Are non-dividing cells just permanently in G1 phase?

One ysis question in AP Biology Lab 3 (mitosis/meiosis) is killing me. "If your observations had not been restricted to the area of the root tip that is actively dividing, how would your results have been different?" We examined an onion root tip under a light microscope, and saw cells in (mostly) interphase, prophase, metaphase, anaphase, and telophase. If another part of the onion was examined (so the cells wouldn't be actively dividing), would all of the cells be in interphase?