By Blake Jackson
Wilting plants are a common sight during summer, and many gardeners immediately assume they need more water. However, according to Bruce Spangenberg, Horticulture Outreach Specialist with the UW-Madison Division of Extension, several factors besides dry soil can cause plants to wilt.
Under normal conditions, plants absorb water from the soil through their roots, where moisture naturally moves into the plant because of differences in water concentration.
The water then travels through the stems to the leaves, replacing moisture lost through transpiration. This continuous movement also carries essential nutrients throughout the plant.
Environmental conditions have a major impact on transpiration. During daylight hours, tiny openings on leaves called stomata release water vapor into the air. Hot temperatures, low humidity, and strong winds can dramatically increase water loss.
As a result, plants may droop during a hot afternoon even when the soil contains enough moisture. In many cases, they recover naturally once temperatures cool and wind speeds decrease later in the day.
Water moves through plants using a network of hollow tissues known as xylem. When this system becomes blocked or damaged, plants cannot transport water efficiently, leading to wilting.
Several fungal diseases, including fusarium wilt, verticillium wilt, oak wilt, and Dutch elm disease, invade the xylem and restrict water movement, often causing severe damage or plant death.
Physical injuries can also interrupt water flow. Insects that bore beneath bark, root-feeding grubs, rabbits chewing on tree bark, or accidental damage from lawn equipment may all interfere with the plant’s vascular system.
Surprisingly, plants can also wilt when soils are overly wet. Saturated soils reduce oxygen available to roots, weakening their ability to absorb water despite abundant moisture. Without healthy roots, water cannot move through the plant effectively.
Before reaching for the garden hose, inspect wilting plants carefully. Weather conditions, disease, physical injury, and excessive moisture can all contribute to wilting, making proper diagnosis essential for effective plant care.
Photo Credit: pexels-niko-d
Categories: Wisconsin, General