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Using Flour on Plants: Provide Nutrients and Prevent Pests

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Flour is a staple in many households, worldwide and is unknowingly a readily available fertilizer. Using flour on plants is a cost-effective method to grow healthier plants by providing nutrients and deterring pests.

Flour can also be used both as a cleaner and a pest control agent. Using flour on plants will stop grasshoppers and other chewing insects while at the same time adding nutrients to the soil. Flour affects the digestive tract of smaller insects such as aphids and gnats, while its stickiness clogs the mouth of grasshoppers.

This article will explain how using flour on plants will boost their growth and soil health while at the same time preventing pests.

Is Flour Good for Plants?

Using Flour on Plants

Firstly, we will discuss one of the most important facts about using flour in our gardens and felids on our plants as a defender as they are well known for working cleaner of plants.

Sift flour away from a freshly moistened plant. It will plug the leaf stoma, causing the plant to suffer. Flour is good for the soil. But, too much nitrogen in the soil is toxic to plants. 

You should consider the nitrogen balance of the soil before you dump flour into it. Too much flour in the soil can result in too much nitrogen, which can be detrimental to the soil.

Following are the benefits of flour on plants.

The nutrition facts for 1 cup of white flour (125 grams):

Mineral Quantity (mg/g)Used For
Potassium (K)134 mgThe movement of water and nutrients, Regulates photosynthesis
Magnesium (Mg)27.5 mgPromotes photosynthesis and green leaves
Manganese (Mn)0.9 mgRoot growth and resistance to pathogens, Photosynthesis
Sodium (Na)3 mgHelps with metabolism and synthesis of chlorophyll
Calcium (Ca)19 mgProvides structural support to cell walls
Iron (Fe)5.8 mgSynthesis of chlorophyll and Green leaves
Protein12.9 gPlays various enzymatic, structural and functional roles

Are there Plant Nutrients in Flour?

Using Flour on Plants (1)

Flour, provides a significant amount of the nutrients plants require for growth such as carbohydrates, amino acids, and other micronutrients.

The nutrients are similar to using banana peels and rice water on plants.

Although flour is good for the soil, too much nitrogen can be toxic to plants. Therefore, you should consider the nitrogen balance of the soil before you apply flour to it. 

However, too much flour in the soil can result in too much nitrogen, which is detrimental to the soil.

Now let’s have a look at how these nutrients help the growth of plants in soil:


It is a crucial element in plant growth, and it is found in plant cells, plant proteins, hormones, and chlorophyll.


It is essential to transfer energy from sunlight to plants, stimulate early root and plant growth, and hasten maturity.


Potassium boosts plant vigor and disease resistance, aids in the formation and movement of starches, sugars, and oils, and improves fruit quality.


Sulfur is a component of amino acids in plant proteins and has a role in plant energy production. 


It is responsible for plant hormone production, which is responsible for stem elongation and expansion of leaves.


Manganese (Mn) is an essential micronutrient for plant growth and development and sustains metabolic roles within different plant cell compartments. 


Selenium was shown to aid plants cope with stress by boosting the antioxidant potential (SOD, CAT, and GSH-Px) and the synthesis of GSH, PCs, ascorbate, and proline flavonoids alkaloids, and carotenoids in plant cells.

In a nutshell, various nutrients in flour are essential for plants for the growth, development, stress reduction, immunity, and transfer of energy, so using flour compost or flour can add nutrients in many ways. 

In addition, it is an easy and cheap way to increase soil fertility with the protection against insects that are harmful to the plants.

Using Flour to Control Pests

Using Flour for Plant pests

Prevention Against Aphids:

Aphids may transmit viruses from plant to plant on certain vegetable and ornamental plants. They can inject saliva into plants causing yellowing, mottled leaves, stunted growth, curled leaves, browning, low yields, and even death in plants.

This saliva also in some cases accounts for sticky stuff that you may find on plant leaves.

Flour will suffocate the aphids by clogging them up. The theory is that aphids will ingest some of it and when they try to excrete their honeydew, the flour will mix with the stuff and prevent them from excreting.

Following are the steps to do that:

  • Take a cup of self-rising flour, pour it into a small bag, and roll up the top of the bag.
  • Poke a few holes in the base of the bag and sprinkle the flour over the cabbage.
  • Flour pesticide should be applied early in the morning

If there is a heavy aphid infestation, covering the plant with flour is a low-cost and effective solution in defending your garden against the bug.

Using Flour to Prevent Grasshoppers:

Grasshoppers consume their body weight in plant matter every day; thus, this will significantly impact the population.

They prefer young, green growth on vegetable plants, grasses, and annual flowers, because of the ease to eat and digest.

The stickiness of flour clogs up grasshopper mouths and inhibits them from eating.   

Following are the steps to do that:

  • The method of natural grasshopper eradication involves only a single ingredient, which is flour.
  • Dust the leaves of the plants the grasshoppers are eating with regular white flour. The flour will clog the insects’ jaws, making it impossible for them to devour the leaves.
  • Grasshoppers’ jaws will become gummed up as they feed if plant leaves are dusted with flour.

In addition to flour, I use bliss pure neem oil from amazon for a great price. It works great when it comes to shining leaves and provides a layer of protection for plants against known pests. You can find it by clicking here!

Bliss neem oil amazon

Can Flour Prevent Gnats?

A gnat is a tiny flying insect belonging to the dipterid suborder Nematocera, specifically the Mycetophilid, Anisopodidae, and Sciaridae families. Biting and non-biting varieties are available. They usually fly in big groups, which is known as a cloud.

Gnats and other chewing insects will not consume your plants if you use flour. Fill a garden duster or saltshaker halfway with all-purpose flour. Dust the insects and the plant leaves with flour after jiggling the plants to get the insects moving.

Additionally, when applied to the soil, it can create a sticky substance that will trap the tiny flies and their eggs, causing them to eventually die.

Gnat can also be prevented by different watering methods such as bottom watering as well as using sand as mulch which is interestingly very effective.

Is Flour Good for Soil:

Yes, flour can be composted. It will decompose and enrich the soil over time. 

Every food material has a shelf life. Once the flour has exceeded the specified time, it begins to rot and decompose. Self-rising flour and whole wheat flour begin to decompose after 4 to 6 months. 

Green components, fruit peels, and vegetables can all be added to the compost pile to speed up the process.

Furthermore, Protein is found in flour (nitrogen). Nitrogen is a nutrient that is found in both soil and plants and is necessary for plant development. 

Plants cannot grow when there is a lack of nitrogen in the soil, resulting in low agricultural yields. Following are the benefits of flour in soil:

Benefits of Microbes in Flour Compost to soil:

Flour can be composted. Flour contains organic compounds that can be broken down by microorganisms and are prone to deterioration. For Example, Wheat flour contains dietary fiber, B vitamins, calcium, iron, magnesium, phosphorus, potassium, and zinc.

These things decompose into compost, which fertilizes the soil.

Microorganisms assist in the breakdown of organic matter, releasing essential nutrients and carbon dioxide into the soil, fixing nitrogen, and transforming nutrients into mineral forms that plants can utilize.

Can you Clean Plant Leaves with Flour?

As we are already aware, flour is excellent when fighting against insects and other bugs of plants that damage various parts of the body of plants. 

To clean the leaves from bugs and other insects; just fill a garden duster or saltshaker halfway with all-purpose flour. 

Dust the insects and the plant leaves with flour after jiggling the plants to get the insects moving.

In addition to this, you can apply a preventative spray once a week. 

If the potato bugs or larvae have already infested the foliage, use this natural remedy every three days to eliminate the pests. In ecological agriculture, rock flour has created a reputation for itself as a natural soil help.

The Takeaway:

We have listed the facts when using flour on plants, as protection against insects, its nutritional value in soil as well as its use in composting.

Moreover, we also know how much flour you should use to clean the leaves. 

Caution must be taken while using freshly moistened flour because they will plug the leaf stoma, preventing the exchange of gases in the plant.

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