Most likely ran short of water.

That's a good point that I never thought about. But it's a matter of putting 2 and 2 together. BER is caused by an inability of the plant to move calcium around in it's tissues (it used to be ascribed to a calcium deficiency but it is not necessarily so), and magnesium is chemically very similar to calcium. So excess magnesium will interfere with calcium usage and uptake in plants. There has been some VERY odd advice running around that epsom salts *help* with BER. That's a complete myth.

I have already pruned them all off. I was just wondering for future knowledge. The plant does have signs of: Septoria Leaf Spot Blight and probably one other disease But the leaves that turn yellow and then will turn completely yellow. They look like they are lacking nitrogen and then wilt away.

From the manufacturer of roundup. https://www.roundup.com/en-us/library/using-roundup-weed-grass-killer-products-properly/how-soon-can-i-replant-after-using 1 Day After Application: Ornamental flowers, trees, and shrubs. 3 Days After Application: Lawn grasses, herbs, vegetables, and fruits. But What I use: Pronto Big N' Tuf 41% glyphosate weed & grass Killer.. At a tenth of roundup's price. . http://www.cdms.net/ldat/ldCHR003.pdf Start on Page 26 section 13.6 Vegetable crops. The best of the best in the instruction restrictions: Allow at least 3 days between application and planting. Spot treatment(Asparagus) - This product may be applied immediately after cutting, but prior to the emergence of new spears. you'd think it would kill the roots, I have 300 plants, works as directed without any dead or damaged plants. Also look at section 13.7 stating: Residues can be removed by 0.5 inch natural rainfall or by applying water via a sprinkler system. Label also directs how to treat spaces between rows and if people would follow directions they wouldn't kill their plants with roundup. Many EU countries have or are in the process of banning residential use of roundup, people just can't follow directions.