yeah... posting a picture is best. Brown edges on the lemon balm make me think of over watering. Sometimes overhead watering in a humid environment can cause fungus to grow... so a pic is best if you can.

Sheri, I could have written your post. Except my mint with the brown spots is my orange mint (just got spearmint tonight) and my lemon balm also has the brown edges.

My only question is that DH suggested I put seven on it because he uses it on cabbage (at least I think that's what he uses)and thought it would work on the mint also. Any advice on that? I'm a bit leary.

Carrie

Seven is a very 'serious' chemical and is not recommended on the leaves of herbal plants. If your concerned with fungal infections, there are safer products. Also neem oil would be a safe choice for insect prevention. For cabbage and its other family members, the cabbage looper (green caterpiller and white moth) has a field day with the greens and using somthing like a Bt insecticide would be a better choice. Spraying harsh insecticides and chemicals on edible leaves tend to concern me, and I don't know if your into organic gardening or not, but you must realize that what you spray may also be what you eat later.

The only disease likely to affect mint in the UK is rust. Do you have that in the States?

Rust is a possibilty. A good clean area for growing mint is advised, and laying down a light layer of peat moss will reduce fungal growth as will minimal watering early in the day, with plenty of sun. Garden sulfur spray will help control rust.

Still no picture (sorry) but the mint is hanging on, not getting worse. I think it may be overwatering or poor drainage. It is in a wine crate, which I lined with a black trash bag, then put in a layer of styrofoam peanuts, then put in the soil. I drilled three holes in the bottom of the wine crate and poked holes in the plastic bag in the same places. Maybe I did not use enough styrofoam? Maybe not enough drainage holes? I am thinking of drilling some more. When I go to water, this box feels more moist than the others, so I am watering it less now.

Any chemicals at all are out for me, as my daughter plays in this area, grabs the herbs, etc.

BTW, I am a total newbie to all this. All of the above (the plastic bag, the styrofoam) was recommended to me by a gardener I met. I also planted a mix of herbs in this box without regard to their varying water needs (which someone pointed out to me on another thread). I will just see how they do for the season.

Thanks,
Sheri

Sheri, it likely is rust, a fungal disease. But with mint a simple solution is to cut out the affected stems before it spreads. Regrowth is usually not affected if you remove the damaged shoots early.

I wouldn't hesitate to use the affected leaves for teas, however they are not marketable or suitable as garnish.