Expert: nick mccann - 7/28/2011

Question
I have patio tomatoes in pots.  They only get the a.m. sun.  Last year and this year some of them get a large brown spot on the bottom.  They usually only get a little larger than a golf ball size so I wind up cutting away almost the whole fruit.  What causes this to happen?

Answer
Hi Barbara, that is an affliction called Blossom end rot, essentially it is a Calcium deficiency in the soil causing that bottom browning on your tomatoes; it is very prevalent in container grown tomatoes because it is leached out after several Months of watering. Graduating container sizes, as the plant grows is one way of preventing this, for in order to do this, you must add new potting mix to the pot, therefore keeping the Calcium intact (Miracle-Grow potting mix). Another method is crushing "Tums tablets" and mixing it with the soil after a Month or so, therefore preventing a deficiency. Research "Calcium deficiency in tomatoes" and you will get a plethora of information. Nick