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Common Diseases in Tomato Production

By Sally Mulambya – AgriCoop News

Most people think growing tomatoes is as easy as growing any garden vegetables unfortunately that isn’t the case and sure enough those that have been in the business long enough can testify. If you are a first timer in tomato production you are required to equip yourself with knowledge on how to cultivate and care for this delicacy.

Aside from learning how to prepare your soil, water levels or soil nutrients, asa first timer you need to understand the types of tomato varieties available and learn all thetechniques for disease and weed prevention, because despite all your care and attention tomato plant diseases will strike your garden.

These diseases are either caused by fungal pathogens, bacterial or viral. It is therefore, important that you learn the common diseases to quickly identify them when your garden is attacked in order to reap high yields.


This is divided into two. The Early Blight and the Late Blight,However, this is confused by many farmers to be the same despite the two having a huge difference.

Early Blight is a fungus that survives the cold seasons on old plantations on previous season and then pops back on your new plants in plantations in the new season. You will know its Early Blight when you see blackish-brown spots on the leaves, leaf drop off or see “sunburned” fruit.

The best solution is to clean up old vines when the season ends, dispose of in the trash and throw them away to keep the disease from spreading. Mulch your plants immediately after planting, rotate your planting areas and space the plants to allow for good air circulation.

You can also use a mixture of EpsoMicrostopBittersalt with Ecostyle Vital Fungicide which is all organic and recommended after clearing the plantation from the old plant. Spray it on the cleared land and let the land rest for a month before using it for another season.

Late Blight starts with leaves that appear water-soaked later turning brown and papery. The fungus is normally present when the weather is very wet enabling the spores to travel far infecting large areas. Like Early Blight, Late Blight is also preventable by keeping foliage dry, rotating crops annually and using certified disease free seedsas well as maintaining good air circulation around plants.

If you think that you have Late Blight, same treatment, discard infected plants in the trash and don’t compost. Also use of a mixture of EpsoMicrostopBittersalt with Ecostyle Vital Fungicide can be used as it is with Early Blight.


Blossom-End Rot

Blossom end rot sounds like it should be terminal, but a tomato plant can usually pull itself out of this nosedive. The rot looks like pale, brown or dark spots that turn black and flatten the bottom of the fruit due to a lack of calcium or uneven moisture. To avoid this reduce extreme swings in moisture – avoid allowing them to wilt or over watering tomato plants.

If you don’t think fluctuation in moisture is the cause, get your soil’s PH level tested. Too much nitrogen or soil that is too acidic or alkaline will limit the plant’s ability to absorb nitrogen. Lime will sweeten the soil and composted leaves will make it more acidic. Use a fertilizer that is low in nitrogen and high in phosphorous.


Fusarium and Verticillium Wilt

These are wilting conditions caused by an incurable fungal infection generally more common in warm conditions and sadly, these conditions have the capacity to wipe out an entire field, you should dispose of the plant immediately to save the infestation of others if discovered earlier do not add to the compost pile. Fusarium Wilt makes the leaves on one branch of the infected plant start wilting and yellow.

Verticillium Wilt is yellowing between the major veins on mature leaves.

Symptoms include drooping leaf stems’, sometimes an entire branch may wilt often starting with the lower portion of the plant and then progressing upwards

It is advisable to treat your areas of plantation with mixture of EpsoMicrostopBittersalt with Ecostyle Vital Fungicide before planting and constant treatment of such during the plant growth period and also disinfect tomato cages.



There are harmful Nematodes and the non harmful ones. These are generally invisible to our naked eyes. They are microscopic eel worms which are soil-born. It is sad to say but once they attack your plantation, there is no cure for them. They attack the root system causing the roots to swell. The only symptoms are stunted plants and discolored leaves. Fortunately, your tomato plants will still bear edible fruit, but once you’ve discovered the culprit, you will have to wait to address the problem. A common way to address this is to simply plant marigolds to fight them.


Tomato Skins Splitting or Cracking

Cracking or splitting happens because of sudden growth spurt from an increase in moisture after a dry spell. It can also occur when the fruit is overripe. To prevent this provide even moisture and choose plant varieties that are less prone to cracking. It is also advisable to pick the tomato fruits when they are ripe or almost ripe and/or just before a predicted rain storm to prevent cracking.


Yellow Leaves

Yellow leaves, depending on where you are in the warm season can spell trouble, or not. Late in the season, it’s just the tomato shutting down. If early on in the season you notice yellow, uncurled leaves at the bottom of the plant that work their way up that can signal a nitrogen deficiency or leaves turning yellow or brown higher up on the plant could be early blight. It’s best to do a soil test to determine if it is a nitrogen deficiency. Depending on the soil test result, you may need to supplement the soil with well-rotted manure or compost, both of which are high in nitrogen.

You can also apply a nitrogen rich organic vegetable fertilizer. Organic Plant Food Fertilizer which is a universal fertilizer is a good recommendation.



Sunscald happens when the tomato fruit is exposed to Ultra Violet rays from the scalding sun and in this case tomatoes may show yellow or white patches facing the sun. Provision of cages to shade them will protect them from sunscald. Using the EpsoMicrotopBittersalt will help the tomatoes develop quicker healthy foliage.


Bacterial Canker

This is a bacterial infection that usually appears at the edge of your tomato leaves. This disease is among the most difficult diseases to treat because it spreads quickly eventually causing plants to wilt and die.

Symptoms of this disease include: yellowish or brown edges.

For treatment you can use hydroxide or streptomycin spray and avoid planting your tomatoes in the same spot, if possible avoid planting tomatoes on the same area for at least three years.


Shiny, Sticky and Deformed leaves attacked by Aphids

Shiny, sticky & deformed leaves are caused by an aphid, whitefly or spider mite attack. Aphids suck the plant sap and excrete a sticky substance on the leaves and fruit. Look for the small, pear-shaped insects congregating on the top growth or on the undersides of the leaves.

They can be green, yellow or blackish. Spider mites make small yellow specks and spin fine webs on the leaves, making them feel sticky. White flies will fly up like a cloud when you brush the plant. Keep your tomato plants well-weeded but to overpower them you need reinforcements from a horticultural shop.

Flower Dropsy

Flowers that form but drop before fruiting indicate weather fluctuation. If the nighttime temperatures drop below 55 degrees or if the daytime temps are higher than 95 degrees with night time temperatures that don’t drop below 75 degrees, this can trigger blossom drop. Hot drying winds can intensify the problem. If the plant is not blooming during these periods, you have nothing to worry about however, if your flowers are dropping mulch to maintain moisture.

Farmers remember these are only some of the few common diseases in tomato production.there are several diseases in tomato farming that you need to be wary of, and remember to always consult trained agronomists for all your farm problems.

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