Eliminate Microgreens Containing Mold?
“Could that possibly be mold growing on my microgreens? Do I need to get rid of them completely?”
Thankfully, the answer is “No” virtually all of the time. The white fuzzy stuff that is often found surrounding microgreens is not mold but rather root hairs 85 percent of the time.
Root hairs are typically white in color and have a fuzzy texture. They emerge from the root radicle and are on the lookout for water and nutrients. Both can be true in some situations. Both the seed and the soil are covered in a fuzzy mass of white mold that is now expanding.
The root radicle is coated with another white mass that is made up of small individual root hairs as it searches for soil.
Is That Mold on the Microgreens or Root Hairs from the Microgreens?
We are here to alleviate some of your concerns and save you some time straight away. The majority of the time, the white hairs that appear fuzzy are actually root hairs. Particularly in the event that you intend to cultivate more typical microgreens such as broccoli, kale, cabbage, or radishes.
Mold often does not grow on seeds with such a smooth and tough hull as those. There is always the possibility of an exception, but in most cases, the problem is not the seed. In the following sections of the text, we will go into further detail on these issues.
Mold can grow on microgreens seeds, so keep an eye out for them. Mold is more likely to grow on seeds that have one or more of the following characteristics: a softer shell, a rough surface, or have been soaked in water before being planted.
Microgreen seeds such as sunflowers, peas, and cilantro are included in this category. We also believe that spores clinging to the porous and rough surface of the seeds of Swiss chard and beets are the source of the damping-off disease that is affecting your crops.
It’s possible That The “Mold” you see on microgreens is actually root hairs. The vast majority are root hairs, which is a natural occurrence for the vast majority of microgreens. We are aware of the panic that has been caused. We are all quite eager to see what has grown over the blackout time, and when we finally remove the cover, we hope to find that our plants have developed magnificently.
And what exactly do we see here? It’s possible that the fact that we know we’ve poured water, placed the tray in a dark spot, and laid weight on top of the soil to trap in the moisture has led us to anticipate mold growth.
It’s also possible that we’ve never noticed root hairs since we’ve always covered our seeds with dirt in the garden, which is the more likely explanation. Root hairs are the most likely explanation for what you are seeing.
Root hairs may be identified by their white filaments that grow from the seed radicle. Even though the fuzzy white spread on your tray seems more like mold on microgreens, it is actually just fine root hairs that are, in some cases, spreading over surrounding seeds. A little bit further into this content, we will demonstrate how to distinguish mold root hairs from other types of mold.
One further way to recognize that these are root hairs. Spray some water over them. They shouldn’t be sprayed under a great deal of pressure. Only mist the objects that are white and fluffy. In the event that they are root hairs, they will fall out. They don’t adhere to the radicle, but you won’t be able to see them any way.
On the other hand, mold will just spread out and cover everything. After the misting, you will still be able to see it.
After a few more days, your root hairs will definitely disappear. As the root continues to penetrate deeper into the soil, the root hairs will fall off in a few of days. Mold won’t kill it.
When grown on mats, the root hairs of microgreens will be visible for a longer amount of time than when grown on other media. There is never a situation in which the radicles are dragged down to the same extent as with dirt. When we use matting, we believe that this results in a greater amount of accessible moisture at the surface.
Therefore, the root hairs will continue to exist since they are able to fulfill their purpose in their current position.
Therefore, your white fuzzy mass does not resemble your root hairs in any way. If this is the case, then it most likely is mold. There are occasions when mold on microgreens is very noticeable.
It is possible that the problem was caused by the insufficient decomposition of the organic matter that took place before the soil was bagged and sent out for delivery. Compost is an essential component of every high-quality potting soil mix. In addition, once the components of the potting mix are mixed together, they will begin the composting process once more.
The microorganisms will devour the nitrogen, which will result in the production of heat whenever nitrogen supplies are combined with carbon sources. It is possible for the fresh potting mix to generate heat if it is bagged before the composting has, for lack of a better description, equalized.
Warm and moist conditions increase the likelihood of mold growth on microgreens. There is a possibility that the increased temperature of the working potting mix will not be sufficient to stimulate the formation of mold. However, when we place microgreens in a blackout period and cover them completely, we have effectively produced an oven.
Mold may easily grow in this environment since the composting process generates additional heat, and the lid ensures that there is a consistent amount of moisture present.
If the temperature in the room is excessively high, especially during the summer months in a home that does not have air conditioning, you will also see a pattern like this. Or even when utilizing heating pads throughout the colder months of the year. The microgreens that are developing on the outside corners of the tray, where the temperature was lower, will flourish wonderfully.
However, in the dead middle of the tray, there will be concerns with germination and damping-off disease. At the moment, we are focusing on refining the usage of heating mats in conjunction with trays that are totally covered in microgreens.
It is thus recommended that you do not use a solid cover on the top during the warm months or if you are using heating mats. Instead, you should utilize a plant tray that is ridged, as this will allow both heat and moisture to dissipate from the center of the tray.
Mold on the Seeds and Stems of the Microgreens
The radicle, which is the first component of the seed to develop roots, will invariably have root hairs on it. Yes, it is possible for the root hairs of neighboring seeds to grow over other seeds at times. Mold is present, however, when fuzzy white growth may be seen developing on either the seed husk itself or on the stem of the plant.
Microgreens do not have the ability to produce root hairs on their stems. Mold of this type is typically seen on microgreens grown inside of domes, but it is extremely unusual to find it on microgreens cultivated using the weighted approach.
Mold on microgreen seeds has the potential to spread to the surrounding soil as well.
The amount of water that is being applied is excessive, and as I was planting it, the tray became completely saturated with water.
The liquid rises up through the soil and collects on the cover, which causes the top layer of the soil to become saturated. Mold is commonly the consequence of using seeds with a tough husked, such as borage.
How to Prevent Mold from Forming on Microgreens and Where to Buy It
Mold spores may be found almost anywhere, and we are perpetually engulfed in a spore storm.
As a result, the most effective method for preventing the growth of mold is to eliminate the conditions that make it possible for it to flourish.
Here are five different ways to cut down on mold growth: Let’s start preventing mold before we even sow microgreen seeds.
Put Your Focus On The Ground
The fact that soil is typically packaged in plastic bags has both positive and negative aspects.
It is essential to use the plastic bags in order to protect the soil from the moisture in the air. Additionally, they are more long-lasting than paper bags or paper bags coated with plastic.
Commercial soil bags do, in fact, have holes in them. These holes serve to maintain the moisture content of the bag (albeit they are harmful to fungus gnats and mold spores), and they also prevent the bag from bursting if it is dropped or if anything is put on it.
On the other hand, plastic does act as a barrier. When the bag’s temperature changes from lower to warmer, whatever moisture that was already present in the soil will condense and become more concentrated.
Always be sure to open a bag of soil as soon as you receive it into your house or as soon as it is delivered to you.
The next step is to get a storage container, after which you will move the soil into the container so that there is increased circulation of air. Your local DYI store will have black bags. Find the ones that are strong, do not bend or fold, can be stacked, and come in a variety of sizes to choose from.
A bag of dirt of 2 cubic feet may be stored in containers with 17 gallons capacity. If you are purchasing smaller bags of 8 quarts of potting mix, you need at the very least unzip the bag so that excess moisture may escape. Both should preferably be placed inside of a compact container that has some headroom for storing purposes. It is acceptable even if it does get dry. It will become moist again, particularly coconut coir.
Wash And Sanitize The Trays
After each use, the trays used for growing microgreens have to be cleaned and disinfected. It’s possible that mold grew on the planting material during the previous batch and then spread to the trays via airborne spores.
Or the soil itself may have spores that were not successful in growing in the prior batch of microgreens. That doesn’t rule out the possibility of their doing it again in the future.
How to Properly Sanitize Platters. There are a lot of different approaches to take here.
It is possible to rinse out and then place in the dishwasher more compact trays such as the 1010 planting and watering trays, upper rack is recommended. Or using the procedures listed here. Bleach, Vinegar, Hydrogen Peroxide – Soak or Spray the Area.
After removing any residual dirt from the trays, either soak them in one of these solutions or spray them with one of them. They will eliminate or significantly cut down on the amount of mold spores that may be present on the trays.
Use approximately one tablespoon of bleach for every eight ounces of water.
When utilizing vinegar, the appropriate amount to utilize is two teaspoons for every 16 ounces of water.
When it comes to sanitizing trays, we believe that it is fine to use the brown bottle of 3 percent hydrogen peroxide that is sold in pharmacies. When the spray dries, the stabilizer will be destroyed, and it will no longer be available for absorption by the roots in the future.
However, you should only apply hydrogen peroxide that is approved for food use on living microgreens or soil.
Mold can frequently be seen to be growing on microgreen seeds. As was previously stated, seeds of sunflower, peas, cilantro, borage, and Swiss chard that have a rough and uneven husk are particularly prone to transporting mold spores.
How to Properly Clean Seeds
Before they are planted, all of the different kinds of seeds can be sterilized. But it’s a hassle to spread out little wet seeds, and they typically don’t provide much of a mold danger since it’s difficult for the mold spore to cling to the smooth spherical seed. This can be a problem.
However, the mold spore count can be reduced in the other items described above by soaking them for ten to fifteen minutes in a solution of food-grade hydrogen peroxide that has a concentration of three percent.
After that, you should wash the seeds with clean water. If you feel that further practice is required, you are free to carry out this procedure many times. For example, if you experienced problems with mold when you bought this batch of seed in the past.
We always make an effort to grow a batch of seeds on our own first before we sterilize them. In the event that the planting does not result in the development of mold, we are not going to sterilize that lot until we have issues.
Make Use of Soil That Has A Decent Drainage System
It is beneficial to drainage for your soil to have components such as perlite, old forest products, volcanic rock, and similar components. Particles and materials with irregular shapes and varying degrees of porosity can assist direct water away from the plants and down and away from the soil.
Utilizing a soil medium that has particles that are uniform in size, shape, and porosity will allow water to be retained.
No need to remind you to use trays with holes as planting trays. You already know how to do that, don’t you?
Pre-Wetting The Soil Is Not Recommended
When it comes to planting seeds, we strongly recommend that you do not overwater the soil.
When sowing microgreen seeds, we just water the top one third of the soil profile. There is no requirement for the soil in the tray to be completely saturated with water before sowing seeds. During the time of germination, it is sufficient to just moisten the top third of the soil.
Saturating the entire soil profile leads to heating up the inside of the soil and causes it to become saturated. Hence providing the ideal environment for the growth of mold.
Don’t Plant Too Many Seeds or Clump Them Together
The seeding density of Home Microgreens has been called into doubt by a lot of individuals. It is commonly believed that we seed our trays too lightly.
This is not the situation at all. We put all of our suggestions for seeding density through rigorous testing, and we arrive at the final rate after considering a wide range of characteristics that are relevant to producing microgreens at home.
The quantity of seed that other people advised was one of the primary motivating factors that led me to establish Home Microgreens.
The interior of the tray remained consistently damp or wet, the plants were overcrowded, and the microgreens consisted almost entirely of stems with very few leaves.
In addition to causing disease problems when the microgreens mature in an environment with reduced ventilation, over-seeding can also lead to problems during the germination process. Mold seems to grow in places where there is a concentration of seeds that have gathered together.
Whether this is due to mass over-seeding of the tray or spots where seeds tend to gather, this can happen. For example, at low spots in the soil or all the way around the trays’ perimeters.
The retention of moisture that occurs when seeds come into touch with one another is exacerbated by the fact that the majority of mold is thought to originate in the seed in the first place. To minimize the risk of mold growth, spread the seed as uniformly as you can.
Choose Smaller Trays Instead of Larger Ones
The use of smaller trays will assist in enhancing the airflow that passes through the microgreens. Mold is more likely to grow in the trays’ center sections. Those plants that are growing on the outside edges benefit from significantly greater ventilation and drier circumstances than those in the center.
Instead of cultivating microgreens in a huge 1020 tray, consider growing them in a few 1010 trays or even smaller trays. Mold growth on microgreens can be prevented by increasing the amount of edge area present in the bulk of the microgreens.
Only the Water at the Bottom
It is essential to maintain a dry environment for microgreens in order to lessen the likelihood of mold growth on them. Overwatering microgreens will only lead to more problems in the long run. Yes, major producers of microgreens do irrigate their plants from above. However, these establishments have a far higher volume of airflow than your home does and considerably more powerful lighting.
In this lesson, we will cover how improving ventilation and lighting may help eliminate mold problems.
After the seeds have germinated, the easiest strategy to prevent mold from spreading or developing is to water the soil only from the bottom, and to do so only when the soil is dry.
Mold thrives in damp soil and may quickly spread across the garden.
Proper Air Circulation
It is best practice to limit the likelihood of mold formation on developing microgreens by ensuring that there is adequate ventilation throughout the crop. Mold may be reduced by growing racks that have USB fans attached to them. You don’t need to have them running constantly, but you should do so when the temperature is high and the relative humidity is high.
Although it might not look like much, they really draw a significant amount of air through the fan given that they are always operating.
Bring Down the Humidity
It would be beneficial to bring the relative humidity in the growth region down to a lower level.
If you want to cultivate a significant amount of microgreens, putting a dehumidifier (one that also boosts airflow) close to where you will be growing them is a smart move. You may also lower the relative humidity by cooling the space, which is another option.
Treatments for Mold that Can Be Found on Microgreens
Even if you notice mold on the microgreens, it is possible that you do not have to give up.
When determining whether or not a tray may be reused, we want you to use your own discretion. Always err on the side of caution while making decisions.
Additionally, wash the microgreens before using them, not before storing them as some people do, but before eating them.
Boost the amount of airflow that is available in the region. You should welcome any movement of air. Although the microgreens shouldn’t appear as though they are being blown around by the wind, it is desirable for them to have some movement in their leaves and stems.
If you have the ability to place them in direct sunshine, beneath lights with a greater lumen output, or even relocate them closer to the lights, you should do so.
Mold on Microgreens and the Treatments Available
You have the option of selecting from at least three different therapies.
We have tried two of them, and they are effective provided that the mold problem is not insurmountable.
Mold may be eradicated by spraying it with a mixture that consists of one tablespoon of a 3 percent solution of food-grade hydrogen peroxide and sixteen ounces of water. There is no discernible odor. It’s possible that you’ll need to spray the mold more than once.
There is no need to be concerned because the hydrogen peroxide will eventually break down into oxygen and water.
You will notice that the mold begins to bubble in the same way that peroxide does when applied to a wound.
Because it is stabilized to extend its shelf life, hydrogen peroxide sold in pharmacies is not something you should use.
Dilute 5 percent vinegar, the sort that is offered in grocery shops for the purpose of using it in cooking, at the rate of 1 tablespoon every 16 ounce bottle of spray vinegar.
The dilution should be sprayed onto the mold. Again, it’s possible that more than one misting will be necessary.
It will smell, well, like vinegar. It is also possible that it will attract fruit flies.
Either cider vinegar or white distilled vinegar can be used. Both of these options include additives.
Extract from Grapefruit Seeds
Mix one teaspoon of the extract into a volume of water equal to eight ounces. The mold was eliminated with just a single treatment. The extract of grapefruit seed is the one that we prefer to use the most. It worked very immediately.
Mold on microgreens should be evaluated according to your own criteria. I cannot be held responsible for any decision you make on whether or not you should throw away a tray of microgreens that has mold growing on it. Root hairs are what you see the majority of the time, especially shortly after the blackout, and there is no need to be concerned about them.
However, if you are growing one of the microgreens that has a tough husked seed, you need to look at it very carefully. If it is mold, you will need to assess how widespread it is before deciding whether or not to cure it and whether or not to throw away the tray.
Spray it once with any one of the treatments described above, then move the tray into direct sunshine or bring it closer to the lights, and see how the surface of the tray appears the following day.
We really hope that this post will be of use to you and answer some issues that you may have. In such case, you can either reach out to us using the contact page or share your experiences with us by using the comment box below.