Plant Diseases

The best way to keep plants free from disease is to grow them in the right conditions, so that they are strong enough to fight off any infections. Clean and sterilize tools and equipment, and prevent diseases from spreading by taking prompt action. Check symptoms carefully—they may just be signs of stress.

Preventing Diseases

Before buying a plant, check that it is healthy, and where species are susceptible to certain problems, buy cultivars that are disease resistant, if available. Try to plant in ideal conditions in well-nourished soil of the correct type, pH, and drainage for your chosen plants, and with sufficient sun or shade. Also keep them well watered, especially after planting while they establish. At the first sign of trouble, cut off affected parts, and either burn them or take them to your local recycling center. Regularly remove yellowing leaves and fading flowers, as well as diseased leaves that have fallen to the ground, which may cause reinfection if the spores blow onto healthy plants. If space allows, practice crop rotation in vegetable gardens to prevent disease from building up in localized areas.

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Cleaning Solutions

Clean cutting tools, including pruning saws, shears, and clippers, regularly with disinfectant to lessen the risk of disease spreading from one plant to another. Clean and sterilize pots, trays, and other equipment used for sowing to prevent damping-off disease, which causes seedlings to suddenly collapse and die. Use new soil and tap water when sowing seeds. Scrub sap from cutting blades with warm soapy water, and use household disinfectant to sterilize them. This reduces the risk of passing infection between plants. Rinse off old soil and use a baby bottle sterilizing tablet to cleanse containers used for sowing.

Stress and Viruses

It can be diffficult to work out what is wrong with a plant, but some worrying symptoms are a sign that the plant is stressed, perhaps due to a lack of nutrients, or because it has suffered physical or chemical damage. Streaked foliage that does not improve after feeding may indicate a virus. Kill any sap-sucking pests that spread viruses, and discard or burn infected plants.

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