Answer
To determine boron needs, grow seedlings to an early stage, then place in a hydroponic or similar culture. Vary culture media from 0 boron to a high concentration, using different seedlings. Follow seedlings for growth and reproduction to determine if boron is essential.
Work Step by Step
Basically, look at similar experiments described in the chapter, and substitute tomatoes and boron for the plants and nutrients used as examples in the book.