Black spot/hole on the bottom of tomatoes?

Question

Some of the tomatoes in my garden have black spots that cover the bottom of them. It looks like something has been eating them. Could this damage be caused by crickets? There are a lot of them in the garden. If so, how can I get rid of them in a non-chemical way? Also, the 'black hole' only occurs on the tomato plants that are not in cages (we have around 20 tomato plants and only 10 cages), thus, the vines are on the ground.
I live in Michigan, if that helps. Thanks for any and all advice!

Answer 1

Sorry for the problem you are having. What you have is called "blossom-end rot". From NC State University:

"Blossom-end rot of tomatoes is a physiological disorder caused by a lack of sufficient calcium in the blossom end of the fruit. This disorder results in the decay of tomato fruits on their blossom end. Dry brown or tan areas the size of a dime, that grow to the size of a half dollar, characterize this disorder. This disorder is usually most severe following extremes in soil moisture (either too dry or too wet)."

Check the link below for further information on how to prevent this problem in the future. Hope this helps!!

Answer 2

Q: What causes a big black spot on my Tomato Plants?

A: The problem is called Blossom-End Rot = (BER), and is caused by a lack of calcium within the fruit. When calcium reaches low levels in the tomato, the fruit simply dies back at the bottom leaving the characteristic black or brown spot. Calcium is present in most soils in adequate amounts. The problem is that the plant cannot absorb enough calcium through its roots because of dry soil conditions. That's because calcium is taken up by the roots along with water. If, for some reason, water uptake is restricted, calcium uptake will stop.

Q: What can you do about it?

A: Have your soil tested to make sure you have enough calcium in the soil. If you don't, add either limestone (if the soil's acidity level or pH is below 6.0) or gypsum. If calcium levels are adequate, the most important control measure is to maintain optimum soil moisture.

Whenever tomato plants are allowed to experience the slightest bit of water stress, you are causing BER. To maintain good soil moisture, try using a mulch of straw, leaves, or even grass clippings to prevent evaporation.

Tomatoes need about 1" of water per week as a minimum. If you do not get this through rainfall, you will need to apply the water. As a rough estimate, each tomato plant needs approximately 3-5 gallons of water each week.

If you use a mulch, this amount may be cut in half. When watering, don't lightly sprinkle the ground. Apply the water so it enters the ground and moves through the soil to a depth of 8-12 inches. Shallow watering only encourages shallow rooting which leaves tomato plants more prone to wilting."

Read More:
http://vegetablegardens.suite101.com/discussion.cfm/2451
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What Eats Crickets:

Anything that is a meat eater and can catch a cricket will eat it. Frogs, toads, snakes, birds, and even mammals, like fox, skunk and raccoon will eat crickets. That's why they hide during the day and have evolved long legs that help them escape from predators.

Read More:
http://www.pca.state.mn.us/kids/c-september.html

Answer 3

blossom end rot. i've gotten it before. i don't always throw the affected tomatoes out, sometimes i'll just cut off the bad part and eat them anyways. this year i got no blossom end rot but i did get some canker thing that went away. it seems it's always something and if not, the animals eat them.