More lime will not help because the calcium would take too long to become available. BER is not from lack of calcium, but from lack of mobile calcium in the plant. Here's a thread I like. Scroll down the thread to Al Tapla's explaination. http://forums2.gardenweb.com/forums/load/contain/msg0514510630172.html This year I had som BER on my only SIP, and I threw everything but the kitchen sink at it including; calcium nitrate in the reservior, calcium nitrate foliar spray, gypsum in the reservior, and Texas Tomato Food in the reservior, which has extra calcium in it. My BER stopped (for now) fairly quickly, and I only lost about 10 Red Brandywines. After everything I did, still not sure what stopped it. Might have stopped by itself anyway, which is usually the case.

Growing Tomatoes FAQ: What is blossom-end rot? How can I prevent it? Blossom-end rot is a disorder of tomato, squash, pepper, and all other fruiting vegetables. You notice that a dry sunken decay has developed on the blossom end (opposite the stem) of many fruit, especially the first fruit of the season. This is not a pest, parasite or disease process but is a physiological problem caused by a low level of calcium in the fruit itself. Symptoms BER, or blossom-end rot usually begins as a small "water-soaked looking" area at the blossom end of the fruit while still green. As the lesion develops, it enlarges, becomes sunken and turns tan to dark brown to black and leathery. In severe cases, it may completely cover the lower half of the fruit, becoming flat or concave, often resulting in complete destruction of the infected fruit. Cause Calcium is required in relatively large concentrations for normal cell growth. When a rapidly growing fruit is deprived of calcium, the tissues break down, leaving the characteristic lesion at the blossom end. Blossom-end rot develops when the fruit's demand for calcium exceeds the supply in the soil. This may result from low calcium levels in the soil, drought stress, excessive soil moisture, and/or fluctuations due to rain or overwatering . These conditions reduce the uptake and movement of calcium into the plant, or rapid, vegetative growth due to excessive nitrogen fertilization. Management Adequate preparation of the garden bed prior to planting is the key to preventing BER. Insure adequately draining soil in the bed by adding needed ammendments, maintain the soil pH around 6.5 - a pH out of this range limits the uptake of calcium. Lime (unless the soil is already alkaline), composted manures or bone meal will supply calcium but take time to work so must be applied prior to planting. Excess ammonial types of nitrogen in the soil can reduce calcium uptake as can a depleted level of phosphorus. After planting, avoid deep cultivation that can damage the plant roots, use mulch to help stabilize soil moisture levels and help avoid drought stress, avoid overwatering as plants generally need about one inch of moisture per week from rain or irrigation for proper growth and development. Once the problem develops, quick fixes are difficult. Stabilize the moisture level as much as possible, feeding with manure or compost tea is recommended by many, foliar applications of calcium are of questionable value according to research because of poor absorption and movement to fruit where it is needed but many have reported that foliar application of magnesium (epsom salts) can effect added calcium uptake. Other various suggestions consist of powdered milk, crushed egg shells tea, bone meal tea, Tums tablets, etc. but prevention is the key. Some recommend removing affected fruit from to reduce stress in the plant. BER should not be confused with fruit abortion or inadequate pollination although the symptoms may appear similar. The onset of BER occurs only after the fruit is well on it's way to development while insufficient pollination problems terminate the fruit while still quite small. Here is a link that might be useful: BER FAQ

Romas and paste types in general seem to suffer from blossom end rot (BER) more than other varieties. I don't know why. It's thought to be due to lack of calcium in the fruit. This is not related to how much calcium you have in your soil, except if you had none whatsoever but that's not the case. It seems to be related to the plant's inability to to get calcium into the developing fruit. Stress seems to be the major factor and irregular watering is often the main culprit. But not always! It's quite common to have just one plant in an entire patch that suffers from BER. I wouldn't worry about it. It happens to almost everyone. This year we have BER in one plant in a big patch. It's a roma type. I've found that heavy mulching reduces the incidence of BER, but it doesn't eradicate it.

First and foremost, BER is a result of uneven moisture availability. This can occur because of actual surges and dry spells of rain or irrigation, excessive growth due to improper fertilization, or damage/constriction of the roots. Very rarely is true calcium deficiency the trigger, at least not in a garden that is properly fertilized. Veggie gardens require a steady supply of dissolved nutritional elements.......the plants take a lot from the soil in order to create the fruits and vegetables that we eat. Those elements must be replaced. Tomatoes are just one of the crops that have high calcium requirements. All of the assorted greens that I grow, for example are packed full of Ca for me....it must be replaced to the soil before the next crop. Here's a great fact sheet that explains BER. It really explains the disorder.