My basil is doing beautifully this year. I've got about 6-7 plants in containers on my deck. When I go out to snip some, I never know whether it's better to snip fewer stems at a point further down, or more stems just from the tops of the plants. I'm trying to stop them from flowering these days, so I'm tempted to snip from the tops, but my long-term goal is to keep my plants prolific until tomato season is over. Any advice?