Monday, August 3, 2009

BER on Super Marzano Tomatoes in the SWC

I was sad to see some of the newer Super Marzano Tomatoes in the SWC have developed Blossom End Rot (BER). The Super Marzano Tomatoes in the SFG are fine. As are the other tomatoes in the traditional garden, SFGs and the other two SFCs.

BER is believed to be caused by calcium deficiency that may be induced by a number of environmental conditions. BER isn’t necessarily a lack of calcium in the soil, but the inability of the plant to metabolize the proper amounts of calcium. This can be caused by fluctuations in the plant’s water supply. Dry soil or damage to the roots can restrict water intake, preventing the plants from getting the calcium they need. Also, plants can receive too much water from either heavy rain, over irrigation, or high relative humidity.

I have spent a lot of time reviewing the posts on the GardenWeb forums on BER and several members whose opinions I value, have suggested waiting out the BER. The general advice is to avoid over-fertilization, supply consistent not excessive soil moisture levels, and patience. The plant adjusts and the BER goes away all on its own.

Our weather has changed over the past week or so. It is much warmer, more humid and we have had more sunshine than earlier this summer. I have been topping off the SWCs in the evening when I get home from work. Usually they are very thirsty, so they may be drying out too much during the day causing an inconsistent water supply.

So for now, I will be sure the SWC is topped off in the morning so that these tomatoes receive a consistent supply of water during the warmer days. It isn't possible to overwater the SWC as the extra water will drain out the drainholes. Other than that I will take a wait and see approach for now. Wish me luck!

Learn more about BER: Blossom End Rot (BER) in Tomatoes by Carolyn Male


  1. My tomatoes in my pots go through cycles. One batch of toms is riddled with BER and the next flowering group is fine. I agree with waiting it out.

  2. Thanks Ribbit. It's difficult to wait it out as I feel I should be DOING something.

  3. I have been fortunate this year not to have any BER - each year it seems we usually get one or two plants that go through some fruit set with BER. Usually if you correct the problem the remaining fruit set by the plant is fine. Nothing will fix the fruits that are already damaged. Unfortunately by the time you see BER the damage was done long ago. But future fruit set on that plant can be just fine - so waiting it out is the right way to approach it.

  4. I've had so much BER on my paste tomatoes, it's ridiculous....