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How To Stop Tomato Blight – 3 Simple Secrets To Keep Your Plants Safe!

Looking for the best way to stop tomato blight and keep your tomato plants healthy and productive this year?

Tomato blight are two words that strike fear into backyard tomato growers. Although there are several types and versions of the disease, blight is a fungal condition that can devastate and destroy otherwise healthy plants.

The disease is particularly devastating to plant species within the Nightshade family – including tomatoes, potatoes, peppers and egg plant. It is often made worse when conditions are overly wet and cool as it helps feed and fuel the pace of the spread.

first signs of tomato blight
The key to stopping tomato blight is prevention. Once the tell-tale signs of blight show up, it is usually too late to help the afflicted plant.

Unfortunately, once the first signs of tomato blight appear, it can be nearly impossible to keep it from eventually wiping out the plant. It usually starts out with the browning of leaves. Quite quickly, it will spread to the stems and branches, and depending on the type of blight, even the fruit.

Even worse, it can then spread easily to neighboring plants, wiping out an entire crop in the process.

How Blight Spreads – How To Stop Tomato Blight

Blight is spread through spores in the soil. The spores can get into the soil by several different means. They can be blown in from the wind, carried in and left by insects or animals, or even dropped onto the soil through rainfall.

They also can drop to the soil from infected plants above. Beyond heavily damaging or destroying the plants, once blight occurs, it unfortunately renders the soil where the crops are growing useless for planting tomatoes in the future. And it does so for several years afterwards.

keep tomatoes healthy - tomato plants
Once blight hits a plant area, you should not replant tomatoes in the same spot for at least 3 years to avoid continuing the problem. In some cases, an infected area can take five years before the spores die off.

In fact, once blight appears in a specific soil space, the spores can stay alive in the soil for up to 5 more years. All the more reason to prevent it before it ever becomes an issue!

Three Types of Blight – How To Stop Tomato Blight

Leaf Spot Blight

There are actually three distinct types of tomato blight. Early blight, Leaf spot blight, and Late blight.

Of the three, Leaf spot blight is by far the most common in the home garden. It begins to appear in late June to early July. Leaf spot starts with the lower leaves turning brown, then black, and finally rotting away.

Leaf spot will steadily begin to destroy all of the foliage of the plant, usually within 30 days of first appearing.

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Early Tomato Blight

Early tomato blight on the other hand will appear after the tomato plants have set fruit. This type of blight doesn’t directly damage the fruit. Unfortunately, it does destroy all of the foliage.

When it does, the tomatoes are left to endure the scalding hot sun without protection. This can lead to most of the fruit simply rotting away as it tries to ripen on the vine without protection.

Late Tomato Blight

Late blight starts as tiny, light-colored spots on the foliage of plants. It quickly progresses until the stems, leaves and tomatoes turn black.

Late blight is spurred on by cool, damp temperatures. It tends to be more of an issue in cooler climates, or in growing seasons that are extremely wet and rainy. Left to its own accord, Late blight will eventually spread to the fruit as well, ruining it in the process.

late blight
Late blight will usually hit both the foliage, and eventually the fruit as well.

How To Stop Blight – Prevention Is The Key To Healthy Tomatoes

The bad news is that once any of the above tomato blight symptoms have arrived, it is usually too late to help. Although you can remove damaged leaves and fruit as soon as you see them, blight usually will win in the end.

The real key is in prevention. There are actually quite a few things you can do that can help you avoid tomato blight. And you might be surprised just how easy they are!

How To Stop Tomato Blight – 3 Keys To Healthy Plants

#1) Crop Rotation

The number one way to keep tomato blight and disease from finding your tomato plants is by rotating your plants every year to a new location.

healthy tomatoes - how to stop blight
When growing tomatoes in containers, it is vital to change the soil ever year. Not only do tomatoes take nutrients from the soil as they grow, the soil can also become infected with the spores that cause blight.

Growing tomatoes in the same soil or garden space every year is an open invitation for blight. Tomatoes are highly susceptible to soil-borne disease. When they grow in the same space year after year, it increases the likelihood that those diseases might have become established, and are lying in wait.

Rotate tomatoes to a new location or soil space each year for a minimum of 3 years. If you are growing tomatoes in containers, replace the soil each season with new potting soil.

Not only does this help to prevent blight, it also keeps a fresh supply of nutrients in the soil. Those fresh nutrients don’t only help propel strong growth, but they help the plant to better fight off disease.

The Importance of Mulching Tomato Plants – How To Stop Tomato Blight & Keep Tomatoes Healthy

When it comes to preventing blight, mulch can play an extremely important role. As soon as you plant, you should mulch the area around your plants immediately.

pruning tomatoes to prevent blight
Pruning underneath your tomatoes will help decrease the chances of spores finding an easy ride. By pruning low branches and mulching, you give your tomatoes the best chance to avoid blight. Finally, be sure to support your plants so they won’t sprawl and contact the soil directly.

Spores that are alive in the soil can easily be splashed up onto the foliage directly. Especially if the soil is bare, making for an easy route for the spores to your plants. Every time a hard rain hits or when you water, your plants have the chance to become infected by the spores splashing up.

But with a heavy application of mulch covering the soil, the dirt can’t splash. Even more, mulching plants helps to cut down on weeds and keeps the soil temperature regulated.

In addition to applying mulch, it is important to prune and remove the bottom 6 to 12 inches of your plants foliage for this same reason. Keeping the plants up off the ground helps to keep disease away by keeping soil from directly touching the foliage. See: How To Prune Tomato Plants

Finally, don’t allow your plants to sprawl on the ground without support. Supporting plants with stakes or a tomato cage will help keep soil and the foliage from coming in contact, lessening the chance of infection.

Water With Care – How To Stop Tomato Blight & Keep Tomatoes Healthy

When and how you water can help to keep tomato blight in check as well. Watering is one of those mundane tasks that seems so simple on the surface, but it can cause immense damage if done incorrectly.

watering tomato plants
How you water your tomato plants can play a big role in their success, or failure.

It is important to water in the early morning so tomato plants have time to dry off. Wet and damp leaves are the ideal ingredient for spores to grow. Watering late in the day or at night will keep plants moist for extended periods.

That can lead to heavier dew levels in the morning, making plants even more prone to disease. To help keep moisture in check, be careful to water only the root zones around tomato plants and not the foliage. By watering this only this zone, you reduce the chance of splashing spores from plant to plant.

Final Notes – How To Stop Tomato Blight & Keep Tomatoes Healthy

Once planted, keep a careful eye on your tomatoes for any early signs of blight. If you do notice leaves or stems browning off, act fast to remove them to contain the spread.

By removing these fast, you may be able to save the plant. More importantly, you will keep the spores from dropping off the plant and infecting more soil and more plants. Always clean and disinfect your pruning blades before pruning a new plant to prevent cross-contamination.

Be careful not to place any of these trimmings in your compost pile. Instead wrap them in newspaper or a bag and put them in the trash. When placed in a compost pile, they can easily survive and infect plants the compost is used on.

You may not be able to treat tomato blight effectively once it occurs, but you can definitely help prevent it. As the old saying goes, an ounce of prevention is worth a pound of cure!

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