Sometimes, a tomato plant will lose a few leaves during the season, and this is often no cause for concern. However, it is much more serious when a tomato plant loses most or all of its leaves at once.
So, can a tomato plant survive without leaves? A tomato plant can survive for a short time without leaves, as long as it has enough stored energy to grow new leaves. A tomato plant with no leaves will grow slowly in the short term. If pests or disease caused the loss of leaves, then the tomato plant may not be able to survive.
Of course, whether a tomato plant survives with no leaves depends on how much energy it has stored and how fast it can grow new leaves.
In this article, we’ll talk about why tomato plants lose their leaves and how it affects them. We’ll also look at ways to treat the problems that cause leaf loss.
Let’s begin.
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Can a Tomato Plant Survive Without Leaves?
A tomato plant can survive without leaves in some cases. If the plant has enough energy stored, it can produce new leaves and start growing again.
However, certain diseases will cause leaf drop in tomato plants, and the plant will not be able to recover.
- Sunscald of plant and fruit, due to lack of shade from leaves
- Reduced photosynthesis due to lack of leaves (less sunlight absorbed means lowers energy production)
- Stunted growth due to lack of energy
- Fewer flowers and fruit due to lack of energy
Why Do My Tomato Plants Have No Leaves?
There are several reasons that a tomato plant loses its leaves, including:
- Transplant shock (lack of hardening off)
- Diseases
- Pests
We’ll start with transplant shock, since this is a common and preventable reason that young tomato plants lose their leaves.
Tomato Transplant Shock (Lack of Hardening Off)
Whether you buy tomato seedlings or start your own seeds indoors, you will need to transplant them into the garden at some point. When you do, there is a chance that some of the plants will suffer from transplant shock.
According to Gardening Dream, transplant shock occurs when plants experience a drastic change in environment. For example, more sunlight or fluctuating temperatures could cause transplant shock for a tomato plant.
Transplant shock will temporarily stunt the growth of affected plants. In some cases, transplant shock will cause leaves to dry out or turn brown and then fall off. The plant may not always be able to survive.
Part of the reason for transplant shock is that plants adapt to the environment where they grow. For example, the size and type of leaves can vary depending on whether a plant grows in sun or shade.
According to Michigan State University, tomato plants will produce “shade leaves” when they grow indoors without much natural sunlight. These large, light green leaves are very efficient at capturing sunlight.
When the plant is moved outside into hot, bright, direct sunlight, it cannot cope with the change right away. The larger “shade leaves” get burned and may fall off.
Eventually, smaller, dark green leaves will grow at the top of the plant as it gets accustomed to its new environment.
Transplant shock can also occur if the roots of a plant are damaged during transplant. Root damage also decreases the chances that the plant will survive pests or diseases.
The best defense against transplant shock is to prevent it from happening in the first place. To do this, the solution is to harden off your tomato plant before moving it into the garden.
Hardening off is the process of helping a young plant to adjust to the outdoors slowly. This avoids transplant shock by ensuring a smooth transition from indoors (controlled conditions with few changes) to outdoors (unpredictable conditions).
You can learn more about how to harden off seedlings in my article here.
Tomato Diseases
There are also some tomato diseases that can cause a plant to lose its leaves, such as:
- Tomato Blight (early blight or late blight)
- Septoria Leaf Spot
Tomato blight is a well-known disease that affects tomato plants, so we’ll start there.
Tomato Blight
Tomato blight actually has two forms: early blight and late blight, both of which can also affect potato plants. Late blight is more deadly, and can completely destroy a crop of tomatoes or potatoes in a short time.
Early blight spreads readily in damp conditions, and can move from plant to plant if they are spaced too close together. Early blight is a fungal disease that appears on tomato plants in early to mid-season.
The plant’s lower leaves are affected first, and they will turn yellow or brown before falling off the plant. The stems and fruit can also be affected, but the plant can still survive.
(You can learn more about other causes of yellow leaves on the bottom of tomato plants here).
Late blight spreads via fungal spores that are carried by the wind, and it does well in cool, wet conditions. Late blight appears on tomato plants in mid to late season.
The plant’s leaves get green spots, which get larger and then turn brown. The stem and fruit will later become brown, and the disease can finish off the plant within a few days.
You can learn more about how tomato plants get blight (and how to prevent it) in my article here.
Both types of blight are encouraged by damp or humid conditions. They are also more likely to spread when plants too close together.
One of the best ways to prevent blight is to choose blight resistant tomato varieties. You can find a list of 10 blight resistant tomato varieties in my article here.
Septoria Leaf Spot
According to the University of New Hampshire Extension, Septoria Leaf Spot is a fungal disease of tomato plants. The fungi can survive over the winter in plant debris (leaves, stems, and fruit) in the soil.
The disease spreads by spores, and it spreads faster in wet or humid weather.
Spots usually first appear on the lower leaves of the tomato plant. Eventually, the leaves may fall off, and the entire plant can be defoliated (that is, all the leaves will be gone).
Septoria Leaf Spot can also cause spots on the stems of plants. However, the fruit itself is rarely affected.
To avoid this disease, keep the leaves of your plants dry, if possible. Water plants from below with a hose or drip irrigation system, instead of getting the leaves wet with a sprinkler.
You may also want to prune the lower leaves of tomato plants. This will prevent water from splashing infected soil onto the lower leaves of your plants.
Be sure to leave enough space between plants to prevent the spread of disease. Remove any infected plants to save the rest of your crop.
Tomato Pests
Tomato pests are another common reason that tomato plants will lose their leaves. A pest that feeds on a tomato plant can spread any disease it is carrying between plants.
Some pests will also feed directly on the leaves, causing damage or even completely defoliating a plant. For example, various types of worms will feed on tomato plants, including:
- Tomato hornworms
- Armyworms
- Cutworms
Often, these worms will feed on the leaves of your plants and use them as a staging ground for reproduction. For example, tomato hornworms and armyworms lay eggs on the bottom side of a leaf.
Cutworms chew through stems to cut off leaves. They may even sever the entire top of the plant if they chew through the main stem.
There are organic treatment methods available for worm infestations on tomato plants. You can learn more about the types of worms that eat tomato plants in my article here.
Should I Cut Dead Leaves Off My Tomato Plant?
Removing lower leaves, even if they are healthy, can also help to prevent disease. The bottom leaves are close to the ground, so they are more likely to be splashed by infected soil when it rains.
If the leaves on your plant are dead because of transplant shock, you can leave them on. There might still be nutrients that the plant can draw from the leaves to use for new growth.
If the leaves on your plant are dead because of late blight, you should remove the entire plant to prevent the disease from spreading to other plants. The plant will probably not be able to survive late blight, but you can at least save its neighbors.
If the leaves on your plant are dead because of early blight or Septoria Leaf Spot, you should remove the leaves to prevent the spread of disease. Whether you remove the entire plant or not is your decision.
A plant with early blight or Septoria Leaf Spot can still survive and produce fruit if you leave it in the garden. However, if you leave an infected plant standing, it is more likely that the disease will spread to other plants.
Will Tomato Leaves Grow Back?
Tomato leaves will grow back as long as the plant has enough energy stored to produce new leaves. Once the plant has a few new leaves, it can absorb sunlight, perform photosynthesis, and create energy to make more leaves.
Just remember that a temporary lack of leaves will slow down (stunt) the growth of a tomato plant. Also, a plant without leaves and lacking energy will be less resistant to disease.
Finally, a plant without leaves can suffer from sunscald, since the leaves that normally provide shade are not present. It might be a good idea to provide some shade to your plants until they can grow back some of their leaves.
Conclusion
Now you know what causes a tomato plant to lose its leaves. You also know what actions to take to prevent these problems in the future.
You can learn more about worms that eat tomato plants and their leaves in my article here.
If any of your tomato plants have broken stems, you can learn about how to fix them in my article here.
I hope you found this article helpful. If so, please share it with someone who can use the information.
You can learn about 13 interesting tomato facts here.
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~Jonathon