Answer: Impatiens will often wilt and stop blooming in the heat of the summer, especially if they are in too much sun. Keep watering and they will begin to bloom again when the weather cools.
Since your impatiens are under stress, you might want to watch out for diseases, too. Fungal diseases sometimes attack impatiens. A wilt disease works its way up from the base of the plant, causing leaves and branches to wilt and die. A leaf spot disease causes circular brown spots on the leaves. Stem rots attack impatiens stems at or near the soil level. Foliage turns yellow, wilts, and dies.
There is no practical treatment for these problems in inexpensive annual plants which die at the end of the season anyway. The best strategy is to promptly remove and discard badly infected plants with their soil in the trash to prevent the spread of the fungus to other plants.
Good luck with your impatiens!
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