Try and distinguish between the new growth and the oldest leaves, especially on artichokes. As long as the rhizomes stay healthy, the leaves & fruit will eventually come, no matter how ratty any one leaf looks. Transplant shock can be rough and produce stress signs in all plants, but it's best to wait it out a bit and see if the new growth recovers. Splashing soil up on the leaves while watering can produce yellow & black spotting too, it's one of my biggest challenges, as a moment of garden ADHD while watering means I've just splattered an entire row of seedlings with soilborne fungi and bacteria. It's often localized and never spreads beyond the affected leaf, except on my solanums (tomato, eggplant, potatoes, ...) it can mean I've just sent early blight everywhere, as I can't seem to get that disease out of my garden ever since my Home Depot tomatoes were infested. Whiteflies leaving your nursery-bought plants is a huge problem, it's illegal for the nursery to sell you infested plants. Get a refund and/or find another nursery. I rarely use box stores anymore, their pest prevention is weak (at best).

I'm curious as to what kind of zinnias you're growing. Some are much, much more susceptible to typical diseases than others. On the other hand, there are others that seem darned near invincible! One of the best methods of preventing disease occurrence is to select those resistant varieties in the future. Corn meal has been proved to be a very good weapon in our battle against certain fungal disorders. Incorporate it into the soil when planting your zinnia (or before sowing). You can also soak it in warm water to make a corn meal 'tea' to be used as a spray. Corn meal is not effective against powdery mildew, to my knowledge, but the assortment of diseases that fall under the term: 'black spot'. If you haven't tried the "Profusion" series of zinnia yet, you should treat yourself next season. I've never seen fungal diseases of any kind over the several years I've grown these plants. They bloom early and continue on and on until frost. "Magellan" zinnias have been PM free for me but developed black spot the first year. I've used corn meal ever since with success. I'm sure that there are other resistant hybrids and cultivars...hopefully folks will suggest their favorites.

I'm not finding photos of necrotic blight, but other blights show darker spots with a circular pattern not seen on my leaves. Also my fruit is unaffected. Septoria Leaf Spot sounds and looks similar to what mine have. Either way, the treatment is removal of affected leaves and a copper spray. I will do both as well as a preventative spray on my other tomatoes. Thanks, Omni.

Hello whathousework, Gardengal is correct, what your zinnias have is not an insect problem. She mentioned Bacterial Leaf Spot, and if that is correct, nothing that you can spray will get rid of the bacteria. Yellow halos around the dark spots is a symptom of bacterial infection, and that would indicate incurable Bacterial Leaf Spot. However, sometimes Alternaria Leaf Spot will have a little yellow border and there is a possibility that your problem could be Alternaria Leaf Spot, which is a fungal disease that can be controlled with good fungicide sprays. The BioAdvanced brand that you mentioned is a good one, and they make a BioAdvanced Disease Control for Roses, Flowers & Shrubs that could be effective against Alternaria Leaf Spot of zinnias. It is systemic, which means it is absorbed into the plant and becomes a part of it, so that new growth is protected. Not forever, but for more than a week. Non-systemic sprays can get washed off the next day, or possibly even the same day you spray them. ZM (not associated with any product or vendor mentioned or linked)