When should I fertilize my tomatoes to ensure optimal growth and a bountiful harvest? Is there a specific timeframe or a series of indicators that signal when my tomato plants are in dire need of nourishment? Should I be mindful of the various stages of their growth, such as the transition from seedling to maturity, and how does this impact my fertilization schedule? Furthermore, are there particular signs to observe, such as changes in leaf color or growth patterns, that can guide my decision-making process? Would it be prudent to consider the type of fertilizer I am using, as different formulations may have varying effects on my plants at different growth stages? What about environmental factors—how do temperature, soil quality, and moisture levels play a role in determining the appropriate timing for fertilizing? In the quest for an abundant yield, how critical is the balance between over-fertilization and under-fertilization?