Lobelia is an annual flowering plant which produces small colorful blooms and grows well in garden beds or containers. Lobelia flowers are valued for their use as edging plants. They are also known to attract butterflies and hummingbirds to the garden. Lobelia flowers bloom from late spring to late fall with a minimal amount of care. They bloom profusely throughout the growing season, and the elegant blue flowers will be sure to delight you.
Plant lobelia flowers in an area of the garden which receives full sun to partial shade, and has well-drained average soil. Plant seedlings in the spring after the last frost. Dig planting holes the same depth the seedlings were previously growing and at least 6 inches apart. Cover the roots with soil and water thoroughly.
Water lobelia once per day in hot, dry climates and once every other day elsewhere. Water twice per day if the temperature reaches above 100 F. Lobelia flowers do not like hot, dry weather, so it is important to keep them adequately watered when temperatures rise.
Apply a water soluble fertilizer to lobelia plants once per week during the spring and summer months. Refer to the manufacturer's instructions for proper dosage. You may also drench the soil surrounding lobelia with compost tea instead of using fertilizer, if desired.
Prune lobelia once per year in midsummer or anytime it begins to look leggy, dry or strained. Use scissors or small pruning shears to cut the foliage back to half its height, preferably just before applying fertilizer. When the temperature cools, lobelia will reward you with renewed,better looking foliage.