Answer: Pinching will force the plants to branch, so the more you pinch the bushier the plants will be. Pinching is partly done by eye to make a plant pleasing to you. A rule of thumb might be to pinch them back about every four inches, but keep in mind that pinching will also delay flowering. Your plants will grow best with maximum light and moderate temperatures along with adequate fertilization. You may also need to move them to larger pots as they grow to avoid them becoming rootbound.
Pinching simply means using your fingers to nip off the terminal bud -- but some folks will use a tool and take off a larger section being sure to cut just above a bud. If you have waited too long and need to take off larger pieces, say four to six inches, you can use those as tip cuttings and propagate them for even more plants.
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