With some good luck your Lowe's babies will fill the 1G pots with roots by fall. Overwintering 1G containers takes some extra efforts. I used MiracleGro with moisture crystals mixture. Worked well for me. I also learned that protection from heavy rains helps because showers wash out nutrients from containers. My potted Clematis became chlorotic after 2 weeks of rainy weather.
As for bareroot, soaking them in tepid water for several hours or overnight helps to hydrate them before planting.
Keep pinching new growth this year. That will stimulate root growth. It will also help to avoid forming a 1 vine leggy plant.

Alina, I like using the potting soil with moisture holding crystals also. It sure helps save time in the heat of the summer with excessive watering.

Jane, you don't necessarily have to bury the pots. It does help however in preventing excessive moisture evaporation from the pots over the summer if they are sitting in full sun.