Tomato Blossom End Rot Caused By Improper Watering


Around the Twin Cities, many homeowners are incorporating some fruit and vegetable gardens as a part of their landscaping, even in the city.  The most popular home garden produce?  Tomatoes. There’s just something satisfying about serving up grilled burgers in your outdoor kitchen, and then topping them off with slices of tomato plucked fresh from your own yard.

If you’ve got tomatoes in your yard you’re probably beginning to see those yellow blossoms turn into small green tomatoes.  As your tomatoes are setting fruit, have you noticed rotten spots on the bottoms?  It could be blossom end rot.  It’s common to tomatoes, but it’s an environmental disease that affects peppers and squash also. There are many causes, but the most common is improper watering. It can also be caused by the plants having a calcium deficiency while the fruits are forming.

Blossom end rot usually starts to occur early in the growing season when all of the favorable growing conditions were present, but then what follows is a long period of drought during the fruit formation. In the early stages of development the cells at the end of the fruit don’t get enough water to grow. It can also occur after there have been periods of heavy rain which compacts the soil.  This causes the small rootlets to die because there is a lack of aeration in the soil. Also, when there are overdoses of nitrogen it can hinder the calcium being taken in which just causes and aggravates the condition. Heavy pruning of the tomatoes or peppers can result in blossom end rot also.

The symptoms in a tomato are when the there are sunken, dry, brown patches ranging to black, tough leathery spots near the blossom end of the tomato. In a pepper a lighter colored spot shows up near the blossom end of the fruit. It also causes about a third of the fruit to shrivel.

The prevention steps to take include assessing the method and the amount of water the plants are getting. Installing an irrigation system with a drip method might be more advantageous than having a spray nozzle hitting the tomato and pepper planting areas.  Watering plants consistently and evenly throughout the growing season will help. Check the pH of the soil with a soil sample test.  It should be between 6.0 and 7.0.  If it’s less than 6.0, add horticultural lime, which contains calcium. Also avoid using any excess nitrogen.

At ALD we specialize in landscape designs that reflect the vision of our clients.  If a vegetable garden dream is floating around in your head but you can’t quite figure out how to work it into your yard layout, give us a call.