Will TUMS Cure Blossom End Rot?

Home » Blog » Will TUMS Cure Blossom End Rot?

Robert Pavlis

People speculate that blossom end rot in tomatoes and peppers is caused by a lack of calcium in the soil. Many now suggest that dropping a TUMS (common brand of antacid) into the soil below each tomato or pepper will prevent this problem.

Will TUMS cure blossom end rot (BER)?

This is a very good example of a myth that can be debunked very easily, knowing nothing about BER.

Will Tums Cure Blossom End Rot?
Will TUMS Cure Blossom End Rot?

What Causes Blossom End Rot?

BER is caused by a lack of calcium in the fruit. The plant may have lots of calcium but if the plant does not move it to the fruit, the fruit gets blossom end rot.

From this last statement it becomes clear that soil with enough calcium in it, might still lead to BER. Soil that is deficient in calcium, which is not very common, will lead to BER because the whole plant can’t get enough calcium.

Why does a plant not move enough calcium to the fruit? This is still not fully understood, but watering has a lot to do with it. Either too much water, or not enough water will cause BER. The best way to solve the problem in the garden is to water regularly and mulch to keep moisture levels constant.

Growing Great Tomaotes, by Robert Pavlis

BER is more fully discussed in Blossom End Rot.

Will TUMS Cure Blossom End Rot?

TUMS contains a significant amount of calcium. If soil is deficient of calcium TUMS will certainly add calcium to the soil, which is then available to tomatoes and peppers.

Calcium deficiency is not a common problem in soils, so for most gardeners, TUMS will have no effect.

Lets assume a soil test was done and the soil is deficient of calcium. How many TUMS does it take to bring the soil back up to adequate levels?

The number will depend on the degree of deficiency and the target level you want. Spectrum Analytical provides a guideline (ref 1) and suggests adding between 500 and 1,500 pounds of gypsum per acre. Let’s go with 1,000 pounds per acre. Gypsum is 22% calcium, so we need to add 220 pounds calcium per acre.

An acre is about 44,000 sq ft, and 220 pounds of calcium is 99,660 g. Each sq ft would require 2.3 g.

The generic brand of TUMS on my desk has 0.75 g calcium carbonate per tablet which is 0.3 g of calcium. So you would need to add 7.6 TUMS for each sq ft of soil in order to add the necessary calcium.

A 10 x 10 ft garden (about 9 sq meters) would require 760 TUMS.

Does this sound like a cost effect home remedy for your garden? What effect do you think the common recommendation of one TUMS per plant has?

Microbe Science for Gardeners Book, by Robert Pavlis

This is such a silly myth that it has upset my stomach – good thing I have TUMS handy!


  1. Calcium in Soil; https://www.spectrumanalytic.com/support/library/ff/Ca_Basics.htm
  2. Photo source; Dave Lundy


If you like this post, please share .......

Robert Pavlis

I have been gardening my whole life and have a science background. Besides writing and speaking about gardening, I own and operate a 6 acre private garden called Aspen Grove Gardens which now has over 3,000 perennials, grasses, shrubs and trees. Yes--I am a plantaholic!

27 thoughts on “Will TUMS Cure Blossom End Rot?”

  1. Adding eggshells will add calcium in the long run, but I read that it takes many years for egg shells to degrade to usable calcium. I still see the egg shells in my composted soil so I think it’s correct, but still a good idea to compost the egg shells.

  2. I tried tums by putting it just under the root when planting and this year no blossom rot. Might be just the weather, but I will do it again next year. Your measurement of the amount of tums per acre is, to me, silly. No one expects to put tums over an acre. When fertilizing a garden you can broadcast or spot treat. You don’t broadcast miracle grow as mush as putting it in the ground in the hole before planting. A spot treatment of calcium under the plants roots would have more of an impact.

    • You did not read the post correctly. It does NOT calculate the number of TUMS per acre. It calculates the number per plant!

      You also missed the main point – BER is NOT normally a calcium deficiency!

  3. Used black cow manure, 4 crushed tums and egg shells last year and didn’t have BER.
    Used just black cow manure this year and have about 2 out of 10 tomatoes with BER.
    5 plants in the ground.

  4. I have noticed that in my tomato crops, BER occurs primarily on the first wave of fruiting. I’ve noticed that the flowers which produce this fruit with BER were either forming or formed just after transplanting the young plant from it’s pot to the garden. After reading what you’ve posted here, it would seem logical that the disruption of natural metabolic processes which I guess gets the term transplant “shock” may interfere with calcium uptake, among many other things. I haven’t set up an experiment yet but I’m planning one. Have you or anyone else noticed this pattern?

    • I planted 5 early girls this year. Started them Feb 1st. They took about a month to start flowering even though they were 2ft plus in height. Planted outside April 15th. 2 out of 10 tomatoes have BER….no BER last year and used Black cow, 4 tums crushed in hole when planted, egg shells in each hole. Started the early girls about march 15th last year.
      I’m spraying them with a calcium spray as of today…..I’m just about into my second batch of fruit…..the green tomatoes are golf ball size.
      I water them morning and night. About a quart each watering.

  5. I use tums in my staw bales. Very effective. And yes..have done controlled studies with bales with and without….The bales have NO Calcium without it and the ones without the Tums invariably have BER while the ones with the Tums have no problems… Have done this 4 years running with the same results.


Leave a Comment