The statement ‚”Start with healthy soil” should be at the forefront of every gardener’s mind whether he are planting his first or his twenty-first vegetable garden. Beginning with healthy soil prevents unseen problems in the vegetable patch later in the season. Cabbage plants are particularly susceptible to many of these problems. With proper care, cabbage is easy to grow. The list of plant diseases found below are not only found on cabbage plants, but may be found throughout the vegetable patch.
Ten Cabbage Plant Diseases
- Bacterial Wilt causes plants to wither and die. It is present in plants that have been damaged by insects or human error such as chopping too close with a hoe. A bacterium enters the plant through wounds gumming up the plant tissue, which prevent water from traveling through the plant. All infected plants should be pulled out and burned. Check plants often for damage causing insects and practice a good plant rotation schedule for all Brassicas to limit pests.
- Blackleg is a fungal or bacterial infection, which causes the leaves to turn yellow; stems turn black, rot and die. Pull out and burn all affected plants. Check plants for pests and injury where infection may enter.
- Clubroot is caused by a fungus, which lives in neutral to acid soil compounding this problem is the fact that this fungus may survive in soil for more than two decades. It is most noticeable on days when the weather is hot and dry. The leaves will lose their dark green color, fading from green to yellow and fall from plants. Pull out and burn diseased plants. Hydrated lime may be worked into soil about six inches deep to bring the pH level up to the optimal range of 7.2 – 7.5.
- Damping Off is a fungal disease, which causes seeds to decay before they emerge from soil and seedlings to become soft and rot. Seedlings fall over and die. To prevent damping off in the garden, sow only healthy seed in well-drained healthy soil. Allow plenty of space for air circulation between seedlings. Water in the morning, rather than in the evening, which will allow time for soil to drain before nightfall.
- Downy Mildew is a fungal disease seen most often when weather is damp. Leaves are prone to wilt and die. Tops of leaves have spots that start out green-yellow then turn brown. Bottom of leaf is more than likely covered with grayish colored mildew. Spraying plants with approved fungicide, one containing copper, every two weeks during damp weather seems to help. *Be certain any spray used on edible plants is safe for humans.
- Fusarium Wilt, more commonly known as ‘the yellows‘ is a fungal disease most often seen where weather is warm to hot during the growing season. An infected plant will turn yellow at the stem base and its leaves will wilt then die. Pull out and burn infected plants. Plant only healthy, certified plants or seeds in the future because there is no treatment for this fungal disease.
- Nitrogen Deficiency causes plants to become weak, lose their color; fading from a healthy dark green to a pale yellow or yellow-green. If left unchecked, leaves dry, turn brown and die. Simply work compost into garden soil in the fall and side dress plants with high nitrogen organic fertilizer during the growing season.
- Powdery Mildew is a fungus, which causes a powdery coating over all areas of plants. When nights are cool and damp and days warm and dry, this mildew quickly covers plants. Set plant out in a sunny location where air circulation is good. Begin spraying bi-weekly with sulfur as soon as mildew is spotted. *Only use sprays certified safe for use on edible plants.
- White Mold is a fungus that causes plants to yellow and die. Stems and leaves become covered with white mold and then rot. This is another disease, which survives the winter by living in the soil and attacking plants the following spring. Pull and burn afflicted plants and utilize rotation planting to prevent spread.
- Virus Diseases cause stunted, unhealthy plants with rolled, irregular, crinkled, yellow, spotted or streaked leaves. Viruses enter plants through openings caused by insect pests. Infected plants should be pulled and burned to prevent damage. Monitor garden for harmful insects destroying them as they appear.
Remember to begin with healthy soil and be certain to plant cabbage in rotation to eliminate the spread of disease found in soil where these plants are grown. To read more about the pests found in the cabbage patch, read the article; ‚”Pests Found on Cabbage Plants.”