10 Common Tomato Problems and How to Fix Them Fast
Growing tomatoes can feel effortless one week and frustrating the next.
A plant that looked perfectly healthy yesterday may suddenly have yellow leaves, curled foliage, spotted leaves, cracked fruit, or flowers that fall before producing tomatoes.
The good news is that many tomato problems can be identified by the symptoms they produce. Some are caused by diseases or insects, while others are related to watering, heat, nutrition, sunlight, or rapid changes in growing conditions. University extension guidance emphasizes that good watering, nutrition, airflow, variety selection, and sanitation can reduce many common tomato problems.
Before reaching for fertilizer or pesticides, identify the symptom first.
Here are 10 common tomato problems and the fastest practical steps to address them.
Why Tomato Problems Happen
Tomatoes are relatively demanding plants.
They need adequate sunlight, moisture, nutrients, airflow, and warm growing conditions. Penn State Extension recommends at least six hours of direct sun daily, with tomatoes generally preferring warm daytime conditions and nighttime temperatures above about 60°F once established.
Problems often become worse when plants experience sudden changes.
For example:
- Drought followed by heavy rain can cause fruit cracking.
- Irregular moisture can contribute to blossom end rot.
- Extreme heat can cause leaf curl and interfere with fruit production.
- Poor airflow can encourage foliar disease.
- Excessive pruning can expose fruit to intense sunlight.
- Heavy nitrogen applications can encourage excessive vegetative growth.
The first step is therefore not always "feed the plant."
Sometimes the best solution is simply more consistent growing conditions.
1. Blossom End Rot
What it looks like
The bottom of the tomato develops a tan, brown, or black sunken area.
It may look leathery at first and eventually become soft or rotten.
Blossom end rot is particularly common on developing fruit, and larger tomato varieties can be more susceptible.
What causes it?
Blossom end rot is associated with inadequate calcium reaching the developing fruit, but that doesn't necessarily mean your soil lacks calcium.
Fluctuating soil moisture, root damage, rapid growth, heat, and other environmental stresses can interfere with calcium movement into the fruit.
How to fix it
- Keep soil moisture consistent.
- Mulch around plants.
- Avoid damaging tomato roots.
- Don't overfertilize with nitrogen.
- Remove severely affected fruit.
- Use soil-test information before adding nutrients.
Important: Adding calcium blindly isn't always the answer. Blossom end rot can occur even when soil calcium is adequate.
2. Cracked Tomatoes
Cracks usually appear around the stem end.
They may radiate outward or form concentric circles.
Why are tomatoes splitting?
Rapid fruit growth combined with sudden changes in water availability is a major contributor.
A common scenario is:
Dry soil → heavy watering or rain → rapid fruit expansion → cracking.
Recent Penn State research and extension guidance also highlights the role of temperature, fruit exposure, cultivar genetics, and rapid changes in water availability.
How to reduce cracking
Keep moisture relatively consistent throughout the season.
Helpful strategies include:
- Water regularly during dry weather.
- Apply mulch.
- Avoid letting plants become severely drought-stressed.
- Avoid sudden heavy irrigation after prolonged dryness.
- Maintain healthy leaf cover.
- Choose varieties with better cracking tolerance.
- Harvest susceptible fruit as they begin to color rather than waiting too long.
Don't remove large amounts of foliage unnecessarily. Good leaf cover can help protect fruit from intense sunlight and temperature fluctuations.
3. Yellow Tomato Leaves
Yellow leaves can have many causes, so don't automatically assume the plant needs fertilizer.
Older leaves turning yellow can be associated with natural aging, nutrient issues, watering problems, root stress, or disease.
Look at where the yellowing begins and what other symptoms are present.
Check these first
Is the soil constantly wet?
Overwatering or poor drainage can stress roots.
Is the soil extremely dry?
Drought can cause stress and leaf problems.
Are there spots?
Yellowing combined with brown or dark lesions may indicate a foliar disease.
Is the entire plant pale?
Nutritional issues may be involved, but a soil test is more reliable than guessing.
Tomato disorders can result from environmental, varietal, and management conditions, so the complete symptom pattern matters.
Fast fix
Check moisture, drainage, roots, foliage, and recent weather before applying fertilizer.
4. Curling Tomato Leaves
Tomato leaves can curl upward or inward for several reasons.
One common non-disease cause is physiological leaf roll, which can occur during drought or environmental stress.
University of Minnesota Extension describes leaf roll as leaves curling upward and inward, sometimes becoming thick and leathery.
Heat can also trigger leaf curling. A 2026 University of Minnesota vegetable update reported leaf curl associated with hot weather and described it as a heat-stress response that may not reduce yield.
What to do
- Check soil moisture.
- Water consistently during dry weather.
- Avoid excessive pruning.
- Check plants for insects.
- Look for mottled or distorted new growth.
- Consider herbicide exposure if the newest leaves are severely twisted.
If leaves are curled but remain generally green and healthy, environmental stress may be more likely than a serious disease.
5. Early Blight and Other Leaf Spots
Brown or black spots on tomato leaves are among the most concerning symptoms for gardeners.
Early blight is a particularly common tomato disease.
University of Minnesota Extension describes early blight as producing dark spots on older foliage, often with concentric "target-like" rings and yellow tissue around the lesions. Severe infections can cause leaves to fall.
What to do
Start by removing severely affected leaves.
Then improve the growing environment:
- Keep foliage as dry as practical.
- Water at soil level.
- Improve airflow.
- Avoid overcrowding.
- Remove fallen infected plant material.
- Keep weeds under control.
- Rotate crops where practical.
- Consider disease-resistant varieties in future seasons.
If disease is severe, consult local extension guidance for appropriate fungicide options and application requirements.
Don't diagnose every brown spot as early blight, however. Tomatoes can suffer from multiple leaf spot diseases with similar symptoms.
6. Tomato Flowers Are Falling Off
You see flowers.
You get excited.
Then they drop without producing fruit.
This is often called blossom drop.
Temperature is a major factor. Penn State Extension notes that tomato blossom drop can occur when nighttime temperatures fall below approximately 55°F or rise above approximately 75°F.
Extreme heat can therefore temporarily reduce fruit set.
What can you do?
- Keep plants adequately watered.
- Avoid excessive nitrogen.
- Give plants enough sunlight.
- Reduce severe environmental stress where possible.
- Be patient when temperatures become more suitable.
If the plant is healthy but weather conditions are extreme, the problem may correct itself when temperatures moderate.
7. Sunscald on Tomato Fruit
Sunscald looks like a pale yellow, white, or grayish patch on the side of the tomato exposed to intense sunlight.
It can eventually become dry and paper-like.
University of Minnesota Extension explains that sunscald is more likely when tomatoes lose enough foliage to expose fruit directly to strong sun.
Why it happens
The problem often becomes noticeable after:
- Severe leaf disease
- Insect damage
- Excessive pruning
- Sudden loss of foliage
How to prevent it
Protect the plant's natural canopy.
Don't strip healthy leaves simply to make the plant look tidier.
If fruit has already developed sunscald, the damaged area won't recover. Remove severely damaged fruit if decay begins.
8. Tomato Pests
Tomatoes can attract numerous insects.
Aphids, caterpillars, whiteflies, and other pests can damage foliage or fruit.
Start with inspection
Look underneath leaves.
Check:
- New growth
- Leaf undersides
- Flower clusters
- Stems
- Fruit
- Soil around the plant
Aphids, for example, can cause curling, stunting, and wilting when populations become significant.
Fast pest-management approach
Use an integrated pest management strategy rather than automatically spraying the entire plant.
- Identify the insect.
- Determine whether damage is significant.
- Remove pests manually when practical.
- Encourage beneficial insects.
- Use the least disruptive effective control when necessary.
- Follow the product label if a pesticide is used.
Identification matters because not every insect found on a tomato plant is harmful.
9. Tomato Plants Are Wilting
Wilting is a symptom, not a diagnosis.
A wilted plant could simply need water—or it could have a serious root or vascular problem.
Check the soil first
If the soil is dry and the plant perks up after thorough watering, drought stress may be responsible.
If the soil is moist but the plant remains severely wilted, investigate further.
Look for:
- Stem discoloration
- Root damage
- Disease symptoms
- Insect damage
- Poor drainage
- Recent root disturbance
Also consider whether the plant has experienced extreme heat.
Don't respond to unexplained wilting by simply adding more water. If the roots are already sitting in saturated soil, additional irrigation can make the situation worse.
10. Tomatoes Won't Ripen
Sometimes the plant is covered with green tomatoes but they seem stuck.
Temperature is one factor.
Tomatoes ripen best within a relatively moderate temperature range. Penn State notes that mature green tomatoes ripen optimally around 63–70°F, while temperatures above 80°F can interfere with normal ripening.
What can slow ripening?
- Excessive heat
- Very cool temperatures
- Heavy plant stress
- Excessive foliage in some situations
- Variety characteristics
- Fruit maturity
During periods of extreme heat, patience may be more effective than adding fertilizer.
Don't assume that a plant covered in green fruit needs more feeding.
Fast Tomato Troubleshooting Checklist
When something suddenly looks wrong, run through this checklist:
Leaves are yellow
Check:
- Soil moisture
- Drainage
- Nutrient status
- Leaf spots
- Root health
Leaves are curling
Check:
- Heat
- Drought
- Aphids
- Herbicide exposure
- Distortion of new growth
Fruit is black on the bottom
Think:
Blossom end rot.
Improve moisture consistency and remove affected fruit.
Fruit is cracking
Think:
Rapid growth + moisture fluctuations.
Maintain consistent soil moisture and good leaf cover.
Leaves have dark target-like spots
Think:
Possible early blight.
Remove affected foliage and improve sanitation and airflow.
Flowers fall without fruit
Check:
Temperature and environmental stress.
Fruit has pale sun-facing patches
Think:
Sunscald.
Preserve healthy foliage and avoid unnecessary pruning.
Plant wilts
Check:
Water, roots, drainage, heat, pests, and disease.
Green fruit won't ripen
Check:
Temperature and overall plant stress.
How to Prevent Tomato Problems Before They Start
The best tomato "fix" is often prevention.
1. Start With Healthy Plants
Choose vigorous plants and varieties suited to your climate.
2. Give Tomatoes Enough Sun
Aim for at least six hours of direct sunlight daily.
3. Keep Moisture Consistent
Avoid the cycle of severe drought followed by heavy irrigation.
4. Mulch Around Plants
Mulch can help moderate soil moisture and reduce rapid drying.
5. Avoid Excessive Pruning
Healthy foliage protects fruit and supports photosynthesis.
6. Don't Overfertilize
More fertilizer does not automatically mean more tomatoes.
Excessive nitrogen can contribute to excessive vegetative growth and is associated with blossom end rot under some conditions.
7. Improve Airflow
Give plants enough room and avoid creating a constantly damp canopy.
8. Inspect Plants Frequently
Five minutes of inspection can help you catch insects and disease before problems become widespread.
Frequently Asked Questions
What is the most common problem with tomato plants?
Common tomato problems include blossom end rot, fruit cracking, leaf spots, leaf curl, sunscald, blossom drop, pests, and watering-related stress. The exact problem depends on the symptoms and growing conditions.
Why are my tomatoes turning black on the bottom?
A black or brown sunken area on the blossom end is characteristic of blossom end rot. It is associated with calcium movement problems in developing fruit, often influenced by inconsistent moisture and environmental stress rather than simply low soil calcium.
Why are my tomatoes splitting?
Tomatoes commonly crack when fruit growth is rapid and soil moisture changes sharply, such as when heavy rain follows a dry period. Consistent watering and mulch can reduce the risk.
Should I remove yellow leaves from tomato plants?
Remove leaves that are dead or seriously diseased, but don't remove healthy leaves simply because they're older or slightly yellow. First determine why the leaves are changing color.
Why are my tomato leaves curling?
Curling can result from drought stress, heat, aphids, viruses, herbicide exposure, or other conditions. Upward or inward curling of otherwise healthy leaves can occur as a response to environmental stress.
Why are my tomato flowers falling off?
Extreme temperatures can interfere with pollination and fruit set. Very cool or hot nighttime temperatures can cause blossom drop.
What causes brown spots on tomato leaves?
Several diseases can cause brown or dark spots. Early blight often begins with dark spots on older lower leaves and can develop concentric rings. Other diseases can produce similar symptoms, so accurate identification matters.
How do I stop blossom end rot?
Maintain consistent soil moisture, mulch the root zone, avoid root damage, and fertilize based on soil-test recommendations rather than adding nutrients blindly. Remove affected fruit so the plant can focus on developing healthy fruit.
Why are my tomatoes getting white patches?
White, pale, or grayish patches on fruit exposed to strong sunlight can indicate sunscald. Maintaining healthy leaf cover can help protect fruit from excessive direct sunlight.
Why won't my tomatoes turn red?
High temperatures can slow normal ripening. Mature green tomatoes generally ripen best under moderate temperatures, while temperatures above about 80°F can interfere with normal ripening.
How often should I check tomato plants for problems?
During active growth and harvest, inspect plants regularly. Checking leaves, stems, flowers, fruit, and soil every few days makes it easier to identify new problems before they become severe.
Conclusion
Tomato problems can look alarming, but many have recognizable symptoms and manageable causes.
If the bottom of the fruit is black, investigate blossom end rot. If the fruit is splitting, look at moisture fluctuations. If leaves are curling, check heat, drought, pests, and other environmental stresses. If leaves develop dark spots, investigate fungal and bacterial diseases. And if flowers disappear without producing fruit, check the temperature before assuming your fertilizer routine is wrong.
The biggest lesson is simple:
Don't treat the symptom until you understand the cause.
Consistent moisture, healthy foliage, adequate sunlight, good airflow, appropriate nutrition, regular inspection, and suitable varieties can prevent or reduce many common tomato problems.
With a little troubleshooting, you can often turn a struggling tomato plant back into a productive one—and keep harvesting fresh tomatoes for much longer.
