Everybody asks how tall it gets. The question that decides whether a screen works is how dense it is at the height you need the screening.
A great many plants sold for screening are solid at eye level for six or eight years and then go bare at the bottom as they mature. The canopy lifts, the lower branches shade out and die back, and what was a wall becomes a row of trunks with a view through it. By then it has had a decade of growth and starting over is a genuinely unpleasant conversation.
So the first thing to establish is what is being screened and from where. A screen that has to block a neighbor's deck from a kitchen window is working at eight or ten feet. A screen blocking headlights from a road is working at three. Those are different plants and the second one is the harder brief, because low density is what most screening plants lose first.
The second thing is time. A screen is years, not seasons, and the number depends on install size and spacing more than on species. Planting closer buys speed and costs you later, when the row crowds itself and starts thinning from the inside.
And the plant has to survive the site. An exposed property line on open ground is the hardest spot on most properties, and it is where screens get asked for.
