Lemon Verbena

Hi Carol,

The leaves turning black or brown around the edges indicates that the plant is stressed. Pots tend to dry out quickly and I think perhaps it is getting too much heat being right next to a slider, it may be getting a bit scorched and be very thirsty.

My recommendations would be to move the pot from the position it is in, It does best in a sunny location but being near a window or a slider may be too much direct light and too warm. Increase the watering but ensure the pot has good drainage and that it is not sitting in a saucer of water.

If all else fails, re-plant in the garden outside.

Good Luck, lemon Verbeena is an amazing plant.