The Richmond Register

June 18, 2013

Tomato problems

By Amanda Sears
Extension Agent

MADISON COUNTY — Tomatoes are the most popular vegetable grown in the United States, according to studies done at the University of Illinois. Despite being so popular, no vegetable or plant is problem-proof.  Here are some problems that may occur.


Fluctuating spring temperatures can be a problem for newly planted tomato transplants. To help get your tomatoes off to a good start, try using mulch around tomato transplants, such as newspaper, straw or black plastic with irrigation underneath it. The mulch conserves moisture and protects the tomatoes from diseases spread by water splashing onto the soil.

Blossom-end rot

A common problem is blossom end rot, which is a large black spot on the blossom end of the fruit.  Blossom end rot is not a disease. The major cause of this condition is fluctuating levels of soil moisture during dry spells. So watering your plants consistently with 1 inch of water per week will keep this condition at bay. Using mulches will also help.


Tomato cracking occurs in some varieties when there is a lot of rain after a dry spell. This is because the tomato absorbs so much water that the fruit wall cracks. Watering tomatoes consistently with 1 inch of water per week will alleviate this condition.

Blossom drop

Tomato blossom drop is very common with high summer temperatures. Tomatoes will drop blossoms when daytime temperatures in the summer are above 90 degrees. Blossoms will also drop earlier in the growing season when night temperatures drop below 55 degrees.


Sunburn is common on tomatoes that are exposed to sun on plants that have lost leaves because of disease or insect problems. The sunburned areas become tan to white, making the tomato susceptible to disease organisms. Control insects and disease to prevent leaf loss.

Leaf Curl

Leaves may curl after heavy rain falls. This is not a disease. It is a physiological condition that happens after heavy rains. It occurs on the older leaves.


“Catfacing" occurs on tomatoes exposed to cool night temperatures during flowering. Fruits are misshapen and have scars and holes on the blossom end. Older and large tomato varieties are more susceptible. The tomatoes are safe to eat.

White Spots

White spots on the skin of the tomato are caused by the feeding habits of the stink bug. The bugs stick their syringe-like mouthparts into the tomato causing the damage.

 If you have questions about these or other problems in your garden, contact me at the Madison County Extension Office, 859-623-4072.


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