This looks like spider mite damage. Look for the fine webbing and small spider like mites on the under sides of the leaves. The mites themselves are very difficult to see with the human eye, so hold a piece of paper below the leaf and tap or shake slightly to see if anything falls off, or, take a spray bottle of water and spray it in the leaf axils. While the mites are very difficult to see, their webs catch the water and becomes more easily visible. You may wish to show your photo to a local garden center for confirmation of the problem, so they can help you select the right control.
Are you growing under artificial light? Spider mites thrive in hot dry conditions and plants growing under artificial lights are often especially hot and dry. (The distorted light in your photograph is typical of fluorescent lighting, which is why we ask.) Spider mites spread quickly, so check any other plants growing in this area for signs of a problem.
Leave A Comment