Lobelia's trailing tendency is what makes it an ideal plant for a hanging basket. Clusters of blue, purple, pink, red or white flowers will spill over the sides of the container from spring through early fall, adding color to a porch or small apartment balcony. The fact that the plant is relatively easy to grow and care for makes this plant a good choice for new gardeners.
Choose a hanging basket drainage holes in the bottom, in whatever size you desire. Fill half full with a good quality potting soil that is well draining, such as one that contains peat moss.
Remove your Lobelia plants from their containers and set in the hanging basket arranging them as desired. Once they are where you want, add more potting soil to fill the basket to the top; gently firm the soil around the plants with your fingers. Hang your basket in a location that gets morning sun and is protected from mid-afternoon sun, which can cause your plant to dry out and wilt.
Water the hanging basket well after planting so that water runs out of the drainage holes. Keep watered daily so the soil does not dry out which can cause the plants to turn brown and start dying. If the plants do start to turn brown, trim off just the brown parts and water your basket well until water drains out the bottom; most of the time Lobelia will come back to life.
Feed your Lobelia plants with an all-purpose fertilizer once a month to encourage strong growth throughout the season. A liquid fertilizer works best; water in well after adding to the basket.
Pinch off spent flowers as your plant grows to encourage more vigorous growth. Lobelia is a fast-growing plant and will begin trailing over the sides of the basket in the first month after planting.