You purchased a flat of gorgeous, carefree impatiens for your early spring garden in hopes of bushy, colorful blooms throughout the spring and early summer. However, your dreams are dashed when you start your watering rounds one morning and realize your impatiens have stopped blooming. Don't despair or throw out those temperamental beauties just yet. Impatiens, fortunately, are America's premier annual bedding plant due to their ability to continuously bloom with little care. Chances are that a quick care adjustment will set those pretty plants back to rights in no time.
Provide adequate shade for impatiens plants. Some new hybrids are being sold as full-sun compatible, but for most impatiens species part to full shade will provide best blooming results. In direct, harsh sunlight, your impatiens will likely reduce or cease blooming, and possibly drop flowers and leaves altogether. Try moving your sparsely flowered plant to a more protected location.
Avoid over watering, which causes stress and ultimately decreases blooms. Severely water-logged soil may provide ideal conditions for root rot or other water-friendly diseases. One cue that the plant is taking in too much moisture is a red tinge to the foliage. Alternately, check to ensure that soil is moist and never allowed to completely dry out. Lack of water may also cause bloom reduction.
Fertilize every two weeks to provide food for blooms. Without regular fertilization, annual plants like impatiens will likely produce a smaller bloom count than desired. Balanced liquid or slow-release fertilizers are both good options. Take care to follow manufacturer recommendations. Over fertilization may burn or damage a plant.
Check the plant for disease or insect infestations. Bugs, such as aphids and thrips, or fungal disease may attack any annual species. A steady spray of water to the foliage may loosen the bugs and larvae from the pant. Occasionally, a fungicide may be advisable for serious fungal outbreak, but follow manufacturer instructions carefully and use on annuals as a last resort.
Prune to encourage new growth if blooms remain elusive. Although impatiens are popular specifically for their ability to bloom and re-bloom without deadheading old flowers, cutting a bushy plant back may encourage a flush of new blooms in subsequent weeks. Pruning dead or diseased foliage also will encourage healthy growth and blooms. Just be sure to sterilize tools in a solution of equal parts bleach and water to avoid spreading contamination.
Ask local garden experts, at garden centers or university extension offices, for regional and cultivar specific information. Climate, blights or infestations, and local weather trends may be the cause of bloom cessation. Experts who live in your area may provide specific suggestions based on what other gardeners in your area are experiencing with similar plants or problems.