Michigan State University Extension
Ornamental Plants plus Version 2.0 - 00001486
01/01/98
Blight or fire causes small, brown flecks in the leaves. When the bulb is infected the plant is pale yellowish- green and the flower blasts. As the rot develops it causes a light gray discoloration, bordered by brown margins. The stems may rot off completely. A gray mold may cover the infected area. Do not plant diseased bulbs. Remove the bulb husks to look for diseased spots. Destroy diseased plants. The disease is caused by Botrytis tulipae.
Crown rot causes rotting the bulb and stem below the ground. The leaves turn red, wilt and die. The problem is usually not very common.
Gray bulb rot causes the plants to fail to emerge in the spring or they may emerge, wither and die. Rotted bulbs are covered with heavy gray mold. Avoid poorly drained soil and remove infected plants.
Stem rot and flower spot is most often seen on double flowered varieties grown in moist shaded areas with poor air circulation. The flower stalks shrivel causing the flowers to fall over.
Tulip breaking virus causes irregular spotting and striping of flowers. The leaves may be mottled and the plants reduced in size and vigor. Control the aphids which carry the disease and destroy infected plants.
Winter injury occurs when bulbs are planted late, in heavy clay, or where drainage is poor. The roots fail to grow and the shoots are distorted and abnormal. The bulbs will decay.