Origin
Lobelia cardinalis L. var. graminea (Lam.) McVaugh, commonly known as grass-leaved cardinal flower, is a perennial herbaceous plant belonging to the genus Lobelia and family Campanulaceae. It is native to North America, specifically in the eastern and central regions of the United States and Canada. The plant grows in wetlands or near water bodies such as swamps, marshes, and riverbanks.
Common Names
Apart from its scientific name, Lobelia cardinalis L. var. graminea has several common names. These include grass-leaved cardinal flower, lobelia, cardinal flower, bog cardinal flower, scarlet lobelia, red lobelia, and queen Victoria cardinal flower. These names are due to its blossoms that resemble the bright red robes worn by Roman Catholic Cardinals, as well as royalty.
Appearance
Lobelia cardinalis L. var. graminea is a perennial plant that can grow up to four feet tall and spread up to two feet wide. It has bright green leaves that are lance-shaped and grow up to six inches long. The leaves have pointed tips and are sharply toothed along the edges. The plant's name 'graminea' is derived from the grass-like appearance of its leaves, which are more narrow than the leaves of other varieties of Lobelia cardinalis.
The grass-leaved cardinal flower blooms from mid to late summer, producing striking tube-shaped blossoms that are bright red or crimson in color. The flowers grow on spikes that can reach three feet tall and have a long blooming period that can last up to several months. The plant's flowers are tubular, with petals that flare out at the top forming a five-pointed star. The flowers are very attractive to hummingbirds, bees, and butterflies.
Uses
Lobelia cardinalis L. var. graminea is grown primarily for ornamental purposes due to its showy, bright red flowers. It is suitable for planting near water features, in bog gardens, and moist, shady areas. The plant's nectar is an essential food source for pollinators such as hummingbirds, bees, and butterflies. Nevertheless, the plant is toxic and should be handled with care, as its sap can cause skin irritation and ingestion of its parts can lead to vomiting, nausea, and other symptoms in humans and animals.
Light Requirements
Lobelia cardinalis L. var. graminea (Lam.) McVaugh requires bright light conditions for optimal growth. It thrives best in direct sunlight or under a lightly shaded area. The plant must preferably have access to sunlight for a minimum of 6 hours daily.
Temperature Requirements
The ideal temperature for the growth of Lobelia cardinalis L. var. graminea (Lam.) McVaugh is between 22-25°C during the day and must not fall below 18°C at night. Maintaining this temperature is essential to foster growth, and it helps the plant to avoid stress.
Soil Requirements
Well-draining, nutrient-rich soil is necessary for the proper growth of Lobelia cardinalis L. var. graminea (Lam.) McVaugh. The soil must have a pH level between 6.0-6.8 and must be kept moist at all times. The plant may not grow correctly in compacted soil because it affects the root development and prevents proper nutrient absorption.
Cultivation Methods
The Lobelia cardinalis L. var. graminea (Lam.) McVaugh, commonly known as the cardinal flower, is a beautiful flowering plant that can be grown in pots or in gardens. It can thrive in full sun or partial shade and requires moderately rich, moist, and well-drained soil. If you are growing it in a pot, make sure it has good drainage and is large enough to accommodate the plant's root system.
The best time to plant cardinal flowers is in spring or early fall. If you are planting seeds, sow them shallowly and cover them lightly with soil. Keep the soil moist but not soggy until the seedlings emerge.
Watering Needs
The cardinal flower prefers consistently moist soil, but it does not tolerate standing water. Water the plant deeply once a week and allow the soil to dry slightly between watering. During hot and dry weather, you may need to water the plant more frequently. Overwatering can lead to root rot and other problems, so make sure the soil dries out somewhat between waterings.
Fertilization
The cardinal flower does not require a lot of fertilization, but it benefits from a light feeding in early spring. Use a balanced fertilizer with equal amounts of nitrogen, phosphorus, and potassium, and apply it according to the package directions. Too much fertilizer can lead to excessive vegetative growth and reduced flowering.
Pruning
The cardinal flower does not require much pruning, but you can pinch back the stems to encourage bushier growth and more flowers. Deadhead faded blooms throughout the growing season to promote new growth and maintain the plant's appearance.
Propagation of Lobelia cardinalis L. var. graminea (Lam.) McVaugh
Lobelia cardinalis L. var. graminea (Lam.) McVaugh, commonly known as cardinal flower, is a herbaceous perennial plant popular for its bright-red, tubular flowers. The plant is native to the Americas and is commonly found in wet, swampy areas or along river banks.
Propagation by Seed
The most common method of propagating Lobelia cardinalis is through seed. Seeds should be harvested when the capsules turn brown and the seeds can be easily shaken from their pods. To propagate, sow the seeds in a well-draining potting mix and cover with a thin layer of soil. Keep the soil moist and warm with temperatures between 60-70°F. Germination generally occurs within 14-21 days. Seedlings can be transplanted to their final location once they have developed a few true leaves.
Propagation by Division
Lobelia cardinalis can also be propagated by division in the spring when new growth emerges. Carefully dig up the plant and separate the root ball into smaller sections using a clean and sharp knife or garden shears. Each division should have several healthy leaves and roots. Plant the divisions in their new location in well-draining soil and water thoroughly.
Propagation by Cuttings
Propagation by stem cuttings is another option for Lobelia cardinalis propagation. Take softwood cuttings in the spring or early summer and remove the lower leaves. Dip the cut end in rooting hormone and plant in a well-draining potting mix. Keep the soil moist, cover the container with a plastic bag, and place it in indirect light. Roots should develop in 2-4 weeks, and the plant can be transplanted into its permanent location.
Disease Management
Lobelia cardinalis L. var. graminea is susceptible to several diseases. Here are some common diseases and their management:
Pythium root rot:
This is a soil-borne fungal disease that causes rotting of roots and subsequently affects the whole plant. The first symptom is wilting of the leaves near the base of the plant. To manage this problem, use pasteurized soil and replace the topsoil regularly.
Botrytis blight:
This is a fungal disease that causes a greyish-brown fuzz on the leaves and stems. It affects the plant during periods of high humidity. To manage this problem, remove affected parts of the plant and avoid excessive watering.
Xanthomonas leaf spot:
This is a bacterial disease that affects the leaves of the plant, causing yellow spots that later turn brown. To manage this problem, ensure that the plant is not overcrowded, and avoid overhead watering.
Pest Management
Lobelia cardinalis L. var. graminea is also prone to pest infestations. Here are some common pests and their management:
Aphids:
These small insects suck the sap from the leaves, causing them to curl and stunt growth. To manage this problem, use insecticidal soap or neem oil spray; remove heavily infested leaves, or use a strong stream of water to dislodge them.
Whiteflies:
These tiny insects lay eggs on the undersides of leaves, and their larvae suck sap from leaves, yellowing and curling them. To manage this problem, use insecticidal soap, neem oil, or sticky traps to kill the adult whiteflies.
Spider mites:
These tiny red or brown mites are barely visible to the naked eye, but they can damage leaves by sucking the sap and causing yellowing and curling. To manage this problem, increase humidity around the plant by misting it regularly, or use insecticidal soap or neem oil.
