As the end of the growing season is approaching, it will soon be time to pull out and discard any vegetable garden plants that won't survive over the winter. Composting your old plants is a good way to replenish your garden soil with nutrients, so you should compost as much of your garden plants as possible. But, be careful when you pull out any diseased potato and tomato plants, because it may be best to dispose of them in the trash to be picked up by waste management so they won't infect other plants. Some plant diseases when composted can overwinter and emerge again in next year's garden. Here is a tomato and potato plant disease you should dispose of in the trash and one you can compost.
Early blight is a disease caused by the fungus Alternaria solani. This fungus releases airborne spores that can drift for up to 50 miles on the wind. When these airborne spores float into your garden and land on your potato or tomato plants, they can infect them. The fungus can also live on garden tools, pots, and containers, in the soil, and on infected plant debris.
The fungus thrives in warm, damp environments, so as the growing season takes off, so will the fungus. It will usually begin to attack the lower leaves and stems of your plants, turning them yellow and causing dark spots to appear. The disease will progress up the entire plant and even infects the tubers of the potato plant.
The bad part about this fungus is that it can live on plant debris over the winter, especially in a compost pile. Then, when the ground and air warm up a bit, the fungus will begin multiplying again and attack your new crop of tomato and potato plants. For this reason, it is best to bag up any diseased plants instead of recycling them for compost. Dispose of potato tubers and tomato cages in the trash so the spores cannot spread or continue to infect other plants, especially in your garden. (Click here for info on recycling and waste management.) It can also be helpful to treat your garden soil and any other potentially spore-infected areas with a fungicide to eliminate early blight.
Curly Top Virus
The beet leafhopper fly is responsible for spreading this virus that infects plants, such as beets, tomatoes, beans, squash, spinach, peppers, and melons. The beat leafhopper flies around and nibbles on different types of plants, looking for a place to lay its eggs. As it nibbles on one of your garden plants, the virus is transmitted to your plant, which will begin to show signs in about seven to fourteen days. By the time you notice your plant is suffering from this virus, the fly has long gone from the plant.
The beet leafhopper's favorite plants to eat are the tomato and potato, so these are mostly commonly infected by the virus. This virus usually stunts the growth of your potato and tomato plants as soon as the plants begin to show symptoms. The virus also usually makes the leaves curl and turn yellow or brown. It also causes the veins on the underside of your tomato plant's leaves to turn purple, and makes the plant's fruit ripen early. Any infected plants can also die early in the season.
As the plants and their fruit are useless once they are infected, it is best to remove them from your garden. If you do get any fruit from an infected tomato or potato, it is safe to eat it, but it will not have the best flavor. You can compost the dead and dying plants carrying the virus and it is safe to mix them into next year's soil, as the virus cannot be transferred to other plants in your garden.
Use this information as a guide to help you know when you can compost diseased plants and when you need to dispose of them in the trash.