While we have started to see some warmer temperatures and sunny skies in Lincolnton, this spring has had a lot of particularly wet and cool weather. This weather or environment may contribute to a significant number of plant issues as we head into the growing season. When experiencing plant issues, there are a few things to keep in mind.
There are two different causes of most plant issues- abiotic stressors and biotic stressors. Abiotic stressors are environmental issues—things like floods, drought, extreme temperatures, soil fertility, and so on. Abiotic stress can cause a decline in plant growth, development, yield, and seed quality of crops and ornamental plants. Most abiotic stress factors can be managed by the homeowner or farmer, such as selecting the best site for your desired species, applying irrigation during times of drought, and evaluating soil pH and fertility on an annual basis.
The second cause of plant issues are biotic stressors. Biotic stressors are living organisms, specifically viruses, bacteria, fungi, nematodes, insects, and weeds. These pathogens cause various types of diseases, infections, and damage to crops and other plants which can cause a decline in plant growth, productivity, and death. In order to have a biotic plant issue, we need three things- the pathogen or causation agent, the host-plant, and an appropriate environment for the pathogen to develop and thrive. Managing biotic stressors relies on our ability to identify which of those three things we have involved and modify them in some way. Sometimes, we are able to plant varieties that are genetically resistant to disease or infection by a biotic stressor. Other times, we might need to remove the affected plants, manage an abiotic stressor that’s contributing to the issues we see, or use a chemical control method. Even then, we might choose not to even treat an affected plant—especially if it’s something that will resolve itself with enough time.
Figuring out if we have an abiotic or a biotic stressor can be challenging, and often it is a combination of both. If there is only abiotic stress, we generally will see an entire region or planting all exhibiting the same signs and symptoms. For example, an entire raised bed of vegetables that won’t grow is probably going to be an issue with soil fertility or watering- environmental issues. If we have a biological agent such as an insect or disease, we typically see very specific patterns of disease. For example, a single area of a crop field that fails to grow well might be a root-knot nematode. Every other plant outside of the affected area might do just fine, but that affected region will not. It gets a bit more complicated than that because abiotic, or environmental stressors, can often damage or stress plants and make them more susceptible to biotic stressors like disease.
The wet, cool weather we’ve been seeing as we come into spring is going to cause an increase in some plant issues, both abiotic and biotic in nature. If you are interested in having our agriculture agent visit your property to help diagnose the issue and make recommendations for handling it, please let us know at uge3181@uga.edu or 706-359-3233.
