Hi. I would like to see if I can get help to assist in identifying yellow mottling on the leaves of several of my plants. I live in zone 5b (GTA – Brampton, ON). This is in my back garden facing NW. New soil added (6″) in spring to garden beds consisting of live organic soil from Gro4 Organics, Organic Worm castings from Home Hardware added and Mulskie fish emulsion fed 3 x to plants this season. Containers all had a bit of the growers mix along with worm castings and pro-mix organic herb & veg. Mottling first came apparent on elderberry trees. On the European it looked more yellow or pale green mottling but on the American it looks more like yellow spots that eventually go brown. I then discovered it on a AK auto cannabis plant a few days ago and then on my Valerian plant yesterday. All plants are in sun from noon to 7 pm. with a bit of dappling sun afterwards. I originally thought it was from the heat but I posted on gardening forums and was told this could be the mosaic virus or yellow spot fungus and would like to see if anyone can assist me. I have been to local nurseries who could not identify. I have quite a few pictures of the different plants but the site will only let me upload one. The picture is of the European Elderberry (Sambcus Nigra – Korsor). The other European Elderberry trees and the American Elderberry trees have similar yet different patterning that almost always goes brown around the pattern. The cannabis plant is dimilar yet different too and the pattern is much more circular.
If you need picture of those to compare, I would be more than happy to send through as well. Thank-you in advance, Cindy.
Oh dear! This is awful indeed that so many of your plants are affected by this mottling. I have to concur that when we hear of different varieties being affected by the same affliction what immediately comes to mind is Mosaic virus. This virus is spread by aphids, and typically effects tomatoes, cucumbers, eggplant etc. but can quickly spread to other plants. I am attaching a link detailing this problem, I suggest you examine the photos and compare with your plants to confirm this suspicion.
There are other explanations for this occurrence, and one this may also account for so many of your plants being affected is chlorosis. This is caused by a soil deficiency, by your account you have amended your soil very well, but it could be that by all of your additions you have put the ph level of the soil out of balance. A soil test will be required to check this. Here is a link that describes Chlorosis
Another aspect of all of your soil amendments is that you may have overdone it! Your plants may be suffering from fertilizer burn. This can especially occur when fertilizer is given during times of drought – and that is something that we can all relate to in the GTA. I have been holding off fertilizing my garden for a month now – I am waiting for a few rainy days in a row before I go ahead. Here is another link for you on this issue. I hope I have not given you too much reading material. Good luck with your garden.