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How to Care for Lobelia Flowers


If you are growing lobelia from seeds, start themindoors 10 to 12 weeks before the last frost in your area. Place seeds on the surface of soilless potting mix in small pots, place under fluorescent lights and cover with plastic to keep the medium moist. Germination takes at least 3 weeks. Compost tea is made by soaking a burlap sack filled with manure in a bucket of water for 2 to 3 days. When the sack is removed, the resulting liquid is a rich compost tea which can be used for fertilizer. Lobelia flowers also grow well in containers. Follow the same general care guidelines, but choose an all-purpose potting soil and a large container with drainage holes in the bottom. Lobelia will grow in hanging baskets, planters and window boxes with ease.


Lobelia can be toxic when consumed. Keep the plant away from curious pets and children.

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.

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