Shanna had 6 / 2 = <<6/2=3>>3 surviving tomato plants.
She had 4 - 1 = <<4-1=3>>3 surviving pepper plants.
Thus, she had 3 + 3 + 2 = <<3+3+2=8>>8 surviving vegetable plants.
Each gave her 7 vegetables, so she had 8 * 7 = <<8*7=56>>56 vegetables to harvest in all.
#### 56