Greetings, caretaker. We are the vibrant Impatiens, often called Busy Lizzies or Touch-Me-Nots, and we bring brilliant color to your shady spaces. However, we are susceptible to several ailments that can diminish our beauty and health. Understanding these diseases from our perspective is the first step toward effective treatment and a thriving garden.
This is our greatest fear. It begins subtly, with a light green stippling or yellowing on our upper leaves. You might not notice the real culprit: a delicate, white-to-grayish fuzz on our leaf undersides. This fuzzy growth is the pathogen itself, reproducing and spreading. As the infection progresses, our leaves curl downward and drop prematurely, leaving us weak, stunted, and bare. It spreads rapidly by wind and water, especially in cool, wet, humid conditions.
**Our Plea for Treatment:** Please act at the first sign! Remove and destroy any of our fallen or infected leaves immediately. Improve air circulation around us by spacing us properly and avoiding overhead watering. For severe cases, we may need protectant fungicides containing fosetyl-Al or specific fungicides like mancozeb. Please note, once the infection is widespread, it is often best to remove us entirely to protect our healthy neighbors.
Unlike its downy cousin, this disease presents as a distinct white, powdery coating on our upper leaf surfaces, stems, and flowers. It thrives in humid conditions with crowded air flow, but unlike downy mildew, it prefers warmer days and cool nights. This powder saps our strength, causing our leaves to yellow, distort, and potentially drop, weakening our overall vigor.
**Our Plea for Treatment:** Help us by thinning our stems to improve air movement. Apply a preventative spray of horticultural oil or neem oil, which creates a protective barrier. For existing infections, a baking soda solution (1 tablespoon per gallon of water with a dash of horticultural oil to help it stick) can be effective. In persistent cases, sulfur-based or other labeled fungicides can be used.
This is a below-ground assault, often caused by waterlogged soil from overwatering or poor drainage. Fungi like Pythium and Rhizoctonia attack our root systems, making them brown, mushy, and unable to absorb water or nutrients. Above ground, you will see us wilt dramatically, even when the soil is wet. Our stems may become soft and dark at the base, and our overall growth will be severely stunted.
**Our Plea for Treatment:** Prevention is paramount! Please plant us in well-draining soil and ensure our pots have drainage holes. Water us deeply but only when our topsoil feels dry to the touch. If you catch it early, you might save us by carefully removing the soggy soil, trimming away any blackened, rotten roots, and repotting us in fresh, sterile potting mix.
Bacterial diseases, caused by pathogens like Pseudomonas syringae, manifest as small, water-soaked spots on our leaves. These spots often enlarge, turn brown or black, and may have a yellow halo. In the case of bacterial wilt, the bacteria clog our vascular systems, causing a rapid and fatal wilting. These diseases love moisture and enter through wounds or natural openings, especially in splashing water.
**Our Plea for Treatment:** Water us at the base to keep our foliage dry. Remove and destroy any spotted leaves immediately to reduce the bacterial population. There are no effective chemical cures for bacterial diseases once they have taken hold. Copper-based bactericides can offer some preventative protection but are not a reliable cure. Your best strategy is strict sanitation and avoiding working with us when our leaves are wet.
