Loaded with many health benefits, having spinach in your garden is worth it.
But, it is worrisome to watch white spots on spinach leaves. Those tiny dots on dark green leaves of spinach may raise many questions.
Are white spots on spinach leaves safe to eat?
To determine, you must first diagnose the cause of white little spheres on this green leafy vegetable plant.
Rebecca Sideman (Horticulture State Specialist) states that trichomes are white spots or fuzz on young spinach plant leaves. They are nothing but a part of the leaf, which can be seen in many plant leaves, including spinach. (Source)
Spinach trichomes are tiny hair-like structures that have some purpose. However, in the case of spinach, it isn’t studied widely. They are commonly seen in younger leaves and are not at all harmful.
On the other side, white spots or white rust can also caused by fungus.
Albugo Occidentalis is the fungus responsible for the development of white rust on spinach leaves.
This parasite attacks the spinach plant and starts feeding on it. It draws its nutritional requirements from the plant, thereby obstructing its growth.
You need to differentiate between trichomes and fungal infections.
Also Read: Why Spinach Leaves Turning Yellow or White
What Causes White Spots on Spinach Leaves?
The white spots or rust primarily appear on spinach plants during cold weather.
Spinach is a tropical plant and grows better in warmer weather.
Cold and moist weather allows parasites, such as Albugo Occidentalis, to reproduce at a quick pace and attack plants. Continuous rain, replanting, and over-irrigation are some of the causes of white spots on the spinach leaves.
Let us look at the causes of white spots on spinach leaves in detail.
1. Cold and moist weather conditions
As we have already discussed, moist weather favors the parasites, and they reproduce quickly in such conditions. As a result, the chances of an attack on spinach increase manifolds.
The Albugo Occidentalis reproduces through zoospores. The zoospores require 55-62F temperature to attack and infect a plant.
Thus, cold weather is most likely to bring infections to your spinach plant.
These attacks are more common during the spring and winter seasons. As in these seasons, the humidity level in the air is high, and the temperature is constantly low. Frosty mornings give an added advantage to the fungal parasites.
In the initial stages, the attack by parasites causes chlorosis, a situation in which the plant cannot produce sufficient chlorophyll to meet its requirements.
This turns the leaves yellow, and the continuous cold weather further allows the parasite to germinate and form white spots.
Eventually, the spots cover all of the leaves and hinder the plant’s growth. The fungus could potentially kill the plant if proper prevention measures are not taken.
Different fungi can cause white spots on spinach leaves; some of them are listed below:
- Cercospora leaf spot appear as small white patches on your spinach leaves, but as the fungi mature white spot turns grey.
- Downy mildew is one of the common fungal diseases that cause grey or brown spots on leaves.
- Anthracnose causes tan lesions on spinach leaves.
- White blisters can be seen on spinach leaves in white rust fungal infection.
You can use store-available fungicides to treat white spots on spinach leaves that are caused by fungal infestation.
How to Determine the Cause of White Spots on Spinach Leaves?
Pro Tip: if you can easily rub off the white spots, they are common trichomes that are safe to eat.
2. Replanting Similar Plants
Planting similar plants in the same soil mixture can lead to the reoccurrence of similar infections.
Most of the pathogens that affect spinach are soil-borne; therefore, planting similar species of plant increases the chances of infection.
The parasite that causes white spots or white rust on spinach plants is present in the soil and affects the leaves at the base of the plant in the first place. Most gardeners believe that if they remove the infected plant and replant a fresh spinach in its place, the freshly grown plant will be free from infection.
This is a mistake, as the parasite is still present in the soil, and replanting the same plant will also invite infection to the freshly grown plant.
Uprooting an infected plant and replacing it with the same plant is not a solution to preventing white spots from occurring; rather, it worsens the situation.
Unless the soil is mixed and replaced completely, and proper hygiene of the plant is maintained, it is impossible to eliminate white spots/rust.
Fungal parasites thrive in damp places. They travel quickly in water and attack plants at a faster speed. It is, therefore, crucial that you do not overwater your plant, as this does not help your plant’s growth in any way.
Rather, it invites parasites, which none of the gardeners want for their plants.
Spinach plants require substantial water to grow, but over-watering should be avoided.
You should understand the requirements of your plant and water it only when needed.
As gardeners, we all want to provide suitable growing conditions for our plants, but in doing so, we should remember that anything in excess does more damage than any good to our plants.
So, to avoid overwatering your plants, you should check the soil’s moisture level before adding water to it.
If the soil is damp, skip watering it as it can damage your crop. Only water the spinach when the moisture level in the soil is low, and you feel your plant needs water.
Also Read: How to Grow Malabar Spinach Plant in Pots?
How to Treat White Spots on Spinach Leaves?
You can treat white spots on leaves by using fungicides. What is more important is to prevent them.
Maintaining proper hygiene, using scientific irrigation techniques, and crop rotation are a few techniques that can prevent white spots or white rust from occurring on spinach.
Along with these methods, there are also other ways of preventing white spots from forming on your spinach.
Read on to learn how to protect your plant from these parasites.
Fungicides are an effective way of controlling the fungi in your garden. Regularly spray fungicides in your garden to prevent the parasites from attacking your plant.
Consult an expert and use the best fungicide available in the market. The major ones in use against the Albugo occidentalis are pyraclostrobin and azoxystrobin.
Use Copper Compounds
Gardeners should use liquid compounds of copper to prevent or treat white spots.
These copper compounds are proven effective against the parasites that cause white rust, and therefore, every gardener must use them against pathogens that can harm their plants.
As we have already discussed, the damage is caused by overwatering your plants. To prevent such damage from happening, one should not overwater the plants.
Continuous damp soil, wet leaves, and an overall humid environment are extremely favorable to parasites.
If these conditions persist, your harvest will be destroyed by the attacks from pathogens.
Therefore, add water to your plants only when necessary, and do not sprinkle water on spinach leaves. Rather, just water the roots.
Sulfur is effective against the parasite that causes white rust on spinach, and therefore, when you notice the presence of white spots on your spinach leaves, you should spray sulfur to cure them.
It is advisable that while Springs Alpha, you take necessary precautions like covering your eyes and mouth.
Although sulfur is not very harmful to the skin and eyes, spraying sulfur can irritate some people.
Accordingly, always cover your eyes and protect your mouth and skin if you’re using sulfur.
Continuous planting of similar species also increases the chances of similar infections in the freshly grown plants.
Therefore, gardeners should use crop rotation as a way of bringing back the nutrients in the soil so that it could help your plant growth.
Do not grow similar plants repeatedly as they rip off the soil from its essential nutrients and increase the chances of damage to your plant.
Proper plant hygiene is necessary if you do not want parasite attacks on your plant.
Regularly cut out the weeds in your garden, spray pesticides to free your garden from the presence of pests, and clean the leaves of the plant from dust.
If you follow these measures regularly, your spinach plant parasites will not attack you, and you can enjoy a healthy harvest.
However, it is important to note that you should spray sulfur or fungicides only when you notice the presence of white spots in the first place.
Also, make sure that you do not overpay your plants with chemicals. Otherwise, it could impact your plants negatively.
Irrigate the soil properly and check the moisture level of the soil before watering to prevent the occurrence of parasites in your garden.
Also Read: How to Grow Parsley From Seeds Indoors?
Is It Safe to Eat Spinach with White Spots?
- White spots are indicative of the fact that parasites or fungi have attacked your plant.
- Washing the leaves might make the spots less visible, but it does not change the fact that the spinach leaves have been attacked by parasites still present on the leaves.
- Such plants should not be consumed in any situation as they are infected by parasites, and consuming them, raw or after steaming, can also infect you and harm your health.
- Throw the infected spinach right away, and do not consume it. The parasite has attacked the plant and fed itself on the nutrients present in the spinach plant. What you have now is just an infected plant with no nutritional value. Plus, there are parasites present in it. So, you should never consume infected plants.
Other Spinach Related articles:
- How Long Does it Take to Grow Spinach?
- Will Spinach Grow Back After Cutting?
- Why are Spinach Leaves Turning Yellow or White?
- What Vegetables to Grow All Year Round?
Spinach plants have health benefits and should be included in your diet. You can eat spinach leaves with white spots if they are just trichomes.
But, if you notice white rust or downy mildew disease, you should destroy the affected leaf to stop further spread.
While growing spinach, use the necessary preventive measures to avoid white spots or rust.