Fungal disease can infect tomatoes in any season. If prevention does not works then fungicide is the next solution. It is easy to find the best fungicide for tomatoes after reading this guide.
Tomatoes belong to the nightshade family. This family is susceptible to many fungal diseases. There is no single hack to control this disease.
Step by step treatment is the best solution against a fungal pathogen. Some common diseases like early blight, late blight and septoria blight attacks on tomatoes in a favourable environment.
Applying fungicides prior to infection is best practice. Once the disease spreads, not easy to control. Some fungicides work efficiently against tomato diseases. Here are some recommendations you should keep in mind while purchasing fungicide.
Contents
Buying Guide – Best Fungicide for Tomatoes
Some times we can not find the best solution for disease due to a lack of chemical knowledge.
Identify disease
Most of the gardeners confuse fungal symptoms. It is recommended to identify disease first. Some fungicides are broad action which works against all fungal disease. There are some viral and bacterial diseases that can infect tomatoes so diagnosing is the first step.
Active ingredient
Inert material and active ingredient are total compositions of fungicide. Check if an active ingredient is anti fugal or not. Here are some common active ingredients.
Copper-based Fungicides
Copper-based fungicides are used for early blight. In Cornell University, it tested against late blight with good results. Copper-based fungicides are usually used as preventative. If you are an organic grower these concentrations are best for you:
- copper octanoate
- copper sulfate
Make the mixture in the tank and spray infected plants with a copper-based fungicide.
Chlorothalonil
It works against late and early blight. It is better to use it as preventive. If your tomatoes plants are subjected to humid or wet conditions, apply the required amount.
Mancozeb
It is a zinc-based chemical. It is not recommended for organic gardens. It also controls both major diseases, early blight, and late blight. Mix this chemical in the tank for better concentration. Apply mancozeb before sprouting. It is better to use in the field.
Maneb
Maneb can be used as a home garden or lawn fungicide. It is also good for organic gardens. It is easy to apply maneb as compared to other chemicals. It usually comes in wettable powder which can be easily mixed with water before application.
Top 7 Fungicides against Tomato diseases
| Fungicide | Best For | Active Ingredient | Check Price |
|---|---|---|---|
| Aliette WDG AG Fungicide | Best Overall | ALUMINUM TRIS | Check Price |
| Zinc Based: Bonide (BND862) | Easy to Use | Mancozeb | Check Price |
| Fung-onil: Bonide (BND883) | Packaging | Chlorothalonil | Check Price |
| Copper-based: Bonide 811 | Easy to Use | Copper Octanoate | Check Price |
| Liquid Copper Fungicide | Quick in Action | Copper diammonia diacetate | Check Price |
| Captan Fungicide: Southern Ag | Best Sold | Captan | Check Price |
Instant Killer: Aliette WDG AG Fungicide
This product is specifically made for blight disease. It can control both early and late blight effectively. Product description mentioned control of Pythium and phytophthora. Phytophthora is the causal agent of late blight and pythium infects roots of tomatoes. Source
Alliette should be applied prior to infection. This is not limited to this fungicide, it is always a best practice to use fungicides prior to infection. You can use in sever condition according to recommendations mentioned on the product.
Alliette is systemic fungicide so never use it with a copper-based fungicide. It is very specific against tomato blight diseases. The application method provides an easy to spray this fungicide.
Zinc Based: Bonide (BND862)
It is best for field or outdoor crops. Bonide is broad-spectrum and protectant fungicide best for blight disease. The shining feature is that it found valuable against severe infection when applied at regular intervals.
It controls all fungal diseases in tomatoes, potatoes, and onions. The active ingredient is zinc. Zinc is very specific in action. Zinc activates specific enzymes that produce protein and immunity.
Some garden owners tested it against 90% infection and still, it worked perfectly. It is recommended to rotate it with diaconal.
If you find humid or cold conditions, it is better to apply this fungicide. Continuous rain can wash it out so apply at regular intervals. The quick action of the product makes it stand out.
Zinc also works as lawn fertilizer. It activates some enzymes which are immune to the disease. It will make your field lush green and kick out all fungus related diseases. The following diseases can be controlled with Bonide.
- Early blight of tomato
- Late blight of tomato
- Septoria blight of tomato
Fung-onil: Bonide (BND883)
Fung onil is also a broad-spectrum fungicide. Some times sever attacks can establish in resistant varieties too, in this case, this fungicide will work effectively.
The active ingredient is chlorothalonil. This active ingredient is specific in action like a copper-based fungicide. It is commonly used fungicides in the united states.
Like other chemicals, this one also has very quick action.it is recommended for high disease severity. In wet or humid conditions you can apply this fungicide as preventive. This product is conveniently ready to use when it arrives. No mixing or pouring required. The spray nozzle makes this product easy to deploy.
Copper-based: Bonide 811
If you find septoria leaf spot, early blight or late blight in your garden, this chemical is the best rescue for your garden.
If you have humid or wet conditions in the garden, apply this chemical prior to infection.
The shining feature of this copper-based fungicide is that it can be used organically. It will not harm pets or any beneficial insects. The biggest problem with most of the fungicide is that they harm beneficial insects like bees or beetle.
If you are a kitchen gardener, this product is suitable for you. Some recommended methods should follow before application. Always apply in the early morning or evening.
If rain washes it out, apply at regular intervals. The product instantly mixes with water and should be applied using either a hose-end sprayer or tank sprayer. This product is listed as a featured product by amazon in the fungicide category.
Liquid Copper Fungicide: Southern Ag
In liquid fungicide, this one is also amazon’s best choice. It is a multi-purpose fungicide.it can eradicate all fungal and bacterial diseases from your tomato plants. Ingredients are very specific and tested.it contains 31.4% Copper Ammonium Complex (8% Metallic Copper Equivalent)
This fungicide is available in concentrated form so mix with water before application. You can use an electric sprayer or tank sprayer for spraying the chemical.
Good thing is that it is not toxic if applied in small quantities. You can eat tomatoes if it absorbs low quantities of copper sulfate.it is nontoxic so you can use it without killing beneficial insects, some pests like snails or slugs are very sensitive to copper.
It is recommended to use this product prior to infection. If you use this product before infection, it will reduce disease severity or can reduce disease.
Captan Fungicide: Southern Ag
Some times we can not diagnose disease, it is the best fungicide for all king of fungi. This product is efficient against every variety of tomatoes.some resistant varieties show mild symptoms can also be controlled with captan fungicide.
Captan is a well-known chemical against all fungal diseases of tomato. Captan is micro-fine powder. You can easily mix this fine powder with water before application. According to recommendations 2 pounds per acre are enough to spray,
This product has less toxicity. You can use this fungicide without harming pets or animals in the vicinity. This will affect honeybees and other pollinators in the garden.
Related: Best Fungicides for lawn
Common Tomato diseases
Viral, bacterial and fungal pathogens can attack tomatoes in favourable conditions. Bacterial and viral diseases are not reported at a high severity rate. Most of the fungal diseases are harmful to potato plants. Here are some common fungal diseases of tomatoes.
- Early blight of tomato
- Late blight of tomato
- Alternaria stem canker
- Anthracnose
- Black mold
- Fusarium wilt
- Septoria leaf spot
Early blight of Tomato
Early blight is the most common disease of tomato. Alternaria solani infects both tomatoes and potatoes. It appears in the whole world in a favourable environment. Older and new leaves are susceptible to attack. Brown spots appear on leaves that look like bull’s eye. Wither and wilting also an extension of this disease. As infection proceeds, these spots will turn yellow.
Fruit and leaves both get infected in severe conditions. This appears early in the season, symptoms can be confusing with the late blight of tomato.
Pathogen overwinter on infected plants or debris. Humid condition. rain splash and irrigation can spread disease. Plants lacking essential nutrients are more vulnerable to attack.
Treatment
- Sow plants in rows and maintain row to row distance. Stake or prune infected plants for air circulation and prevention of the pathogen from overwintering.
- Disinfect pruning parts with bleach and water.
- Keep plant-soil cleaned and dry. Do not apply too much water. Spread a thick layer of compost to prevent splashing of spores
- Use a soaker hose or drip irrigation for efficient watering.
- If you have humid conditions, apply copper-based fungicide prion to infection. This will produce immunity in plants to withstand against disease.
- Bonide @ Garden dust contains both pyrethrin and copper. For best results cover above and below of the leaves.
Late Blight of Tomato
Late blight of tomato is caused by Phytophthora infestans. This disease appears ate in a season that’s why called late blight. Gray-green water-soaked symptoms appear on older leaves. Later these spots enlarge and cover whol leave. Humid conditions with warm temperatures favor the disease.
Wind and rain splashed carry the disease from a nearby field. Infected leaves and debris cause overwintering of pathogen.
Treatment
- Use resistant varieties against late blight of tomato
- Keep proper space between rows. Prune plants and disinfect pruned portion with bleach and water.
- Use drip irrigation or soaker hose for watering. Overwatering can enhance pathogen growth.
- As pathogen overwinter so remove debris and infected plants.
- It is better to apply fungicide prior to infection if the disease appears applies every 7 days with regular intervals.
- Use broad-spectrum fungicides as mentioned in the above list. Broad-spectrum fungicides will show quick results.
FAQ’s
What can i spray on tomatoes for blight?
Use any copper or zinc-based fungicide. You can prepare your own chemical against blight. Take baking soda and mix in water for application. Apply this mixture in te form of spray
Can i use copper fungicide on tomatoes?
Yes, copper is best for early and late blight diseases of tomato. Spray copper sulfate prior to infection. If the disease appears to apply copper-based fungicides with 7 days interval
Can you eat tomatoes with fungus?
If tomatoes are looking healthy in appearance, you can consume them. Symptoms of the common disease appear on tomato surfaces,leave them. Some tomatoes are over-ripened which shows similar symptoms to any disease.
What is the best fungicide for tomatoes?
Different fungicides are available in the market against tomato diseases. Here is some best one to use.
- Zinc Based: Bonide (BND862)
- Fung-onil: Bonide (BND883)
- Copper-based: Bonide 811
Conclusion
It is hard to identify fungal diseases on tomato plants. Early blight and late blight are some common diseases of tomato plants or nightshade family. Best fungicides against them reviewed. Our top selection from the list Zinc Based: Bonide (BND862) which is best for field plants.
Hi i am Waqar Zafar, a passionate plant pathologist. I have done graduation Plant pathology and animal science. My research papers on pest control and plant health phenomenon published in many journals. Research is not limited to some papers as agriculture and farming is a wide field so looking for suggestions from readers.