Strawberry diseases can affect the fruit, flowers, leaves, roots, and crowns of strawberry plants, and sometimes cause the collapse of the whole plant. While many of the problems caused by bacteria, fungi, molds, and viruses can be treated when symptoms are observed, some of the most serious strawberry plant diseases cannot be treated after the plants are in the ground. But home growers and organic growers will find many organic options that reduce strawberry diseases, even if they don’t eliminate them, in the A to Z listing below.[feast_advanced_jump_to]
Angular leaf spot first appears as water-soaked lesions on the undersides of leaves and calyxes around the fruit. As the bacterial ooze dries, the next thing you will see is a white powder, followed by purple or red discoloration of the leaf at an angle from the stem to which it is attached. There will be yellowing (chlorosis) around the damaged area of the leaf.
Sometimes this infection with Xanthomonas fragariae bacteria can cause the entire plant to die suddenly, but this is rare. This condition usually doesn’t have a major impact on fruit production by itself, but it can be one among many factors that keep you from getting a good crop. Commercial growers who ship their strawberries across state lines will find their products under quarantine if inspectors find angular leaf spot, so they have to keep this problem under control.
Plant sprays containing copper control angular leaf spots in young plants. An antibiotic for plants called validamycin can control the problem in mature plants. But if you are raising strawberries for home consumption, the most practical approach is soil management.
The bacterium that causes angular leaf spot can only survive on plant matter. If cannot grow on vermiculite or rock used in hydroponic growing, it won’t survive the winter if strawberry plants and their roots are removed from the ground or their growing containers.
Anthracnose is a fungal infection that can attack the crown, stems, leaves, and fruit of strawberry plants. You can recognize anthracnose by the orange ooze of spores it forms on the parts of the plant it kills. These spores are spread by overhead splashing water. If you don’t have any rain and you don’t do any overhead watering after the fruit has set, you can at least save your crop, although plants may be damaged.
This fungus can survive in the ground for up to nine months after the strawberry plant on which was growing dies. It’s important not to leave infected plants in the ground or to turn them under after they die. It’s OK to compost anthracnose-infected strawberry plants if your compost pile heats up enough to kill pathogens.
Preventing the spread of anthracnose begins with your selection of the strawberry plants you put out. Don’t buy plants that were grown in the ground or irrigated with overhead sprinklers. You can kill any anthracnose that transplants may have acquired in the nursery by immersing the plants in hot water as soon as you get them home, but this method only works if you have a thermometer and you keep track of time.
First, it is important to soak your transplants in a warm water bath, 85 to 86 degrees Fahrenheit (about 30 degrees Celsius) for 30 minutes so they won’t be shocked when you put them in hot water. Then your strawberry transplants need to be immersed in water heated to 113 to 115 degrees Fahrenheit (45-46 degrees Celsius), no hotter and no colder, for 10 minutes, no less and no longer. Leaving the plants in their hot water bath too long may damage them, and not heating the water hot enough will not kill the fungus. Finally, your plants need to be allowed to cool off at room temperature for half an hour before you transplant them.
Alternatively, you could dip transplants into a mixture of the fungicides Abound (azoxystrobin) or Switch (cyprodinil + fludioxonil).
It’s possible to pretreat the soil into which you are planting strawberries with the fungicide InLine (1,3-dichloropropene + chloropicrin) to reduce anthracnose problems. If you do this, you should scatter the product over the entire patch rather than concentrating it near plants. Commercial strawberry growers used to fumigate the soil with methyl bromide plus InLine to stop anthracnose, although this chemical combination is decidedly toxic to more than just the fungus.
Another approach to preparing the soil is to “solarize” it by covering it with black plastic the summer before planting. This approach works in hot, sunny summer climates. If you grow strawberries during the summer, you won’t get good results from solarizing during the winter.
Once you get your strawberry plants in the ground, it’s important to avoid overhead watering that causes splashing. Drip irrigation or micro-sprinkler systems are preferable.
There are no “organic” fungicides that kill anthracnose, but you may be able to reduce the problem by choosing your location for planting strawberries carefully. One of the ways anthracnose is spread to strawberries from other plants that harbor the disease but are not damaged by it. Tomatoes, zinnias, peppers, celery, delphiniums, and vetch planted near your strawberry plant can keep it infected with anthracnose. Close proximity to almond trees and pines can also be a problem.
Strawberries are a beloved fruit that many people grow in their home gardens. However it’s not uncommon for strawberry plants to end up with some fungal freeloaders – mushrooms sprouting up from the soil. While mushrooms among the strawberries may look strange are they actually something to worry about?
What Types of Mushrooms Grow in Strawberry Plants?
There are a few main species of mushrooms that tend to pop up in strawberry patches:
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Inky caps – These mushrooms go by names like coprinus and shaggy mane. They start out bell-shaped with a distinct cap, then turn to black “ink” and seem to melt into the ground as they mature. They prefer disturbed ground and composting vegetation.
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Fairy ring mushrooms – Mushrooms like agaricus and marasmius form mushroom “fairy rings” – circular patterns growing outwards in the dirt. They indicate rich organic matter in the soil.
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Puffballs – Roundish mushrooms like lycoperdon and calvatia grow on the ground among plants. When stepped on or poked, they release a “puff” of spores.
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Coral fungi – Unusual branch- or fan-shaped mushrooms like clavarias can crop up, They resemble sea coral with their eccentric shapes,
Are Mushrooms Harmful to Strawberry Plants?
Mushrooms themselves do not damage or infect living strawberry plants. They are the fruiting bodies of fungi whose threadlike mycelium lives in the soil. The mushrooms serve to distribute the fungus’s spores to expand its network.
Most mushroom species found in gardens are saprotrophic – they feed on dead and decaying organic matter like fallen leaves and dead roots. Their role is to break down this material and release nutrients back into the soil.
A few mushroom types are mycorrhizal symbionts. They form cooperative relationships with plant roots, exchanging nutrients for sugars. Plants like strawberries often depend on these beneficial fungal partners to thrive.
The mushrooms are temporary seasonal structures. They do not steal nutrients away from the strawberry plants or competitively exclude them. In fact, their presence often signifies healthy, fertile soil.
When Are Mushrooms Problematic for Strawberries?
Mushrooms themselves are harmless. However, some may potentially signal underlying issues that could cause trouble:
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Excess moisture – Mushrooms tend to fruit after heavy rains or overwatering. Standing water can lead to root rot in strawberries. Improve drainage if mushrooms constantly appear.
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Undecomposed organic matter – Materials like wood chips or mulch that are slow to break down can spawn mushrooms temporarily. Ensure mulch layers are thin and well-composted.
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Weak plants – Fungi may opportunistically fruit on very stressed, damaged, or dying strawberry plants. Varieties susceptible to disease may also show more mushrooms. Boost plants’ vigor to limit fungal growth.
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Contaminated soil – Certain mushroom species only thrive on polluted or contaminated soils. Identify mushrooms carefully and test soil if they seem indicative of toxins.
Overall, occasional mushrooms in the strawberry patch are no cause for alarm. But if they become excessive or suspect, problems like poor drainage, compaction, or nutritional imbalances may need addressing.
Are Mushrooms Among Strawberries Safe to Eat?
This is the big question – can you still eat strawberries if they’re growing alongside mushrooms?
The short answer is yes, it is completely safe to consume strawberries with mushrooms growing among them.
As explained above, the mushrooms are not pathogenic to the plants. They are simply decomposing organic matter in the environment.
Here are a few tips for safely harvesting and eating strawberries with co-occurring mushrooms:
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Pick ripe, healthy strawberries as usual. Avoid any damaged, diseased, or overripe fruits.
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Carefully check for and remove any visible dirt, debris, or mushroom pieces adhering to the strawberries.
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Wash the strawberries thoroughly under running water before eating or cooking. This further removes potentially clinging spores or soil.
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Remove and discard the green caps and stems. Only eat the sweet red berry portions.
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Refrigerate soon after picking and eat within a few days for best quality and safety.
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Cooking strawberries into jams, baked goods, or other recipes further ensures safety. Heat deactivates any possible contaminants.
As long as basic kitchen hygiene practices are followed, there is no danger in eating strawberries alongside mushroom growth. The fungi pose zero risk of toxic, allergenic, or infectious contamination of the harvested fruits.
Tips for Managing Mushrooms in Strawberry Beds
If mushroom growth seems excessive, here are some tips to restore balance to the strawberry planting:
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Improve drainage – Add organic matter like compost to poorly draining soils. Install drainage ditches or gravel beds if needed.
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Aerate compacted soils – Till or loosen overly dense, compressed soils to allow gas exchange.
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Use raised beds – Planting strawberries in raised mounds improves drainage and reduces fungi.
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Water appropriately – Don’t overwater. Allow the soil surface to partially dry out between waterings.
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Use mulch judiciously – Apply only thin layers of well-rotted compost or grass clippings as mulch.
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Remove debris – Keep dead leaves, fallen fruits, and spent plants cleaned up to limit fungal food sources.
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Let soil rest – Rotating strawberry patches to new ground every 3+ years helps disrupt fungal life cycles.
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Grow resistant varieties – Choose strawberry cultivars bred for disease and pest resistance.
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Improve light exposure – Thin overly crowded berry plants and canopy trees/shrubs to increase sunlight.
With attentive soil and plant health management, mushrooms and strawberries can successfully coexist in the same garden space.
The Takeaway
Mushrooms frequently appear among strawberry plants due to their affinity for moist, organic-rich environments. While they may look out of place, the fungi do not harm the living plants. With proper harvesting and washing precautions, berries growing alongside mushrooms are perfectly safe to eat. A few management tweaks can minimize excessive fungal fruiting if desired. So don’t be alarmed by a mushroom or two cropping up in the strawberry patch!
Leather Rot Causes Brown Spots on Strawberries
Leather rot is a relatively common pathogenic fungus (Phytophthora cactorum) that can affect strawberries in any stage of development. It can infect green strawberries. It can infect ripe strawberries. And, it typically only causes minimal damage to commercial farmers. However, home gardeners can lose many strawberries to the fungus if care isn’t taken to avoid infection.
Infection of healthy fruit and subsequent brown spots on strawberries from leather rot typically happens during periods of wet weather. Rainy April, May, and June weather set the stage for infection. The spores of the fungus stay in the soil and can infect strawberries when there are periods of extended wetness. If water remains in contact with fruit for an hour when the temperature is between 62 and 77 degrees Fahrenheit, infection is likely if spores are present. Brown spots on strawberries will come soon after infection as the pathogenic fungus sets up shop in your fruit.
Brown spots on strawberries are most easily seen on immature fruit. If the fruit is still green or white, the spots will be most visible. Ripe fruit can get leather rot also. However, the brown spots will not usually be as noticeable. Sometimes, the discoloration will even be a purple color or just a darkening of the strawberry in the infected area. Usually, along with discoloration, there will be an odor and unpleasant taste in infected berries.
How to Prevent Brown Spots on Strawberries
Preventing leather rot infections is the key to harvesting healthy strawberries.
- The first and critical step is to pick a location for your strawberry bed that is well-drained. Good soil drainage prevents standing water. The absence of standing water makes difficult for the fungus to remain in contact with strawberries long enough to infect them.
- Use a thick barrier mulch. A good layer of clean straw can prevent the spread of leather rot. Clean straw help reduce or eliminate splash from rain. It can assist in drainage. And, it keeps the strawberries themselves from resting on the soil where the pathogenic fungus lurks.
- Avoid shade. Plant your strawberries in full sun to minimize the conditions favorable to fungal infection.
- Plant the rows parallel to the direction of the prevailing winds. Most locations receive there weather, more or less, from the same general direction. If you plant your strawberry rows with the prevailing wind, the fruit and leaves of your strawberry plants will dry more quickly.
- Avoid excessively dense plantings. Be sure to maintain adequate space between your strawberry plants to facilitate drying. Additionally, inappropriate application of nitrogen fertilizer can cause dense vegetative growth that will shade the berries (see 2. above!) and create an environment conducive to infection.
- Pick fruit early. As soon as the plants dry each day, go picking! Removing the strawberries as soon as possible during the day can reduce infections.
- Watch for and remove fruits with any brown spots on strawberries. It is vital for the health of remaining plants that strawberries with brown spots be removed as quickly as possible from the strawberry patch. If strawberries with leather rot are left in the field, the causal organism will multiply and spread.
- As a last approach, fungicides can be used.
Pay attention to your strawberries! If they get brown spots, cull them as soon as possible. Leather rot can be a pain in the neck. If you set up your strawberry bed in a way that helps the fungus instead of impairing it, remedy as many factors as you can. Good luck!
Bortrytis fruit rot is a problem for strawberry growers all over the world. This ubiquitous fungus can attack fruit before or after harvest, transforming a beautiful red and juicy strawberry into an unappetizing and infectious mass of gray mold in just hours. Bortrytis fruit rot also attacks strawberry flowers. In conditions of relatively low temperatures, between 58 to 72° F (15 to 22° C), and high humidity, up to 80 percent of your crop can be lost to bortrytis fruit rot.
Bortrytis spores land on mature leaves and wait for them to die. As the leaf matures and begins to decay, the fungus produces spores that land in flowers. They may kill the flower outright, or land deep inside stamens where they lie dormant waiting for the fruit to form and start producing sugars. As the strawberry becomes sweeter, the fungi grow. The characteristic gray mold may become noticeable before or after the fruit is harvested.
One way to stop the growth of bortrytis on ripe strawberries is to chill them immediately after harvest. Waiting even an hour can give the fungus a chance to destroy the newly picked fruit. Strawberries need to be chilled to between 32 to 37° F (0 to 3° C) and held at those temperatures until just before they are eaten. If you see a moldy berry in a clamshell or a flat, remove it immediately to prevent contamination of all the other strawberries in the container.
If gray mold is a repeat problem in garden strawberries, try spacing them out so more air can circulate around the leaves and flowers, creating an environment in which mold cannot flourish. Or grow your strawberries in hanging baskets. If you are growing strawberries in a raised bed, plant them along the edges so their runners hang over the edge and get more air and sunshine. Remove “mummy berries” that can spread the fungus to other plants.
If you are growing your strawberries in a greenhouse, turn up the heat two to four times a week so your plants spend the night at about 77° F *(25° C). This will discourage the growth of the fungus. Make sure your fans are on a timer so there is adequate airflow over your crop.
Sometimes it is possible to fight fungi with beneficial bacteria. Sprays of Bacillus subtilis QST 713 (sold under the brand names Cease and Serenade). Streptomyces griseoviridis (sold under the brand name Mycostop), and Streptomyces lydicus WYEC 108 (sold under the brand name Actinovate AG) applied before any signs of Bortrytis infestation will help. So, will sprays of potassium bicarbonate keep the surface of leaves and flowers too alkaline for the growth of the fungus? The bacterial sprays and potassium bicarbonate are non-toxic and may be acceptable for organic certification. (Ask your agricultural extension agent for the exact details of regulations in your state or province.)
Commercial strawberry growers often attempt to control bortrytis gray mold with toxic chemical agents. The problem with trying poison gray mold is that it reproduces so often that mutations occur that it has the ability to resist fungicides. Among the fungicides that are unlikely to be helpful are fenhexamid (sold under the brand name Elevate), pyraclostrobin + boscalid (sold under the brand name Pristine), cyprodinil + fludioxonil (sold under the brand name Switch), and thiophanate-methyl (sold under the brand name Topsin). Your extension agent can help you find fungicides that are still effective against bortrytis gray mold in your area.
What To Do About MUSHROOMS In The Garden?
FAQ
How do I get rid of mushrooms in my strawberries?
Just brush the schrooms away with a hoe or rake. And for goodness sake, put some straw or mulch around the strawberries , don’t want the leaves or the fruit to touch the soil.
Should I remove mushrooms from my garden?
As an FYI- picking them out would do absolutely nothing. The mushrooms we see are just the fruit of the fungus, there is a whole “body” of the fungus beneath the soil. It would be akin to picking your tomatoes and thinking you’ve taken out the whole plant.
Do mushrooms indicate healthy soil?
Yes, mushrooms are often a sign of healthy soil with active microbial life. However, if they’re excessive, it may indicate too much moisture or decaying material.