If a plant is under stress, it should be fed
Fertilizing plants that are not nutrient deficient can lead to additional stress. Fertilizer is added to plants growing in poor soils and to plants that show symptoms of lacking a particular nutrient. Generally, when a plant is stressed, it's not from lack of food. Compacted soil, heat, salt spray, faulty planting, and improper placement are usually the culprits that stress plants. It is important to rule out other environmental conditions before deciding a plant is underfertilized. When fed, stressed plants use up energy that is better spent on growing roots, walling off decay organisms, or defending against insects.