View Full Version : Mint leaves are yellow with brown spots

04-20-2015, 05:57 PM
Hello this is my first post. A few months ago I purchased a small Spearmint plant. It's grown very quickly and became very bushy. Now it seems to be getting thin and some of the leaves are turning yellow and with brown spots. Is it because those leaves were not getting enough sun? Could it be something else? I haven't trimmed it at all because I wanted to let it get as large as possible before using the leaves next month. Should the yellow leaves be pulled off? When I want to use the leaves is it better to clip them off or just pull them off? Should I clip a few leaves from each stem or clip off a stem? If I clip a few leaves from a stem will that stem continue to produce more leaves? Going forward are there any suggestions or guidelines managing the plant or clipping it? Will healthy leaves stay green and remain for the life of the plant or do the leaves have a lifespan and at some point die and fall off? Thank you for any helpful information.

04-29-2015, 05:23 AM
Hello Strandman,
Although I have not dealt with mint plants specifically, I've seen that same phenomenon with my Oregano plant that has sort of overgrown its pot. I did go ahead and remove the yellow and brown spotted leaves from my plant. In general, I would say if you try to pull the leaf and it wants to come on its own, go ahead and remove it. If you've got much force, and it's not diseased, I would let it be for now.

For my oregano plant, I believe that it was not getting enough water to really water the entire plant, mostly stemming from the size of the plant as it has grown and the ability of the pot to water a plant that size as frequently as I am able to water. Because of this, I went ahead and cut back some of the entire stems of the plant for drying even though I know I should generally be waiting until the flavor has peaked just before the plant flowers. I am hoping that this cutting will help the plant to stay within the budget of time and watering that I can give it.

Mint is similar to oregano in that if you are planning to dry your mint leaves, the best flavor is saved by cutting the stalks just above the first set of leaves as soon as the flower buds appear. However, you can harvest the leaves and enjoy them fresh anytime. In general, I cut - not pick - my fresh herbs to avoid damaging the plant by accident, by I understand the convenience of picking. If you're taking a couple leaves here and there, I wouldn't worry too terribly. If you're harvesting a bunch of leaves for use fresh or making a cutting to dry your herbs, go ahead and bring out the shears.

Overall, I would pick out the troublesome leaves - likely they will fall off easily - and then make some cuttings of entire stems as noted above. If the health of the plant improves overall, just from these steps, great, if not I would do a little more digging!

Happy gardening,

05-12-2015, 04:45 PM
Thank you very much for the helpful reply. I didn't get any notification so I didn't realize that someone actually replied. I removed the leaves with some cool little snips that I bought. Then for the Derby I cut many leaves from both plants. I'm starting to see new growth but now I'm also noticing some black flecks sitting on some of the leaves. I'm not sure what they are or why. I've noticed a few little bugs of different variety and some kind of little furry caterpillar or worm. It looks like something is eating some of the leaves. I'm concerned about the black flecks sitting on the surface of the leaves and I need to research that now. Thank you again for the reply.