How To Treat Leaf Spot Disease On Houseplants

For plants that are systemically affected, there is no treatment; these plants should be destroyed.

Any technique that reduces humidity, lessens leaf wetness, or improves air circulation can assist to cut down on the likelihood of infection.

Watering ought to be done in the morning so that leaf surfaces have time to dry fast.

How is the condition known as leaf spot treated?

A typical bacterial or fungal ailment that afflicts houseplants is called leaf spot. It results in unsightly brown spotting that occasionally has a yellow or reddish tint and can quickly spread from leaf to leaf or even plant to plant. This is a common plant killer that can happen for a number of environmental reasons.

A cluster of little brown patches is typically the first indication of an infection. These might occasionally combine to form larger browning patches or they can harden as tiny, reddish-brown spots all over the leaf. Additionally, you might see holes growing inside the discolouration. This is because the infection destroys the tissue of the leaves.

What causes it?

Leaf spot can be promoted to appear in a variety of ways. The most frequent reason is persistently high humidity levels combined with poor air circulation. Watering foliage while sprinkling water on the leaves or over-misting the foliage are other common mistakes. Maintaining a comfortable, constant temperature in the room will help protect your plants from temperature fluctuations. These actions appear to be beneficial, but if not done carefully, they could create the ideal environment for these bacteria and fungi to develop.


  • Trim and remove leaves that are seriously harmed. If there are only one or two spots, skip this step and continue with the next.
  • Neem oil or another fungicide should be applied often to the foliage. Most plants can safely use and benefit from copper-based fungicides, but always do your homework. Some plants may be harmed by copper.
  • As it heals, keep water away from the leaves.
  • Keep the plant separated from other plants for the time being. By doing this, you’ll stop the illness from spreading to your other plants’ foliage.
  • Check each day to see if the virus is no longer spreading.
  • Till you’re sure the plant has beaten the virus, repeat procedures 1 through 5 several times.


Try these advice and techniques to save your plants from leaf spot:

  • Deliver clean air. This can be accomplished by keeping a window slightly open or running an air purifier or fan nearby, especially in the hot and muggy summer months.
  • Avoid splashing or misting. watering your leaves once they are dry. While certain plants (such as ferns and air plants) prefer high humidity and enjoy sprinkling, many others will not tolerate constant moisture because it increases their susceptibility to disease.
  • Give your plants some room. Give your plants additional space so they don’t become crowded and rub leaves against one another. This reduces the likelihood that leaf spot may spread from plant to plant.
  • routine applications of neem. Neem oil can be sprayed on your plants once a month as a preventative measure against bacterial, fungal, and pest problems. This will help you catch any early signs of leaf spot before it gets out of hand.

How can you prevent plant leaf spots?

Although leaf spot infections won’t do major harm to your plants, there are some things you can do to lessen the disease’s impact on the tree in upcoming years.

  • Before the first snowfall, rake up and remove fallen leaves to get rid of any places where illnesses could persist and re-infect the plant the next growth season.
  • Use size at maturity as a spacing reference when planting to avoid overcrowding.
  • To increase light penetration and enhance air circulation throughout the canopy, prune trees or shrubs.
  • Trees should only be watered at the base to prevent illness from spreading, and leaves should not be splashed with water. The best option for this is a drip or soaker hose. Do not use sprinklers.
  • Reduce your tree’s stress by:
  • During the growing season, water your tree to keep the top 6 to 8 inches of soil moist, especially during the dry summer months.
  • Before watering the soil once more, it should have time to dry.
  • Maintain a mulch layer around your tree that is 3- to 4-inches thick.
  • Avoid piling mulch up around the tree trunk; instead, spread it out level, leaving at least 2 inches between it and the stem to allow for airflow.
  • Reapply mulch every year and check to make sure the levels are being kept.
  • Except when a soil test advises it to address a nutrient deficiency, avoid fertilizing trees and shrubs that have leaf spot infections.
  • Unless a tree has lost all of its leaves for a number of years in a row, fungicides are not required.
  • Fungicides must be used before symptoms show up on the leaves since they are protective.
  • Depending on the biology of the disease, different fungicide applications may be applied at different times.
  • To completely cover the canopy of huge trees, high-pressure spraying equipment is required.
  • For the treatment of leaf spot infections in large trees, hire a qualified arborist.

How can leaf spots be treated naturally?

Blend everything in a gallon of water. Every ten days, spray the entire garden. When used on tomatoes and squash, this works incredibly well.

It may be possible to prevent blight by preventing leaves from coming into touch with the soil. Around tomatoes, using mulch or landscaping cloth can significantly lower the occurrence of blight.

Powdery Mildew Remedy

  • a quart of water
  • 2 tablespoons of baking soda/epsom salts or 1 splash of rubbing alcohol

Important: As you move from plant to plant, immerse pruning and gardening tools in a solution of 1 part bleach to 10 parts water to help prevent the spread of illness. With your hands, you can remove yellowed or discolored leaves, but wash your hands afterwards.

How is bacterial leaf spot killed?

Plants may exhibit bacterial leaf spots in a variety of ways. Bacterial leaf spot symptoms can include lesions with black edges, brown spots with yellow haloes, or plain light and dark patches of leaves. The spots are erratic and range in size from 3/16 to 1/2 inch (5 mm to 1 cm). They can develop on the top or bottom of a leaf, and when they group together, they kill off portions of the tissue.

The edges of a leaf may also exhibit the signs of bacterial leaf spot, where the color is brownish yellow and the tissue dries and separates. As soon as the bacterial disease affects the leaf edges, the leaves start to look rather papery and delicate. Older leaves are where the disease is most prominent, but it spreads fast to fresh tissue.

The Double Whammy Lawn Disease:

Many lawn illnesses produced by the same family of fungi go by the popular titles leaf spot and melting-out. There are numerous different disease-causing organisms found in Helminthosporium (wow, that was a mouthful!). The grass diseases in this family all attack your lawn in two phases: leaf spot in the spring and fall, and sheath and root rot in the sweltering summer. This gives your lawn a genuine one-two punch.

When Can You Expect To See Spots?

The fungi that cause lawn diseases survive the winter as mycelium (fungus threads) and spores in and on sick turf tissue. The fungus starts to grow and disperse its spores via wind and water when springtime temperatures reach 55 to 60 degrees and there is lots of moisture from rain or dew. The sickness enters the second stage of melting out as the temperature rises.

Damage Symptoms:

Individual grass blades will have several lesions (or infection marks) that resemble cigarette burns and are dark circles with a tan spot in the center during the leaf spot phase of this lawn disease (spring or fall). The grass develops a brown under cast at this stage of the leaf spot lawn disease, making it appear underfed or dried out. Although leaf spot does not cause much harm to the turf at this stage, it prepares the ground for the melting-out phase, which causes considerably more severe damage.

Large uneven portions seem dried out during the melting-out phase, which starts when it is hot and dry outside. During the melting out phase, there might not be any overtly noticeable lawn disease signs because the damaged regions might resemble those caused by dry weather or insect damage.

Early Action Needed: Don’t Snooze, You Might Lose

The way the turf is irrigated, fed, and mowed makes a significant difference with all lawn illnesses. It is better to avoid allowing the grass to become overly moist or dry out continuously.

Water only once a week at a maximum depth of six inches. Water the lawn in the morning to prevent it from staying soggy for too long. Use core aeration to ventilate the region surrounding the grass crowns, where the plant penetrates the thatch and enters the soil. Regular lawn aeration and fertilization can help avoid disease. Additionally, gathering the cuttings in the spring and fall will assist stop the spread of illness (leaf spot stage).

If necessary, lawn treatment services should start right away. Fungicide sprays in the spring and early summer can be useful, but after the melting-out phase starts, little can be done to stop grass disease.


  • Leaf spot gives turf a sickly appearance but does little lasting harm. But it prepares the ground for the illness’ more dangerous melting-out stage.
  • Water early in the day so that the grass may dry out rapidly. As a result, leaf spot spores are less likely to spread.
  • Melting out happens in warmer temperatures and is readily mistaken for bug or drought stress.
  • Regular lawn aeration and thatch control keep turf crowns open and lower the occurrence of disease.

Contact your local Spring-Green if you have a query about leaf spot (or any other lawn disease). The solutions are here!

Should I remove leaves that have brown spotting?

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We’ve experienced our fair share of brown, decaying leaves as we’ve learned how to properly care for various home plants over the years. We weren’t sure at first whether to take them out or leave them. Here is what we’ve discovered works the best.

Do you need to remove the dead leaves? Yes. Your indoor plants should have brown and withering leaves removed as quickly as possible, but only if they are more than 50% damaged. By removing these leaves, the plant looks better and the healthy foliage that is left can receive more nutrients.

Even though it might appear straightforward, there’s more to it than merely cutting those leaves off. To keep your plant healthy, you must assess how much of the leaf is dying and then carefully remove the damaged areas.

Which fungicide works the best against leaf spot?

The best results for spring and summer leaf spot are obtained with preventative fungicide applications or with applications made just as the disease is beginning to manifest. Leaf spot illnesses are often well controlled by products containing iprodione, chlorothalonil, mancozeb, fludioxonil, azoxystrobin, or penthiopyrad.

When should leaf spots be sprayed?

To avoid chemical contact with your eyes or skin when handling chemicals, we advise wearing the appropriate safety gear for the task. Long sleeves, safety eyewear, and gloves should be sufficient.

Patch Pro is the solution we suggest most for eradicating leaf spot. Propiconazole, the product’s main ingredient, successfully eradicates Leaf Spot and prevents it from spreading. It is also one of our most reasonably priced fungicides and is cost-effective.

You must compute the target area’s square footage to decide how much Patch Pro you require. You must calculate the square footage needed for this by measuring the length and width of your lawn. The recommended dosage for Patch Pro to treat Leaf Spot is 1 to 2 fl oz per gallon of water per 1,000 sq ft. For instance, to treat 2,500 square feet of yard, combine 2.5 to 5 fl. oz. of Patch Pro with 2.5 gallons of water.

Add half of the necessary water to a pump sprayer, then, based on your calculations, add the right amount of Patch Pro. Then, after adding the remaining half of the necessary amount of water, close the lid and shake the sprayer to thoroughly combine the solution. Your time to spray has come.

Spray Patch Pro onto Leaf Spot infection-affected areas (not to the point of runoff). Spring is the ideal season to start spraying Leaf Spot. Patch Pro must be used as a preventative measure before the fungal spores are disseminated to the leaf in order to be successful.

The majority of Leaf Spot fungi attack trees in the early spring, right as the leaves are beginning to appear. In order to stop the spread of the spores, you should also make sure to spray nearby vegetation.

Return a few days later to see if the application is still operational. To maintain continuous control of leaf spot, you might need to reapply fungicides at intervals of 14 days. If you start to notice the symptoms again, retreat.

How do you tell a bacterial leaf spot from a fungal leaf spot?

Put leaves in a moist room and look for fungal structures (little black dots in the lesions) after two to three days to distinguish between bacterial and fungal leaf diseases. Additionally, before bacterial sores dry out, they will be “water-soaked” or “glassy,” especially if the surrounding air is humid.

How can brown stains on houseplants be treated?

Dark brown, slightly sunken, and moist-appearing leaf patches could indicate bacterial leaf spot on your plant. Sadly, this is not good news.

Solution: To prevent the infection of other plants, first isolate your plant. Your plant should dry out once you remove any leaves that have stains on them. When the top two inches of soil feel dry, only water it. In mild circumstances, this approach might be effective, but in extreme cases, it might be advisable to destroy the plant.