I have a sage that is starting to bush out with multiple branches, but I don't need any yet. Should I prune it back to just a couple inches tall? I plan to transplant it into the home garden this fall as it will be like a nursery bush at the end of the season.
One needs to define the goal for the plant more specifically.
• If you want the healthiest, most vibrant plant possible right now, don’t prune it. Do give it lots of water, room, etc.
• If you want a neat landscaping plant for the future, perhaps on the formal side, then cut it back to keep it on the small side. But as Giacomo says, don’t overdo it.
• If you want to minimize shock when you transplant it outside, you probably want something in between. Trim whatever gets quite gangly but not more, and don’t overdo the water.
My sage is forgiving, though I haven't grown pineapple sage specifically. That probably allows you a fair range of options, any of which is likely to give you a reasonably healthy plant.