Answer: Most commercial growers use a soilless mix, often composed of bark and sand, along with finely calibrated fertilization and watering schedule. They may also set more than one plug into a larger pot to create a thicker plant faster.
At home, I would suggest using a soilless mix for container plants along with a water holding polymer and a regular program of water soluble fertilizer at the higher label rate. Set the pots in a sunny location and keep the soil evenly moist but not soaking wet. Move the plants into progressively larger pots as needed to keep them from overcrowding, and pich them regularly every few weeks until mid July to encourage bushiness.
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