've trimmed it quite a bit by now, but I am noticing black and yellow discoloration of some leaves, and eventually falling off. It's not a huge issue right now but I'm worried it could get worse.

Since the plant is indoors, I am not expecting to have too many bugs. What else could it be? I used a special herb/vegetable soil with nutrients so the soil should be fine.

Mint is a gypsy, needs to spread its runners out and travel to grow, but does best in Spring- dying back about July here, In house could be lack of humidity (In home humidity with a/c is usually about 40%)lack of light, lack of root depth. Could be too much water retention in the bottom of the pot as well.

Since I bought it a month ago, am I just too late in the game? I thought that mint is a perennial, ie I can keep it all year around, especially indoors?

You should be able to do so, but plants like mint thrive on different conditions than in house plants. This peppermint has grown AWAY from my July sun


Kentucky Colonel Spearmint hasn't that option, but was thick and lush til mid June and upper 90's temps.


Mojito Mint travelling 4' from original spot, again away from sun. I flood them with water since there is good drainage here- it is dry the next morning.


Last, in ground peppermint started this Spring from snippings, gets even more neglect, dry leaves (brown, curled) I see as dry roots.


Yellow leaves are dying leaves, can be caused by overwatering, underwatering- or even just stem grown too long and not pinched.

Thank you. I've seen people prune mint all the way to the ground to revitalize them. I'm scared to do that! Can I prune it all the way down to an inch off the ground? Will it grow new offshoots without any leaves remaining?

Usually pruning down to 3rd joint from bottom is sufficient. Pinch IN the middle of the stem above the 3rd joint. I have so much I simply rip them out and stick in the ground. They have grown up thru my dirt from 1' down when I pour new soil on top of them. Think of it as a stinky weed you are going to deadhead, that will make it want to survive.

@truszko1 have two outdoor pots of spearmint and two of peppermint, I just harvested a bunch of still healthy peppermint for drying, but the spearment is now flowering--I'm leaving it for the bees-- and the leaves are yellowish and unattractive. I'll cut them back when the flowers fade. I refurbished all the pots early this spring and cut off all the top growth. The mints have running roots, and you'll get top growth anywhere you leave them in the soil. I also leave these pots out during freezing weather in the winter and they do fine with some mulch over them for insulation. Our temps probably don't get as low as yours, but we do get hard freezes and some snow. I'm wondering why don't you keep the pots outside for the summer? They do like sun. (Part sun, here in the high desert.)

@kittriana, I'm curious, why do you say MIDDLE of the stem?

I don't have a yard myself. I kept it at my parents yard at the beginning, and then I moved them to my apartment.

Of course . Try to give it as much exposure to daylight as possible.

middle of the stem keeps you from pinching off the new growth in the v of the joint that you can't see. Mint indoors without heat can lose its aroma, east sun, south sun is preferable, no balcony? Some mints are native to Wis and Ill, but it would need some root protection in Chi towns' icy winters.
3rd joint is recommended not lower- keeps it healthy since you have it in curtailed circumstances.

Posting an update... I decided to cut down the mint all the way to the ground last month. Look at how it's come back! Incredible! =) still only indoors.

It's always so gratifying to hear success stories! Thanks for letting us know.