By Anthony Reardon

With summer vegetable gardens now in the ground and producing, many looming potential issues may be on your mind when it comes to one of the more popular vegetable crops: tomatoes.

Whether the issue is sunken ends, cracking fruit, or deformed or un-ripened fruit, the answer is typically something pertaining to the environment. But what should you be looking for in identifying these problems?

Blossom end rot: This condition shows as sunken, browned or bleached ends on fruit and it is caused by a lack of calcium in the soil. It can gradually be fixed with soil amendments. Inconsistent soil moisture and tomato variety also play a factor in prevalence. It can additionally appear on squash, peppers and melons.

Catfacing: Appears as severely deformed fruit with creases and cavities produced along the blossom end of tomatoes. If severe enough, the deformities create open wounds where pests, disease and bacteria can enter. Being selective with the tomato varieties being grown is the best method of mitigating this, as the cause is still largely unknown. Fluctuating weather patterns and soil temperature may be a factor.

Yellow shoulders: This condition shows as the top edges of tomatoes staying yellow or green and never ripening. Like catfacing, the cause of this is unknown, but being selective with varieties chosen to grow can help. Soil amendments for ideal nutrients may help with mitigation.

Sunscald: A sunburn that appears as bleached skin on the fruit. Occurs when the leafy canopy of the plant itself is too thin and not producing enough shade. Look to the overall health of the plant and amend care methods to fix the problem. More foliage will shade the fruit.

Cracking: Appears as cracks in the fruit. Often these are literal stretch marks from periods of rapid growth due to inconsistent water moisture. While this can only somewhat be mitigated with increased rainfall, increasing and then gradually decreasing water after rainfall may help. General monitoring of consistent moisture mitigates the problem.

Leaf roll: This symptom shows as the edges of the tomato plant leaves rolling in on themselves. It is a common indicator of plant stress due to weather, fast growth or pruning. It does not affect tomato yield. The plant will bounce out of it with time and proper care.

Low Yield: Too much nitrogen applied to tomatoes causes plants to yield very little, only encouraging excess foliage. Apply a low range nitrogen fertilizer once before planting and three times during the growing season. The larger the amount of nitrogen in the fertilizer, the more it should be diluted.

Much tomato care comes down to the environment it is growing in. So, remember, fertilize correctly, water efficiently and choose reliable varieties.

Anthony Reardon is the horticulture small farms agent at the Johnson County K-State Research and Extension Office.