Impatiens bring vibrant color to gardens, often thriving in shaded areas where other flowering plants struggle. Confusion about their light needs stems from the significant differences between the two primary types: the traditional variety and the New Guinea hybrid. Understanding which type you have is the most important factor in determining the correct planting location for maximum health and blooming.
Differentiating Impatiens Light Requirements
The most common variety, _Impatiens walleriana_, often called Busy Lizzie, is a shade-loving plant that thrives in deep or partial shade. Traditional impatiens must be protected from direct, intense afternoon sun, which quickly scorches their delicate leaves and causes severe wilting. They require bright, filtered light or gentle morning sun to produce abundant flowers.
The second major type is the New Guinea Impatiens (_Impatiens hawkeri_), which is significantly more sun-tolerant. These plants perform well in partial sun, requiring about three to six hours of indirect or dappled sunlight daily, and do best with morning sun and afternoon shade. Their broader foliage is less prone to burning than the traditional variety. However, even New Guinea types struggle to stay hydrated in full, all-day sun, especially in hot climates. Newer hybrid varieties, like SunPatiens, are bred to tolerate full sun but still require consistent moisture to manage heat stress.
Recognizing and Correcting Light Stress Symptoms
Plants signal when they are receiving the wrong amount of light, allowing for timely correction. Too much sun causes leaves to develop a bleached, yellow, or bronze appearance, often with brown, crispy edges (sun-scald). The plant may also wilt dramatically, even after watering, because the rate of water loss is too high. Immediate action involves moving container plants to a shadier spot or providing shade cloth for garden beds.
Conversely, symptoms of insufficient light relate to poor growth structure and a lack of flowering. Impatiens in deep shade become “leggy,” meaning the stems stretch out and become thin. This elongated growth results in a sparse, weak appearance and significantly reduces or stops blooming altogether. To correct this, move the plants to a location that provides brighter, indirect light, such as a spot receiving morning sun. Pruning the stretched stems encourages bushier, more compact growth once the light environment improves.
Watering and Soil Requirements for Impatiens
Impatiens are naturally moisture-loving plants, and their watering needs are directly linked to the amount of sunlight they receive. All species require consistently moist, but not soggy, soil, as they are not drought-tolerant and will quickly wilt, dropping leaves and flower buds when stressed. Plants in containers, especially those in brighter light like New Guinea varieties, will typically require daily watering, while those in shaded garden beds can often manage with less frequent applications.
The soil composition must balance moisture retention with excellent drainage, achieved by amending the planting area with organic matter like compost or peat moss. This well-draining environment prevents the dense, heavy soil conditions that lead to root rot, especially in deep shade where evaporation is slow. Because impatiens bloom continuously, they are heavy feeders and benefit from consistent, light fertilization throughout the growing season. Applying a balanced, water-soluble fertilizer every four to six weeks supports prolific flower production.