Natural Fungicide For Plants

Natural Fungicide For Plants

Natural Fungicide for Plants in your balcony

Fungal infections are the most common among the many varieties of plant diseases that are the nightmare of every farmer. You might be afraid to use pesticides on your farm because of the bad reputation they have gained over the years and this is where natural products come in. If you want to maintain good plant health and adhere to organic growing standards, then using natural fungicides for plants is the best option.

You should know that natural fungicides are not made from synthetic chemicals and therefore are safe for your plants if applied properly. In this article, we will discuss the certified natural fungicides, how they are applied, and their importance to plants.

Sulfur Fungicide

Sulfur is probably the oldest natural fungicide that has been used for over 2,000 years. It is effective in a wide range of fungal infections which includes powdery mildew, rusting, and rose black spot among many others. It works by preventing spores from germinating. Therefore, for effective results, you must apply it before the fungal infection develops. You can find it in your local store and is packed as dust, wet powder, or liquid.

You should not apply sulfur if you have used oil spray within the last one month as the two are phytotoxic (can kill your plants) when combined. You should also not use sulfur when temperatures are likely to exceed 80% to minimize the risk of plant damage. Additionally, there are some “sulfur-shy” plants like, apricots, cucurbits, currants, raspberries, and gooseberries that you should never use sulfur in their treatment.

Lime-sulfur is another form of sulfur mixed with calcium hydroxide that can damage your plant foliage and thus should be used as a dormant spray. At a lower concentration, it is more effective than elementary sulfur but its bad odor (like that of rotten eggs) discourages its usage on large scale.

Copper Fungicide

This is another effective fungicide but you should be very careful when using its products as it can damage the host plant. To neutralize the acidity of copper, there is a mixture known as the Bordeaux mixture which is a combination of copper sulfate and calcium hydroxide. The Bordeaux mixture which is both a fungicide and a bacteria has been used for over 150 years and has been effective against infections caused by fungi and bacteria.

Bordeaux mixture can adhere to plants and persist through spring rains. This mixture comes in different formulations but the most effective and least phytotoxic is the 4-4-50 formulation. The numbers are simply the quantities of the elements in the mixture, 4 pounds of copper sulfate, 4 pounds of calcium hydroxide, and 50 gallons of water. 

The formulation was developed to neutralize the acidity of copper. There are other weaker and more dilute formulations that you should apply during the spring after the plant has broken dormancy to reduce injuring the host plant.

The Bordeaux mixture can make leaves turn yellow and fall is applied on temperatures above 85% F. You can prevent the burn risk by diluting the product with spray oil to reduce the strength of the product by half. So, it is always advisable that you should read the product label carefully. 

 Horticultural and Neem Oils Fungicides

These work slightly differently as they are used to control insects that transmit fungal infections. They protect your plants against infections such as mildew. Oils are considered the safest as they are less phytotoxic if you carefully read the given instructions on the labels.

They should however not be applied when temperatures exceed 90% F or fall below 40%. The humidity should also be relatively less than 65% to aid quick evaporation of the oil. Some plants such as black walnut, maples, Japanese and red maple are very sensitive to oil.

Bicarbonates Fungicide

Sodium bicarbonate (baking soda) is a natural fungicide that has been used since 1933. However, research has shown that despite it being effective, the sodium in it can be toxic to plants if it accumulates. Furthermore, sodium bicarbonate is ineffective against many plant diseases in the absence of oils.

Therefore, ammonium bicarbonate and potassium bicarbonate are recommended as they can be used without oils. These two bicarbonates provide nutrients such as potassium and nitrogen to your plants, unlike baking soda which intoxicates plants with sodium. You can purchase the two from your local store or online outlets. 

Bacteria Fungicide

These are the latest development that contains bacteria and other microbes. They are also called bio-fungicides and works in a variety of ways which include; preventing further invasion of fungus, ingesting, and producing toxins that act against them. These fungicides are effective in preventing the spread of pathogens but their application on affected plants can also be noticed. 

Spraying of the fungicide after the plant has already been affected will be less effective except if the infection is moderate. You should store these sprays under a constant room temperature since they contain living organisms. This is to prevent the reduction of the microbes that can die if the spray is left outside where temperatures fluctuate.

Recommended Fungicides in the Market

Grower’s Ally – It maximizes yields by killing and preventing common pathogens like powdery mildew. It is a zero pollutant as it doesn’t contain any synthetic pesticide or heavy metal. It can also be applied through all stages of plant growth and is suitable for all growing environments. You should spray this product for 5-10 days whether you are using it for prevention or treatment.

Safer Garden Fungicide – It’s a fine powder containing 90% elemental sulfur that is effective against brown rot, rose black spot rust scab, and powdery mildew. You can dust it over the plants or mix three tablespoons with a gallon of water and spray. You should not apply it under high temperatures or two weeks after applying oil spray. 

Dr. Earth – It boosts plant growth and root development by providing minerals and micronutrients. It also improves the taste of vegetables. You should mix one cup in a gallon and spray ten square feet when preparing soil or a quarter cup with five gallons of potting soil. You should top-dress a cup in ten square feet for established crops.

Banish – This one uses the power of geranium oil to control mildew in plants. It is effective in controlling various downy and powdery mildew. You should spray it in the morning and evening hours.

Organocide – This one is effective in a large variety of plants infections such as leaf spot, stem and root blights, root rot among others. It boosts plant growth rate and is environmentally friendly. For folia application and soil drenching, you should mix a half teaspoon with a gallon of water and spray weekly.

How Do You Make Homemade Antifungal Spray for Plants?

If you didn’t have a budget for natural fungicide, worry less for you can make your own using simple readily available ingredients. These homemade natural are mostly prepared from oils and soap and thus are way much cheaper.

Baking Soda Spray – You only need three ingredients; 2 tablespoons of baking soda, 1 teaspoon of mild soap (should not contain phosphates), and a gallon of water. Simply mix the ingredients thoroughly. Transfer the mixture to a spray bottle and shake vigorously. Once it’s ready, spray all the sides of the affected leaves. Also, spray the small new leaves to prevent them.

Neem Spray – Wash 100gm of neem leaves thoroughly with running water. Crush them into a fine powder using a grinder. Mix the resulting powder with 100 ml of water. Transfer to a spray bottle and spray the infected leaves. Use the same procedure to prepare garlic and ginger spray.

Clove oil Spray – Get clove oil from your local store and dissolve it in 100 ml of soap water. Add distilled water and spray it on your plants. This prevents the fungus from spreading and further germination. You should follow the same procedure when preparing Cinnamon oil spray which has antimicrobial properties.

Safety Measures When Spraying Natural Fungicides

In whatever you do make sure that your safety comes first. This should apply even when you are taking care of your balcony garden. Rubber gloves are recommended when handling these chemicals for the safety of your hands. Respirators and eye protectors should also be paramount.

You should thoroughly wash your hands with soap and running water then rinse them with a dry cloth after applying these chemicals. You should keep children out of your workplace as some are very mischievous. 


Managing fungal infection is a critical challenge that should be handled with a lot of care to avoid harming your plants. Seeking advice from experts and doing your research by reading helpful articles like this one will help you make the right decisions. 

With this information, you have can now determine which product to go for as well as how to use it and the expected results. If you didn’t have a budget for fungicides, you have now learned the simplest way of doing so.