Once established, the lobelia plant requires little maintenance. … Lobelia should delight your garden with beautiful blooms about mid-summer, continuing on up to the first frost. Although not necessary, you can deadhead lobelia plants to maintain a neat appearance.

How do you deadhead lobelia?

If deadheading the flowers on the individual stems, head them back toward the base, so they aren’t sticking up above the foliage. Snip at an angle, so water will run off the cut if it rains. Alternatively, shear back the entire plant by half once the flowers have finished blooming and begun to dry out in midsummer.

How do you keep annual lobelia blooming all summer?

Water regularly. Lobelia requires consistent soil moisture for prolific blooms. Water the plants regularly in the absence of rainfall, so that the soil is moist but not soggy. To help keep the soil surrounding lobelia consistently moist, mulch with a 2-inch layer of ground bark or leaf mold.