Inspect the plant for signs of overwatering or underwatering. Both can cause wilting. Over-watering leads to yellowed leaves that droop and fall off, while under-watering leads to yellow and brown leaves that shrivel up. If the plant pot feels very light and the soil feels dry, the plant might not be getting enough water. If the plant pot feels heavy and the soil seems soaked, the plant might be getting too much water.
Water the plant more or less, depending on whether it seems like it is getting too much or too little water. Let the soil dry out somewhat between waterings, and then water the plant thoroughly. Do not allow the flower to dry out between waterings to the point of wilting, and do not water the plant if its soil is still saturated from the last recent watering.
Repot the flower into soil with good drainage and a pot with drainage holes if its current immediate environment does not allow excess water to drain out of the pot.
Inspect the flower for insects with a magnifying glass, especially near wilting parts of the plant. Aphids, beetles, spider mites, mites, thrips and other bugs sometimes suck juices out of plants, causing them to wilt.
Remove any large insect pests by hand.
Spray the flower to wash away small insects.
Wash the plant with an insecticidal soap or horticultural oil to help cure current infestations and prevent future insect problems.
Introduce a natural predator, such as aphytis wasps to eat aphids, or ladybugs — which eat mealybugs and whiteflies as well as aphids.
Check the flower for symptoms of the fungal disease verticillium wilt. Symptoms include yellowing of the plant and drying, starting at the base of the plant. Plants infected with verticillium wilt also have a brown discoloration inside their stems, which is visible when the stems are cut open.
Remove an infected flower from a garden to keep the fungal spores from spreading to other nearby plants.
Destroy the plant. Plants with this fungal disease cannot usually heal.