While the 10-20 rep range is probably best for muscle growth for most people, most of the time - there is not a categorical answer for this.
You stimulate different fibers working heavy (5-10 rep), moderate (10-20 rep) and light (20-30 rep) weight ranges. An ideal workout would include a pretty even distribution of all of these rep ranges throughout a mesocycle.
Even more important is real, no BS-ing yourself progressive overload. Regardless of the rep range you're targeting for a specific lift, you should get closer to failure each week (by way of more reps, more volume and/or more weight) until you can't any more - then deload and start again.
You should also think about some variety in your lifts if you've been doing the same exercise for more than ~16-18 weeks consecutively (~2-3 mesocycles).
Also food.