Subclass Asteridae ( Asteridae )
Order Campanulales ( Campanulales )
Family Campanulaceae ( Campanulaceae )
Genus Lobelia — Lobelia.
Cardinal flower, scarlet lobelia — Lobelia cardinalis.
“1” A plant from the subtropical zones of North and Central America. The plant got its name thanks to its flowers, which it produces during blooming. The plant has light green leaves with brownish and reddish tones, which look wonderful among any other vegetation. Height 20-30 cm. Width 7-15 cm. As a stem plant, this lobelia can grow very large, and the water surface is by no means an obstacle for it. The stem is long, upright, fleshy, elastic, rounded, 0.2 cm thick, olive-green to wine-red in color, with noticeable scars of fallen leaves. They are simple, rounded, with downward-curved tips, green or light green, on thin petioles, up to 5 cm long, up to 3 cm wide. Phyllotaxis is alternate. The leaves are arranged in a spiral on the stem. The petioles are equal in length to the leaves. Under bright lighting, the underside of the leaves becomes violet-red. Veins are clearly expressed on the underside of the leaf, numbering about 9. It grows slowly.
“2” Unpretentious to the composition of water and soil, tolerates large temperature fluctuations. Prefers a temperature of 18-28°C, optimal 20-23°C, but can be higher (in this case, the leaves become somewhat smaller). Prefers soft or medium hardness water, with pH 6.5-7.2, hardness 5-15°. For good growth, truly bright lighting with an intensity of at least 0.5 W/l is required, otherwise the leaves begin to turn yellow. The duration of lighting is at least 8-10 hours. Such a daylight hours is optimal for it. Under strong lighting, the underside of the leaves becomes violet-red. Positively reacts to regular 25% water changes and the addition of liquid fertilizers. CO2 supplementation is desirable.
“4” The root system is well developed and consists of a single bunch of rather thick, white, short roots, requiring regular feeding. On the part of the stem free from leaves, aquatic adventitious roots develop – white, ciliated.
“5” It is advisable to plant the plant in the aquarium in groups in the foreground in the middle of the aquarium. Forms picturesque loose thickets. Forms not only straight stems, but also side shoots. In the aquarium, the top of the lobelia is pinched, which causes it to give side shoots, over time it grows and forms a real bush. With intensive lighting, the underside of the leaves takes on a red-violet color. Grows up to 5 cm per month. In “Dutch aquariums”, it is widely used in so-called “Leiden streets”, when a large number of cuttings are planted in the form of a “ladder” diagonally from front to back. Keeping conditions are simple. Under good conditions, it quickly reaches the water surface, emerges into the air and blooms.
“6” Propagated by stem division and separation of side shoots. To enhance the vegetative propagation of the plant, it is enough to pinch the top, which will cause accelerated growth of side shoots, which are then separated and rooted.
Identification: Cardinal flower — Lobelia cardinalis.
Dwarf cardinal flower — Lobelia cardinalis “Small Form”.
A compact form of the cardinal flower. Differs from Lobelia cardinalis by much rounder (like coins) leaves and much smaller growth. Forms picturesque sparse thickets that are appropriate in the foreground and middle grounds of a home body of water. The light green leaves of the lobelia look great against the background of other aquarium flora colored in rich green, reddish and brownish tones. Needs bright lighting with a daylight hours of at least 8-10 hours. Positively reacts to regular water changes and the introduction of liquid fertilizers. The root system is poorly developed and serves only to fix the plant in the soil.
With strong lighting and the addition of CO2, it becomes dense and lush, concentrating most of its growth on the production of daughter plants, which can be cut and replanted. Internodal roots under these conditions will be hidden by numerous side shoots and dense foliage. Under less optimal conditions and weak lighting, the plant will become leggy and less attractive, producing fewer side shoots. In large aquariums, this plant can even be used as a low foreground. Propagated vegetatively by cuttings. It feels best in water with T 22-24°C, pH 6.5-7.2, dH 5-15.
Ceratophyllum demersum, Ceratophyllum submersum.
Cabomba furcata, Cabomba palaeformis, Cabomba pulcherrima. 
