Tomato Leaves Turning White? What's Happening and How To Fix It.
Leaves Turning White on Tomato Plants?
Hey, tomato gardeners! Have you been noticing that your tomato plants have leaves with white or silver on them? If so, don't worry - it's not a death sentence for your tomato plants. There are several possible reasons why this could be happening and we will discuss those in detail below. It is important to know the cause of the problem so that you can take proper steps to fix it. We also share our favorite tomato plant fertilizer recipe at the end of this blog post if you need a little help keeping your tomato plants healthy and green!
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Why Do Tomato Leaves Turn White
This is a very common tomato plant problem. It can happen for a variety of reasons, so it is important to identify the cause and take steps to correct it in order to fix your tomato plants' leaves turning white issue. Let's go over some possible causes:
Your tomato plant can be getting too much direct sunlight
The tomato plant's sensitive leaves are easily burned by the sun if it gets too much exposure. This is referred to as sunscald and can happen to tomato plants that are in a location where they get full sun throughout the day.
They will start to develop pale yellow or white patches on their leaves, which is not something you want happening with your tomato plant's foliage.
Tomato plants are sensitive to cold temperatures
If conditions are too cold outside of the tomato plant's optimal temperature range, then it will develop white patches on its tomato leaves. The tomato plant's response to the cold temperature is for the tomato leaf cells to close up, this will protect them and keep in heat if they are too far from a warmer area (such as a greenhouse or house).
Leaving it outside unprotected when it reaches these colder temperatures can cause major damage to plants that start with tomato leaves turning white.
Fungal diseases can also cause tomato leaves to turn white
This typically happens when tomato plants have been overwatered and the fungi will start growing on the tomato plant's roots.
Tomato plants can also have nutrient deficiencies or too many nutrients
This can cause tomato leaves to turn white as well. Some common nutrient deficiencies are due to not enough calcium, magnesium, nitrogen, or phosphorus in tomato plants.
The nutrients and minerals tomato plants need can be found in fertilizers formulated for tomato crops or through the use of composts. These nutrients will keep tomato leaves from turning white by maintaining healthy plant growth.
“Sunscald is common when transplanting seedlings .”
How To Fix Tomato Plant Leaves Turning White
Now that we know the possible causes of tomato plant leaves turning white, let's take a look at some possible solutions for each cause.
Solutions to Tomato Sunscald
White leaf color is often a sign of damage from sunlight, which appears as a border on the tomato plant's leaves. Curled leaves and broken foliage may be seen on the tomato plants. Heavy winds in the area can make this condition worse.
What should you do if your tomato plant is affected by sunscald?
If tomato leaves turn white and curl up, it is most likely too late for the plant. Since sunscald is not a tomato plant disease, tomato plants with this condition will not recover.
However, if the entire plant isn't affected, tomato plants can be treated by moving them to a shadier location and you can try removing the damaged tomato leaves.
If tomato plants have sunscald, you can also apply a mulch or straw to the soil around the plant for added insulation and protection from harsh sunlight.
Some tomato growers suggest a tomato sunscald treatment of applying an all-purpose fertilizer to the soil surface around the affected tomato plants; this can help stop further damage.
Prevention of Sunscald
Sunscald is very common with tomato seedlings. This is in part due to transplanting. When tomato seedlings are transplanted outdoors, they can be exposed to too much light which causes shock. When shock occurs tomato plants don't have enough energy to grow normally.
Hardening off tomato seedlings before transplanting is a way of getting them used to the environment outside. This does not mean that tomato plants are completely immune from sunscald, but they may be less likely to suffer it if they've already been hardened off and gradually exposed to outdoor light. This is why hardening off is so important when moving tomato plants from indoors to outdoors.
Hardening off involves gradually exposing tomato plants to the outside environment by taking them out of their pots and placing them in a sheltered, shaded area for a short period of time each day.
In order to prevent tomato seedlings from being affected by sunscald in the first place, make sure that they are hardened off before you transplant them outdoors and gradually expose them to outdoor light over a two-week period of time.
RELATED: Here's How to Fix Leggy Tomato Seedlings and Get them Ready for Planting
Proper watering is important for healthy tomato plants.
Seedlings are more susceptible to having leaves turn white due to sunscald and cold temperatures.
Solutions to sensitivity to cold temperatures
Tomato seedlings can be sensitive to cold temperatures and may experience stunted growth or die-off.
Make sure tomato plants are started indoors or in a greenhouse at the appropriate temperature.
It is critical to transplant your tomatoes when the soil temperate is above 60 degrees and there is no more chance for a tomato plant to get frost damage.
Do not expose tomato plants to temperatures below 50 degrees for more than a few hours at a time without taking measures to protect them from the cold weather, such as bring them inside or using row covers.
In order to avoid tomato plant damage due to low-temperature exposure, find yourself an appropriate tomato variety that will be able to survive and produce tomato fruit at the temperatures in your particular growing region.
Hardening off will prevent seedling leaves from turning white and will also help the plant grow strong and healthy, so make sure that if your tomato plants are sensitive to cold weather, you know how to protect them!
RELATED: Yellow Leaves on Tomato Plants? Here's Why and How to Fix It.
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Solutions to Fungal Diseases
Fungal diseases can also be a culprit in leaves turning white on tomato plants. A tomato plant can be susceptible to over-watering, which will lead to root rot and fungal diseases. Make sure you water only when needed and that your tomato is in well-drained soil to prevent the roots from becoming excessively moist at any point which would introduce pathogens or fungi into the tomato's system.
Some common fungal diseases that affect tomato plants are Alternaria or Septoria Leaf spot.
If your plant is already plagued with fungal diseases, you could try treating it with a fungicide.
Solutions to Nutrient deficiencies or too many nutrients
If tomato leaves turn white due to nutrient deficiencies, amend the tomato's soil with a fertilizer that is designed specifically for tomato plants.
A well-balanced tomato fertilizer will include nitrogen, phosphorus, and potassium. You might want to make sure there is also calcium and magnesium, as tomato plants also require these nutrients.
Another solution could be adding an organic compost tea made from cow manure and straw soaked in water as it contains nitrogen and phosphorus- two of the main nutrients needed by tomato plants.
If your tomato plant has too many nutrients, the tomato leaves will turn white. This can happen when a tomato plant is grown in soil that has too much nitrogen or phosphorus, which burns and damages tomato leaf tissue.
To correct the soil that has too much nitrogen or phosphorus, tomato plants should be grown in a pot with soil that has been amended to have less of these nutrients.
FAQS About Tomato Plants
Will tomato plants recover from sunscald?
Unfortunately, tomato plants that develop sunscald will not grow back. The best way to deal with sunscald on tomato leaves is to try to prevent it from happening in the first place.
How much water do tomatoes need?
Tomato plants don't need a ton of water, but they do require frequent watering. The tomato plants need to be watered more in the summer months and less when it is cooler outside. Tomato plants need about 1-2 inches of water a week.
Most tomato plant problems such as blossom end rot are caused by too much water or not enough water.
Tomato plant problems caused by too little watering are usually the result of a dry environment or soil that needs amending to better support tomato growth.
Can tomato plants be cured of nutrient deficiencies?
Yes, tomato plants that are nutrient deficient can recover from this by adjusting their soil with a fertilizer designed for tomatoes and adding mulch if necessary.
What fertilizer is best for tomato plants?
Tomato plants thrive in rich soil but need to be amended with a tomato fertilizer for proper growth.
Fertilizers should contain phosphorus and nitrogen as these are two major nutrients that tomato needs for healthy plant life. One that I recommend is Dr. Earth's Home Grown Fertilizer.
When is the best time to transplant tomato seedlings?
As with other plants, tomatoes prefer warmer weather. However, they tolerate a broad range of temperatures. If you live in a climate where winters are brief and cool (or nonexistent) I would recommend starting seeds indoors and transplanting them into the garden once all danger of frost has passed.
If you live in a climate where winter is long and cold I highly recommend that you purchase healthy starts from your local home improvement store or from an online seed supplier like Botanical Interests.
Here is an entire post I have dedicated to when to transplant tomato seedlings so you can have success!
Should I cut dead leaves off my tomato plant?
Yes - tomato leaves that are no longer alive should be cut off. This clears the way for new growth to emerge and allows plant food to supply more of what your tomato needs.
Preventing and Treating Tomato Leaves Turning White
In summary, tomato leaves turning white have a variety of causes and this article has addressed some common occurrences. The solution to these problems can be as simple as moving the plant away from direct sunlight, making sure that it is fertilized more often, or reducing your watering habits. We hope that this blog post has served as a helpful guide to why tomato leaves turn white, what might be causing it, and how you can fix it!
