Detect and Subdue Diseases in the Garden
Is there a doctor in the house?
Plants need to be planted in the proper location. - do you have a plant that needs full sun planted in the shade? Make sure the soil is healthy, has the proper pH level and nutrient balance, and has sufficient drainage and water holding capability. Make sure the plant gets the appropriate amount of water (about one inch per week). Be sure the plant gets the appropriate amount of fertilizer.
Fungus - One of the most common problems with plants is fungal disease. If you had any form of fungi last year, you will probably have it again this year. What do you do?
Water plants before noon Fungi spores can germinate within 6-8 hours. So watering at night may limit evaporation, but can allow a fungus to grow.
Start crop rotation Never plant the same kind of vegetable or flower in the same place two years in a row.
Stop it before it starts If you have had a fungi in the past, it will be back. It usually happens at the same time every year. The best time to start using fungicides, such as Physan 20, is early in the season. Repeat every seven to ten days throughout the growing season.
Bacteria - Other types of plant disease are bacterial diseases. Water and soil are their transportation. They can enter a plant through wounds or through the natural openings in the epidermis (stomata). Generally, they cause rotting and wilting.
Bacterial disease cannot be cured. Infected plants must be immediately removed from the garden. ALL of the affected plants must be removed to the trash can. Even if they have only slight symptoms of bacterial disease. Do not place diseased plants in your compost pile, even if you maintain an active pile that heats up.
To prevent the spread of bacterial disease, clean your pruning tools with a bleach solution made up of one part household bleach to four parts of water, or use Physan 20. Wash your hands after handling infected plants to avoid transmitting the disease to healthy plants.
Viruses - Viral diseases damage the plant by destroying the chlorophyll in cells, causing yellowing of the leaves. If a plant becomes sick and dies within a few days, suspect a virus. Insects often carry viruses to plants, especially aphids, leafhoppers, mealy bugs and whiteflies. Aphids are the worst offenders; the green peach aphid can carry more than 50 different plant viruses.
Viruses can also be carried on your hands or on garden tools. Viral diseases cannot be cured. Remove and destroy the infected plants. Viruses can live on dead plant material for 50 years.
Nematodes - Although nematodes are actually pests, the problems they cause are included with diseases because the problems persist for the life of the plant. Nematodes are tiny parasitic worms that stick their heads in a plant to suck the sap or actually spend their lives inside the plant. Very often, a nematode problem will show up with a plant weakening and not looking healthy and vigorous. If no other explanation seems to fit, check the possibility that your plants have nematodes.
Prevention - There are too many diseases to name them all, but if you can use these disease prevention steps, you can stop most diseases from attacking your garden.
Build healthy soil. - Use compost and plant resistant varieties. Rotate crops, use foliar feeding and mulch. Eliminate the method of transmission of disease by watering plants before noon, keep tools clean and clean up the garden in fall.
Solarize the soil and use drip irrigation to prevent fungal diseases. - To avoid spreading fungal plant diseases, don't work with plants when they are wet. Mow under fruit trees. Remove clippings and leaves to the compost pile.
Plants need to be planted in the proper location. - do you have a plant that needs full sun planted in the shade? Make sure the soil is healthy, has the proper pH level and nutrient balance, and has sufficient drainage and water holding capability. Make sure the plant gets the appropriate amount of water (about one inch per week). Be sure the plant gets the appropriate amount of fertilizer.
Fungus - One of the most common problems with plants is fungal disease. If you had any form of fungi last year, you will probably have it again this year. What do you do?
Water plants before noon Fungi spores can germinate within 6-8 hours. So watering at night may limit evaporation, but can allow a fungus to grow.
Start crop rotation Never plant the same kind of vegetable or flower in the same place two years in a row.
Stop it before it starts If you have had a fungi in the past, it will be back. It usually happens at the same time every year. The best time to start using fungicides, such as Physan 20, is early in the season. Repeat every seven to ten days throughout the growing season.
Bacteria - Other types of plant disease are bacterial diseases. Water and soil are their transportation. They can enter a plant through wounds or through the natural openings in the epidermis (stomata). Generally, they cause rotting and wilting.
Bacterial disease cannot be cured. Infected plants must be immediately removed from the garden. ALL of the affected plants must be removed to the trash can. Even if they have only slight symptoms of bacterial disease. Do not place diseased plants in your compost pile, even if you maintain an active pile that heats up.
To prevent the spread of bacterial disease, clean your pruning tools with a bleach solution made up of one part household bleach to four parts of water, or use Physan 20. Wash your hands after handling infected plants to avoid transmitting the disease to healthy plants.
Viruses - Viral diseases damage the plant by destroying the chlorophyll in cells, causing yellowing of the leaves. If a plant becomes sick and dies within a few days, suspect a virus. Insects often carry viruses to plants, especially aphids, leafhoppers, mealy bugs and whiteflies. Aphids are the worst offenders; the green peach aphid can carry more than 50 different plant viruses.
Viruses can also be carried on your hands or on garden tools. Viral diseases cannot be cured. Remove and destroy the infected plants. Viruses can live on dead plant material for 50 years.
Nematodes - Although nematodes are actually pests, the problems they cause are included with diseases because the problems persist for the life of the plant. Nematodes are tiny parasitic worms that stick their heads in a plant to suck the sap or actually spend their lives inside the plant. Very often, a nematode problem will show up with a plant weakening and not looking healthy and vigorous. If no other explanation seems to fit, check the possibility that your plants have nematodes.
Prevention - There are too many diseases to name them all, but if you can use these disease prevention steps, you can stop most diseases from attacking your garden.
Build healthy soil. - Use compost and plant resistant varieties. Rotate crops, use foliar feeding and mulch. Eliminate the method of transmission of disease by watering plants before noon, keep tools clean and clean up the garden in fall.
Solarize the soil and use drip irrigation to prevent fungal diseases. - To avoid spreading fungal plant diseases, don't work with plants when they are wet. Mow under fruit trees. Remove clippings and leaves to the compost pile.
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