What causes blight?
What is blight exactly? Blight is basically a fungal infection. Theories abound on what actually causes the plant disease. Some say that soil which is nutrient-deficient creates a breeding ground for blight. Others say that a lack of lime is the problem. Finally, many successful gardeners insist that the fungus is bred by heavy rain fall, mixed with humidity and certain soil conditions. Regardless of the exact cause, blight can be detrimental to your crop.
How is blight identified?
Blight can be difficult to spot at first, which in turn may allow the disease to spread and possibly cause significant damage before it is treated. Conscientious gardeners notice blight in its early stages: when small black or brown circles begin to form on the lower leaves of the plant. The spot usually consists of a dark outer ring with a lighter center. As blight spreads, the number of spots multiply and the leaves begin to turn yellow. The fungus moves up the plant, damaging the leaves in its path.
What harm does blight cause?
Blight can completely destroy your tomato crop. If you do not attempt to treat it, your plants may not form fruit or even flower effectively. If you discover blight, you must attempt to treat it.
How is blight treated?
The first step in stemming the spread of blight is to remove all of the damaged leaves. This is a painful process, but it must be done in order to keep the disease from spreading. Wash your hands in between plants so as to keep from spreading blight to healthy plants or leaves. Dispose of infected leaves away from your garden. Blight lives in the ground, and by leaving infected leaves on the soil you will be furthering the spread. You will also need to plant your tomatoes in a different location for the next few years, as blight will continue to be present in the soil.
Next, you must purchase a fungicide that will halt the spread of the blight. Organic growers choose a natural, copper solution, though many other products are on the market. Visit your local garden center, nursery or hardware store to find a fungicide which targets blight on tomatoes. Generally, you will need to dilute the product in water and use a spray bottle to apply it thoroughly to the entire plant. Spray until the plant's leaves are dripping with the solution. Though you should always read the directions carefully, you will probably be instructed to apply it once a week and after rains.
After you begin spray-treating your tomato plants, continue to check for the spread of blight and remove damaged leaves. Though this process is tedious, it is the only way of minimizing the damage to your plants and encouraging as much tomato-production as possible.
Published by Amy Kreger
Amy is a stay at home mom who resides in northern Minnesota. She has been married for 9 years and has 4 young children. View profile
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14 Comments
Post a CommentTry planting some other variety of tomato that is more resistant to fungi. You may need to change to another type of crop.
Remember, copper based fungicides are fundamentally highly toxic to humans, too.
Our food supplies have always been ravished by our competitors, such as fungi, weeds, insects, and rodents, who are struggling for their own survival. Be brutal! Check with your County Agent (or equivalent).
will it affect peppers?
after two years with blight how do I treat the soil to avoid this problem for next year.
I have found a way to stop the blight in its tracks- add two ounches of clorox to each gallon of water and soak the devel out of the entire plant . It will stop the blight and not hurt your plants
what do i do to treat blite.
When buying tomato plants, always look for these letters. VFNT
I have lived in Western PA all my life (now at age 54) and have had a garden much of my adult life. I never heard of this blight before, this is the first year I have seen it and have fallen victom to it. My question is the last few years we have had strange bugs and now strange diseases to our plants why all of a sudden is Western PA having problems? I believe this is a man made problems!!
We started our plants from seed this year but still got blight in on section of our garden. The spores are airborne and you can get them from neighboring gardens so keep a very close watch on your plants and act quickly if you see anything. I have heard of folks going away for a few days and coming back to find most of their tomatoes ruined.
How do I treat the soil after I pulled out all of my tomatoe plants due to blight fungi? What do I need to treat the soil with?
Bought plants at Lowes in Milford, now have blight. Thought it was going great until I checked recentlt. Question...any potential harm to me...breathing in these spores? I did not know this was fungus based disease until after being out there all day with my face in these plants clipping leaves and bad branches.