Solutions: Some steps to take to address black spot include: Prune away any infected leaves, cleaning the pruners between plants with a 10% bleach solution so that the fungus does not spread to healthy leaves. Don't compost pruned plant parts as the spores can linger in the soil for a long period of time - instead, dispose of them in the trash. Use an approved fungicide such as Trifloxystrobin, Chlorothalonil, Maneb, or Myclobutanil. Use a spreader in the fungicide spray to ensure better coverage.

Solutions: The easiest (and most obvious) way to address underwatering is to fully hydrate the plant. However, this must be done carefully. A common mistake that many gardeners make is to douse their underwatered plants with water. This can overwhelm the roots of the plant and shock its system, something that can be even more damaging than the lack of water to begin with. Instead, water thoroughly and slowly, taking breaks to let the water slowly saturate through the soil to get to the roots. Use room temperature water, as cold water might be too much of a shock. In the future, shorten the time between waterings. A good rule of thumb is to check the soil around each plant daily. If it’s dry to at least two inches down, it’s time to water. If a container plant is repeatedly drying out very quickly, repotting into a slower-draining container might be a good idea, too.

Solutions: As powdery Mildew spores are transported by the wind, it can be tricky to put a complete stop to the spread of the fungus. Luckily, there are several easy treatments for plants that are exhibiting symptoms: If powdery Mildew seems to be impacting isolated leaves or stems, they can simply be trimmed away and disposed of. Disinfect pruning tools after doing this. Remove any plant debris from the ground around the infected plants and dispose of it in the garbage. Then, cover the soil with a thick layer of mulch to limit reinfection. Milk sprays have been found to be useful in controlling powdery Mildew. Make up a spray consisting of 60% water and 40% milk and spray on the affected plants. This can also be used as a preventative measure. In cases where powdery Mildew is more widespread, plants can be sprayed with a mild sulfur- or copper-based fungicide or a non-toxic solution made from baking soda and soap. Sprays can help areas that have been recently infected, though they are less effective against well-established infections. If possible, try transplanting the plants to a sunnier location. Though powdery Mildew does fine in hot, dry conditions, it is unable to reproduce without some humidity. Putting plants in more direct sunlight can help stop the spread of the fungus. Trimming around closely-packed plants can help improve airflow, which also prevents the reproduction of the fungus.