Frequently Asked Question

If the fruit on your tomato plant has brown or yellow water-soaked spot which appears on the end of the fruit where the blossom once was you probably have BER. As the tomato grows, this spot darkens, eventually becoming leathery and black, and may even cover half the fruit’s bottom.

Lack of calcium is often blamed for causing this, and while that is technically true, it really doesn't help you solve the problem because adding more calcium to the soil won't usually help. (eggshells in the soil is a #gardeningmyth for the most part) Here are a some conditions that can cause BER:

• uneven watering (drought, heavy rainfall, incorrect irrigation)
• rapid plant growth (too much nitrogen, rising temperatures)
• biologically inactive soil with no nutrient/mineral cycling microbes (potting soil, compacted soil, unmulched soil, over-watered soil, peat moss, etc)
• anaerobic (low oxygen) soil conditions (compacted soil, unmulched soil, over-watered soil)

BER occurs when the plant is growing faster than the calcium intake process is working, or when the plant is stressed in a way that causes the plant to not take in calcium.

Here are some things that can be done to help:

• improve soil health - bioactive and healthy soil helps to balance and provide everything the plant needs in correct proportions
• keep the soil mulched with at least 2 inches of organic matter (don't let it touch the stem) - mulch will regulate soil moisture and soil temperature, and it feeds soil organisms.
• plant tomatoes early before high-growth warm period
• don't fertilize too much, don't use strong fertilizers - if you have healthy soil and thick organic mulch, adding fertilizer should not be needed
• monitor the soil moisture (use your finger by sticking into the ground) and work to keep the moisture level constant by watering the correct amount as needed

Tomatoes showing BER can still go on to grow normal fruit later, and the damaged fruit can still be used by cutting off the bad spots.