Lobelia plant performs best with full sun to partial shade and rich, well-draining soil. Choose a site that receives at least 4-6 hours of direct sun. Follow these steps and space garden lobelia plants 6-18 inches apart, depending on the variety. 

1. Loosen the soil in the planting area and dig a hole slightly wider and deeper than the root ball.
2. Remove the plant from the nursery pot and tease out roots if potbound.
3. Set the plant in the hole with the base level with the
4. Backfill the hole with soil and tamp down slightly to remove air pockets. Water well. 

Soil:  Lobelia prefers rich, well-amended soil with a slightly acidic pH between 6.0 and 7.0. Mulch with a layer of compost to add nutrients, suppress weeds and retain moisture. For containers, use a high-quality all-purpose planting Mix.

Watering:  Keep lobelia evenly moist but not soggy. Overwatering may cause root rot or other diseases. Water regularly during extreme heat or prolonged dry spells. Too little water can cause plant stress, stunted growth, and fewer flowers or brown foliage.