Name: Daisy I Reno, Nv (Zone 6b) Not all who wander are lost
Why do you think there is a risk of blossom end rot? Have you seen any developing on your tomatoes? Has it happened in the past in this garden?
Blossom end rot is caused by a lack of calcium in the soil. If your soil truly is low in calcium, the fix is to mix something like bone meal into the soil BEFORE you plant the tomatoes. The calcium source has to be in a place that the roots can grow through it as calcium is not water soluble.
But, the calcium deficiency could be caused by the soil being too dry. Tomatoes can't use the calcium out of dry soil.
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and proclaiming...."WOW What a Ride!!" -Mark Frost
President: Orchid Society of Northern Nevada