Garden Guides, Tiny Black Bugs on Tomato Plants
Tiny Black Bugs on Tomato Plants
- 1 Tiny Black Bugs on Tomato Plants
- 2 Types
- 3 Identification
- 4 Significance
- 5 Time Frame
- 6 Prevention/Solution
- 7 Fighting Tomato Blight
- 8 Black Bugs on Tomato Plant – How to Get Rid of Aphids and Flea Beetles
- 9 Homemade Natural Spray for Flea Beetles on Tomato Plants
- 10 Garlic and Pepper Spray
- 11 Alcohol and Soap Spray
- 12 Homemade Traps
- 13 Cultural Care Considerations
- 14 Additional Possible Flea Beetle Controls
- 15 Tiny Black Bugs on Tomato Plants
- 16 Aphids
- 17 Aphid Control
- 18 Flea Beetles
- 19 Flea Beetle Control
- 20 How to Kill and Prevent Flea Beetles in Your Garden
- 21 Identify Flea Beetles in the Garden
- 22 Control Flea Beetles
- 23 Prevent Future Infestation
- 24 Tomato Diseases: How To Fight Anthracnose
- 24.1 About Anthracnose
- 24.2 Causes And Symptoms of Anthracnose
- 24.3 Treatment and Control of Anthracnose
- 24.4 Common Questions and Answers About Anthracnose
- 24.5 Can anthracnose kill trees?
- 24.6 Can you eat tomatoes with anthracnose?
- 24.7 Does anthracnose stay in soil?
- 24.8 Does neem oil kill anthracnose?
- 24.9 How do you treat anthracnose on tomatoes?
- 24.10 Is anthracnose harmful to humans?
- 24.11 What are the symptoms of anthracnose?
- 24.12 What causes anthracnose?
- 24.13 What does anthracnose affect?
- 24.14 What does anthracnose look like?
- 24.15 Want to learn more about Anthracnose on tomatoes?
By: Kenneth Black
21 September, 2017
Though little black bugs on tomato plants may not seem like much of a problem, if left unchecked the issue can become quite serious. These small pests likely belong to a family of bugs called flea beetles. There are a few different options on how to control them, though some type of pesticide will likely be necessary.
There are dozens of species of bugs commonly referred to as flea beetles. All come from the same scientific family, Chrysomelidae. Though the beetles have a quite extensive list of species, it could be that only a handful live in your area. Regardless of the type of flea beetle, the treatment method is typically the same, as are many of their habits. Not all types like tomato plants.
The flea beetles range in color from black to brown and are generally less than half an inch long; some may be even smaller than that, even as small as one-tenth of an inch. A single beetle, given its size, would not be able to do much damage to any plant as large as a tomato plant, but they are found in groups. Many may infect a single plant. The beetles have well-developed hind legs and can jump an impressive distance if disturbed.
The main threat from these bugs is simply the damage they can do to the tomato plant. The beetles will feed on the leaves and lay their eggs in the soil around these plants. Once the young beetles hatch, they will spend some time in the soil, where they feed on the roots and underground stems of the plant. In addition to defoliation, the beetles can expose a plant to blight and disease, which could be fatal.
Adult beetles typically seek shelter from the winter in the soil, emerging again when the temperature reaches approximately 50 degrees. Once they emerge, they immediately seek food and continue their life cycle. In a growing season, it is not uncommon for as many as three generations of the beetles to come and go, multiplying each time. In locations with extended growing seasons, some beetles produce many more generations each year.
You may be able to encourage the beetles to move on by delaying planting tomatoes as long as possible. If the beetles cannot find nourishment, they will quickly move on. However, if there are other sources of food in the area, they could stick around. Insecticides containing permethrin, carbaryl, spinosad or bifenthrin are effective at wiping out populations. You may need to reapply these weekly to help keep the problem from returning, especially if you have younger plants.
Fighting Tomato Blight
Keep blight diseases at bay in the home garden by following these prevention tips.
Tomato blight can quickly destroy tomato and potato crops.
Photo by: Photo by Mick Telkamp
Photo by Mick Telkamp
Tomato blight refers to a family of diseases caused by fungus-like organisms that spread through potato and tomato foliage, particularly during wet weather. Blight spreads quickly, causing leaves to discolor, rot and collapse. The two best known varieties are early blight, caused by Alternaria solani fungal spores and late blight, a result of Phytophthora infestans spores («Phytophthora» aptly translates to mean “plant destroyer”). The former striking early to mid-season and the latter mid-to-late, blights are the bane of many home growers, rapidly attacking tomato plants and abruptly halting production as it spreads quickly through the garden.
Early blight is characterized by concentric rings on lower leaves, which eventually yellow and drop. Late blight displays blue-gray spots, browning and dropped leaves and slick brown spots on fruit. Although the diseases are caused by different spores, the end result is the same. For tomato and potato growers, blight can be devastating.
As temperatures rise and rainfall increases, risk of infection is high in home gardens. The best offense is a good defense when contending with tomato blight. An undetected infection can quickly put an end to summer tomato and potato crops, but steps can be taken to rescue at-risk plants. If tomato blight has reared its ugly head in the garden this year, a change in maintenance and tactics to limit the spread of the disease may prevent drastic plant losses.
Select resistant plants. Some tomato plants have been developed to reduce susceptibility to blight issues. When purchasing plants, look for blight-resistant varieties and always purchase from reputable sources.
Rotate crops. Plant tomatoes in a different part of the garden each year and avoid planting near potatoes, in which late blight may overwinter.
Allow space between plants. Blight thrives in wet conditions. Give plants plenty of room to provide good airflow and use stakes or cages to keep vines off the ground.
Mulch. Applying mulch around the base of tomato plants cuts back on the spread of spores that cause blight. If blight becomes a problem, surrounding mulch may harbor spores and should be disposed of off-site (do not compost infected plants or mulch).
Water from below. Using drip irrigation or soaker hoses to water the soil around the base of plants helps keep foliage dry, cutting back on the spread of blight.
Inspect plants frequently. Catching blight early can be effective in preventing spread between plants. If blight is detected on shoots or leaves, remove them from the plant and dispose of diseased foliage off-site. Blight spreads quickly, and in some cases destroying entire plants may be necessary to protect adjacent crops.
Treat organically. Copper fungicides can be effective in combating blight, but must be carefully applied. Follow manufacturer instructions, wear protective clothing during application and always wash fruit before consumption.
Black Bugs on Tomato Plant – How to Get Rid of Aphids and Flea Beetles
It’s easy to grow tomatoes in your backyard, but the hard part is to protect them from insects. Like you, flea beetles or aphids enjoy the flavor of red tomato and the bacteria carried by these small black bugs can cause more damage to your tomato plant.
However, with simple home tricks you can prevent black bugs on tomato plant. Apart from natural pests there are companion plants that will either repel bugs or attract helpful insects to protect tomatoes.
What are little black bugs on tomato plants?
There are several pests that attack your ripe tomatoes, but the most common among them are aphids and flea beetles.
- Aphids are small insects that feed on tomato and spread infection to your plants. Leaves affected by aphids turn yellow and then curl.
- There are several types of aphids varying from color (black, pale green and pink) and size.
- This pinhead size insect can also spread virus to your tomato plant.
So, how to control aphids?
Wipe black bugs using string stream of water or with hand after wearing gardening gloves.
Horticultural oils are prominent for its efficiency to control pests. Using this pesticide you can get rid of aphid eggs.
You can also grow companion plant that helps to repel aphids and other insects. Or you can just grow your army to fight aphids. Insects like lady beetles, soldier beetles and syrphid flies protect your garden from black bugs.
- Flea beetle is another commonly found insect that damage tomato plant. These tiny insects are found in different colors like black, brown or blue.
- Measuring about 1/10 inches, young flea beetles feed on underground parts of the plant. Though mature plants overcome this damage, young plant can’t withstand and they suffer the most.
- Adult flea beetles damage leaves by making holes in foliage and resulting in early blight.
How to control your tomato plant from flea beetle?
Regularly remove weeds and debris around the plant; this will avoid adult black bugs to overwinter.
You can also use row covers to protect young tomato plants. Spraying natural pesticides can help to control flea beetles.
How to Protect Tomato Plant from Black Bugs?
If you ignore to take certain steps, you will be not going to harvest too many tomatoes at the end.
#1 Support your tomato plants with steel cylindrical cones. The cage helps to elevate branches and leaves. It also prevents blossom-end rotting.
#2 Plant herbs like basil, cabbage, marigold or nasturtiums beside tomato plants to repel aphids and flea beetles.
#3 Aphids or black bugs feed on weeds, so pull down weeds surrounding your tomato plant.
#4 You can just pluck large insects using gardening gloves, but tiny black bugs should be removed by spraying natural pesticides.
Homemade Natural Spray for Flea Beetles on Tomato Plants
Flea beetles are generally most problematic on young or recently transplanted plants.
Ryan McVay/Photodisc/Getty Images
One potential pest of tomatoes and various other garden crops and ornamentals is the flea beetle. These insects, which are usually dark-colored and about 1/16 inch long, jump like fleas when disturbed and can chew a large number of small holes on tomato leaves. Various homemade sprays and cultural controls can help to limit the presence and impact of this pest.
Garlic and Pepper Spray
A potent spray containing garlic and pepper can repel flea beetles and a variety of other pest insects. To make this type of spray, about six garlic cloves are crushed and blended with a tablespoon of cayenne pepper powder or a similar hot pepper powder or sauce, then combined with a quart of water before the solids are strained out. The resulting liquid is combined with a tablespoon of biodegradable dish-washing liquid in a spray bottle and sprayed onto the tomato. It is important that the spray is reapplied every few days and following any rainfall.
Alcohol and Soap Spray
One spray that may repel or kill flea beetles is made by combining 2 parts rubbing alcohol, 5 parts water and 1 tablespoon of mild, biodegradable liquid dish-washing soap. As with any other homemade or commercially available pest control spray, testing the spray on a few leaves first and monitoring for any burn or damage before treating whole plants is a good idea.
Homemade flea beetle traps are made using 4-inch by 6-inch or larger rectangles of cardboard that are painted white or yellow and then coated with a sticky substance such as petroleum jelly or nonsetting glue. Traps are then held over the tomato plants while the plant is shaken lightly, disturbing flea beetles, which are then caught on the trap. You can also attach the trap to a wooden stake near the plant.
Cultural Care Considerations
Certain cultural care practices can reduce flea beetle presence, minimizing the need for control later. Removing and disposing of or destroying all weeds and crop debris from around the growing area eliminates flea beetle habitat between growing seasons. Young plants are potentially protected using floating row covers, gauze or mesh. Flea beetles love hot sun and dry soil, so planting tomatoes and other vulnerable crops where they can receive some shade and maintaining an evenly moist soil surface is helpful. Flea beetles are especially drawn to plants in the cabbage family, so planting a few of these plants nearby can draw the pests away from the tomatoes.
Additional Possible Flea Beetle Controls
Sprinkling wood ashes or wood ashes mixed with slaked lime or soot around tomatoes and other vulnerable plants may offend flea beetles. Sprays made from kaolin clay may serve a similar purpose. Using a handheld vacuum to remove flea beetles from the tomato plants daily can also reduce pest numbers.
- University of Vermont Extension: Flea Beetles
- Sierra Club Canada: Pest Control Spray You Can Make in Your Kitchen!
- Capital District Community Gardens: Garden Pests & Diseases
- The Old Farmer’s Almanac: Flea Beetles
- Rodale’s Vegetable Garden Problem Solver; Fern Marshall Bradley
- Back to Basics: A Complete Guide to Traditional Skills; Abigail R. Gehring
About the Author
Angela Ryczkowski is a professional writer who has served as a greenhouse manager and certified wildland firefighter. She holds a Bachelor of Arts in urban and regional studies.
Tiny Black Bugs on Tomato Plants
Tomatoes can be eaten raw, used in recipes or made into juice.
Tomatoes provide health-protective nutrients, such as lycopene, and are easy-to-cultivate, making them a popular crop for home gardens. Tomatoes host several insect pests, but aphids and flea beetles are the small, black insects often seen on plants.
Those little black bugs on your tomatoes could be aphids. Aphids are tiny insects that are pinhead to match head in size and range in color from white to pink, pale green and black. Several types of aphids feed on tomatoes and cause damage by sucking sap from the plant and secreting honeydew, which leads to sooty mold. Leaves infected with aphids turn yellow, wilt and curl. Aphids are also known to spread plant viruses.
Gardeners can blast aphids off leaves with a strong stream of water or wipe them off by hand. Beneficial insects, such as soldier beetles, lady beetles, syrphid flies and lacewing larvae can help control the aphid population. Insecticidal soap may also be used, but it is only effective with thorough foliage coverage and can take more than one application to rid the plant of aphids. Horticultural oils are effective on overwintering aphid eggs.
Flea beetles feed on many garden vegetables, including tomatoes. These tiny insects measure about 1/10 of an inch, are black, blue, bronze or brown in color and jump like fleas. Adult flea beetles chew small holes in foliage, making plant tissue more susceptible to early blight. Plants often outgrow damage caused by flea beetles. Flea beetle larvae feed on underground plant parts. Young plants suffer the most from an infestation, but mature plants can withstand the infestation without affecting fruit production.
Flea Beetle Control
To control flea beetles, keep the planting area free of weeds and other debris where adult pests overwinter. To protect young plants, use row covers. If necessary, insecticides are available to help control the pest. Use a product that contains carbaryl, azadirachtin or diatomacecus earth.
How to Kill and Prevent Flea Beetles in Your Garden
Newly planted seedlings offer so much promise. You transition them from the safety of indoor grow lights or a greenhouse to the great, unprotected outdoors. Then you check them morning, noon and night to make sure they are safe and healthy. Everything looks great, until one day you notice a number of tiny holes on plant leaves. A closer inspection reveals small, shiny flea beetles causing this damage.
Even when these beetles don’t kill your seedlings, they can help spread diseases, such as bacterial wilt and blight, from plant to plant — and destroy common garden crops, including eggplant, tomatoes, cabbage and other vegetables. 1 So when these pests arrive, take immediate action to control them.
Identify Flea Beetles in the Garden
Named for their jumping ability, flea beetles emerge from the soil in large numbers when the temperatures near 50 degrees Fahrenheit. 2 These ravenous pests range in length from 1/16 inch to 1/4 inch and are black, bronze, blue or brown, depending on the species. 3 Some types of flea beetles also have stripes. All species have powerful back legs that allow them to jump like fleas when disrupted.
Control Flea Beetles
At the first sign of flea beetles on your plants, turn to a trusted pesticide such as Sevin ® brand garden insecticides for help. Tough on beetles, but easy on gardens, Sevin ® Insect Killer Ready to Use kills flea beetles by contact and helps prevent damage to tender seedlings at the first sign of trouble.
Always match your garden edibles to the product label and follow guidelines for intervals between treatment and harvest. For example, treat tomatoes and lettuces with Sevin ® Insect Killer Ready to Use right up to one day before you pick them. For sweet corn, allow three days between application and enjoying your ears. For larger areas, Sevin ® Insect Killer Concentrate and Sevin ® Insect Killer Ready to Spray provide the same highly effective control for these pests and hundreds more.
Prevent Future Infestation
As soon as flea beetles arrive in the garden, damage starts. These preventative measures can help avert an attack and lessen your risk:
- Manage the garden environment with good sanitation. Clear leaves and crop debris at the end of the gardening season, so that adult flea beetles have no protection from the cold.
- Till garden soil just after the first frost to uncover any beetles that have gone underground for the winter and leave them exposed.
- Plant an early season «trap crop,» such as radish or mustard seeds, to attract flea beetles when they first emerge from the soil. Then, spray with liquid Sevin ® Insect Killer insecticides and follow label guidelines for how often to treat. With bell peppers or tender greens, you can spray as often as once per week.
- Wait until seedlings have more than three leaves before transplanting into the garden. 2 Larger plants can survive more flea beetle damage than smaller seedlings.
The sudden arrival of flea beetles can stress plants and gardeners, but taking steps to control these pests with a hand from the GardenTech ® family of brands helps guarantee a good start to the growing season and gardening enjoyment.
Time it takes to control flea beetles:
For the average garden, 15 minutes per treatment until beetles are gone.
How hard you’ll work on a scale of 1 to 4:
2 – Easy Does It
Duration of Treatment:
This varies greatly, depending how severe the infestation is and the number of flea beetle generations involved. Used properly, liquid Sevin ® Insect Killer pesticides kill flea beetles by contact and keep helping to protect your garden for up to three months.
Always read product labels thoroughly and follow instructions, including guidelines for pre-harvest intervals (PHI) and application frequency.
Sevin is a registered trademark of Tessenderlo Kerley, Inc.
GardenTech is a registered trademark of Gulfstream Home and Garden, Inc.
1. G.R. Nielsen, «Flea Beetles,» University of Vermont Extension, January 1997.
2. V. Grubinger, «Flea Beetles Management,» The University of Vermont, November 2003.
3. S. Burkness and J. Hahn, «Flea Beetles in Home Gardens,» University of Minnesota Extension, 2007.
Tomato Diseases: How To Fight Anthracnose
by Matt Gibson
Finding out that your tomato crops are infected with tomato anthracnose can be incredibly discouraging. You may notice ugly legions and large rotten areas and realize that you have noticed the infection a bit too late in the game to save your plants. Untreated anthracnose can cause a whole lot of damage and destroy an entire crop turning a beautiful looking group of plants into a crop of rotten fruit in just a few short days.
It is extra important when dealing with anthracnose, to catch the infection as early as possible, because like many fungal diseases, anthracnose is tough to treat once the infection has taken hold, but the damage can still be minimized if you catch it early enough. Vigilant scouting is essential, if you want to catch the disease before it’s too late.
Causes And Symptoms of Anthracnose
If the soil that you are growing your tomatoes in has inadequate drainage, you are providing an environment that is more susceptible to the bacteria that is responsible for anthracnose. Colletotrichum bacteria is known to attack the tomato plant’s fruit during every stage in its growth, and it is especially fond of soggy soil. The bacteria can be spread by wind, birds, and insects, which infect the soil with the bacteria, initiating the disease.
Once the anthracnose fungus is present in the soil, it can be splashed onto the plant with irrigation or rain water, or attach itself to the fruit if/when it touches the ground. The roots of the plant can also be attacked, especially in a greenhouse, as the warmer temperatures and aerial watering systems help the fungus stay active in the soil. Any small lesion in the root system, which could easily be caused by garden pests like the flea beetle, provides an easy access point for the disease to enter and begin to colonize within the plant.
If the colonization occurs when the plant has green fruit, you will not be able to see the infection until the fruit starts to ripen. Once the tomatoes start to become ripe, the symptoms of anthracnose start to become more noticeable. Small, slightly sunken, wet-looking spots or abrasions will appear. The lesions quickly get larger and the depressions become more pronounced as the disease progresses. The center of the tomato begins to darken, and you will notice the emergence of many small, fungal structures. A semisoft decay begins to occur as the fungus spreads, eventually leading to large rotten areas. Once the disease has reached this stage, there is no saving the harvest.
Treatment and Control of Anthracnose
Once anthracnose has had a chance to spread and progress, gardeners are left with a big mess to clean up, instead of a big harvest to reap. This can be quite disheartening. The best way to avoid the devastation of your tomato plants, is to prevent anthracnose, and other tomato diseases from occurring in the first place. The best way to keep anthracnose out of your tomato garden, is to practice cultural control methods, which minimize the chances of soil infections such as anthracnose.
Annual crop rotation is one of the best ways to fight soil-borne fungal infections. Make certain that no non-solanaceous plants like peppers, soybeans, and potatoes were planted in the soil that you are about to grow your tomatoes in within the past year. Continue to rotate out where you grow your non-solanaceous plants, putting two to three years (if possible) between each crop.
Using only certified, disease-free seeds will really help avoid fungal issues as well. If disease-free seeds are not available, soak the seeds in hot water for 25 minutes before planting to kill any bacteria that might be growing or living inside the seeds you are about to sow. Oftentimes, it is through the seeds, or transplants themselves, that the fungal spores of anthracnose and other diseases are able to enter your garden.
Another good cultural control practice is to lay out a thick layer of mulch around the base of each tomato plant. Mulching will help direct the water into the soil and away from the above ground parts of the tomato plant. Mulch will also act as a barrier between the plant and the soil itself, which will cut down on the possibility of spores splashing onto the plant due to rain or irrigation.
Once an infection has been noticed, it is of vital importance to remove all infected fruit from the vine and discard it properly. Plants that survive the infection can be treated with fungicide sprays that can be highly effective. The best fungicides on the market for tomato diseases contain potassium bicarbonate, which is safe to use on food products, and is considered safe by the FDA.
The most commonly used fungicide for anthracnose is sodium bicarbonate, or baking soda. This organic treatment can be used for both prevention and treatment. If your plants are showing signs of powdery mildew, hit them with a blast from the water hose on the infected areas to dislodge and knock loose as many mold spores as possible.
Fungicides used to fight septoria leaf blight will also work for protecting fruit against anthracnose. Also, fungicides that are copper based have been successful in treating anthracnose.
Common Questions and Answers About Anthracnose
Can anthracnose kill trees?
As a rule, anthracnose does not kill trees. However, repeated infections with anthracnose can make trees weaker and more likely to die as a result of other issues. Anthracnose may cause leaf drop, but those leaves will be replaced with new growth once the weather warms up. Cankers may also develop as a result of anthracnose, which can kill individual branches due to girdling. Cankers may also result in the death of buds and twigs. During the tree’s dormancy, anthracnose can kill its bark and cambial tissue. (Cambial tissue, or cambium, is the layer between the bark and wood that produces secondary growth of stems and roots.)
Can you eat tomatoes with anthracnose?
As long as you cut out the infected area of the tomato, it is safe to eat tomatoes infected with anthracnose. Be sure to throw away the infected area, as it contains the spores that cause anthracnose and can spread the disease.
Does anthracnose stay in soil?
Anthracnose is a soilborne disease, and the spores that cause anthracnose live in infected soil. The fungi that cause anthracnose also survive the winter on infected plant debris on the ground, such as infected buds, leaves, twigs, and fruiting structures. In infected trees, the anthracnose spores overwinter in dead twigs and the margins of its cankers. Anthracnose spores can live in soil for three to nine months, even without an infected plant nearby. In the soil, spores travel and spread through the movement of water, such as morning dew, runoff, irrigation, or rainfall.
That’s why it’s important to clean up and dispose of plant debris near affected plants as one of the main ways to fight anthracnose. Do not discard infected debris or soil in your compost pile; it should be dried and burned. Your compost may not reach temperatures high enough to kill the anthracnose spores, and you’ll risk spreading the disease further. It’s also important to wash your clothing, garden tools, and gardening gloves, as anthracnose can live for up to six weeks on these items.
Does neem oil kill anthracnose?
Yes, neem oil is a common remedy gardeners use to fight against anthracnose. You can make a homemade neem oil spray treatment by mixing four or five drops of dish soap and one teaspoon of neem oil into a liter of warm water.
How do you treat anthracnose on tomatoes?
Treating anthracnose is a multi-step process. First, remove any infected plants from your garden, then destroy them. Do not add them to your compost heap, as you risk reinfecting plants when the compost is used. Also bag and remove any plant debris or fallen leaves underneath or surrounding the infected plants, then dry and burn this material. Then apply a fungicide of your choice. Sulfur dust fungicide and liquid copper fungicide are both good choices.
Do not replace plants in the spots where infected plants were removed, as anthracnose may still be lurking in the soil. Mulch the surface of the soil around your remaining plants to provide a barrier between any spores that may be in the soil and your plants. This barrier is meant to prevent anthracnose spores from spreading from soil to plants via splashing rainfall or irrigation. Be careful not to let mulch touch your plants; leave a space between the stem or trunk of each plant and the mulch you lay down.
Cultural controls and preventive measures should be called on to make sure anthracnose does not return after it’s been removed from the garden. Water plants in the morning to give them plenty of time to dry out before the cooler temperatures at night. Make sure plants are buried to the appropriate depth so leaves are not directly touching the soil. You can also utilize staking [https://www.gardeningchannel.com/staking-your-garden-plants-guide/] or place cages around your plants to prevent them from coming in contact with potentially infected soil. After each time you work in your garden, clean and sterilize tools, equipment, gardening gloves, and the clothes you wore to work to prevent spreading anthracnose. Anthracnose spores can live on garden tools or clothing for up to six weeks.
Is anthracnose harmful to humans?
Anthracnose cannot infect humans or cause symptoms in humans.
What are the symptoms of anthracnose?
Symptoms of anthracnose begin with small discolored spots on leaves, which may be yellow, brown, dark brown, or black. These spots spread and expand until they can eventually cover an entire area, with the color darkening as time goes on. Cankers may appear on stems or on the stalks that join leaves to stems (called petioles), with leaves dropping and fruit rotting where cankers appear. Roots may also show rotting, which is called black dot root rot. Infected fruit can be identified by waterlogged circular spots that create sunken areas up to half an inch across. Eventually, these spots turn black in the center and release masses of spores, which range in color from pink to orange and have a texture like gelatin.
What causes anthracnose?
Anthracnose is a fruit rot disease caused by various species of fungi including Apiognomonia errabunda, A. veneta, Colletotrichum gloeosporioides, Discula fraxinea, the Glomerella species, the Gnomonia species, some Marssonina species, and Stegophora ulmea. The spores live on infected plants, plant debris on the ground, and in soil, and it can also be seedborne. Water helps spread the spores via irrigation, morning dew, rainfall, and runoff. Anthracnose is also spread through wind, insects, and gardening tools, equipment, and clothing exposed to the spores. It’s most likely during periods of cool, wet weather and high humidity.
There are also factors that make anthracnose infection more likely or help it along, which gardeners can address via cultural controls and preventive measures. Ensure plenty of air circulation between plants by providing proper spacing and staking tall plants. Add a layer of mulch to provide a barrier between spores that may be lurking in the soil and plants, being careful not to let the mulch touch plants directly. Avoid overhead irrigation systems or watering from overhead, as the water that splashes onto foliage can help spread anthracnose. Instead, use drip irrigation or water the base of plants.
Make sure that soil is well-draining, and amend it with compost to give plants the nutrition they need to grow strong and healthy and fight disease. Avoid allowing fruit to touch the soil. Rotate plants every two or three years. Pick fruit as soon as it ripens to lessen the chance of anthracnose developing. Do not save seeds from your plants in a season when you’ve struggled with anthracnose. Try not to work in the garden when the fields are wet, and always disinfect gardening tools and equipment as well as clothing and gloves when your work is complete. Gardeners can also opt for plant varieties that are resistant to anthracnose.
What does anthracnose affect?
Anthracnose infects crops such as bananas, cereal, corn, cotton, curcubits, mango, onions, peppers, sorghum, and tomatoes. Anthracnose can also infect shade trees, with ash, oak, maple, white oak, walnut, and sycamore being particularly susceptible, along with grasses and annuals.
What does anthracnose look like?
Anthracnose starts out as small discolored lesions on foliage, ranging in color from yellow to brown, dark brown, and black. The spots expand as the disease spreads to eventually cover whole areas of the plant, turning darker as they mature. Anthracnose also causes cankers on stems or leaf stalks that can cause rotting fruit or result in leaf drop. Roots may show black dot root rot. Fruit infected with anthracnose exhibits watery circular sunken areas up to half an inch wide that eventually turn black in the middle and release fungal spores, which are gelatinous and range in color from orange to pink.
If you have spotted tomato anthracnose in your garden, send us pictures!
Want to learn more about Anthracnose on tomatoes?
Oklahoma State University covers Anthracnose of Tomato
Cornell University covers Tomato Anthracnose