Which of the following plants is often used for its trailing habit in containers and hanging baskets?

Lobelia is favored for its trailing habit, making it an excellent choice for containers and hanging baskets. This plant typically features cascading stems that produce a profusion of small, bright blue, purple, or white flowers. Its growth pattern naturally drapes over the sides of containers, creating a visually pleasing effect that enhances vertical spaces in gardens, patios, or decks.

Lobelia is particularly valued in container arrangements for its ability to complement other plants by filling in gaps and providing a lush, flowing appearance. Its growth is not only aesthetic but also functional, as it can help to soften the edges of pot arrangements, making them look fuller and more vibrant.

While Cosmos, Salvia, and Petunia can also be used in container gardening, they do not typically have the same trailing characteristics that make Lobelia stand out for this particular purpose. Cosmos tends to grow more upright, while Salvia and Petunia, although capable of being arranged in containers, do not create the same cascading effect that is desired for hanging arrangements.