Why are the leaves on my potted herbs yellowing
Hi, My boyfriend and I have recently started a little hanging herb garden in our courtyard, but we have been faced with a number of problems! The herbs are planted in recycled soft drink bottles, in a hanging shoe storage bag. We've had a lot of trouble with Thrips in the herbs and also Violas, and are using a Yates spray for these (but with Melbourne's random rain it just gets washed off) But the other concern we have is a lot of yellowing on the leaves. This began happening on our Chocolate Mint, but also Lemon Verbena and Greek Basil. The leaves on the Basil are around the bottom, but the Mint and Verbena the discolouration is more random, and also kind of dark and speckled too. They seem 'brittle' and fall off easily when touched. I don't think they are being over watered, as I know Mint likes a lot of water, and they often get to dry out before being re-watered. I am suspecting that this might be that they are over growing their pot? Or would you suggest lacking in a mineral? Or is a dew or mould or similar causing the yellowish speckled look like in the picture of mint leaves? Thank you so much!
Growing plants which are normally in the ground in the air can cause a lot of problems. Pots, especially hanging pots are prone to getting hot and drying out, this puts the plants under stress making them more susceptible to fungal and viral infection. Your plants are also likely outgrowing their containers meaning they are suffering nutrient deficiency which would be causing the leaves to discolour, try regularly applying Yates Thrive Vegie & Herb Liquid Plant Food and repotting your herbs. Try not to let the potting mix dry completely leaving it moist but not wet is fine for herbs. Keep applying the spray to control the insects, once the plants start to recover the insects will be less interested in those plant.
Answered: 9 Mar, 2015