common name: Fetus, Saint George's Sword, American Fern
Scientific name: Nephrolepis exaltata
Synonym:
Family: Polypodiaceae
Gender: Nephrolepis
Plant Type: Perennial
Origin: Inaccurate, because the genus is found in the tropical and subtropical regions of all continents.
Description: There are two species of the genus Nephrolepis, which are very common indoor ferns. Furthermore, there are numerous very different varieties of both species, so the indoor gardener has a wide choice of sizes and shapes. In all varieties, the foliage emerges from an underground and erect rhizome whose end is similar to a short, thick stem. The fronds, long and arched, are divided into numerous narrow pinnae that are inserted alternately on both sides of the midrib. On the underside of each pinna there are two rows of brown sera, one on each side of the midrib. These plants are particularly decorative when grown in a column. If given the right conditions, they grow actively throughout the year.
From the rhizome also emerge numerous tomentose filaments that crawl along the surface of the mixture, rooting and producing new plants at the end.
ADVISABLE SPECIES
N. cordifolia it has light green fronds that reach 60 cm in length and 10 cm in width at the base, narrowing to 0.5 cm at the end, and pinnae about 1 cm in width.
n. exaltata is similar to N. cordifolia, but the fronds can reach 1-1.50 m in length. More important than the original species are the varieties, among which are plants commonly known as the Swords-of-Saint-Jorge. In the most common form, each pinna is divided into numerous segments that give the plant a feathery appearance. The fronds are shorter than those of the original species.
CAUTIONS
Light: Keep ferns in bright light without direct sun. If needed, these fetuses can tolerate medium light for a maximum period of four or five weeks.
Temperature: Normal ambient temperatures are suitable throughout the year. Minimum tolerable temperature: 10°C. In temperatures above 21°, raise the humidity by placing the pot on a tray with wet pebbles and spray the foliage daily.
Watering: Never let these ferns dry out at root level. As long as the ambient temperature remains above 13°C, water abundantly as needed to keep the potting mix permanently moist. If the temperature dips below 13° for more than a day or two, allow the top third of the mix to dry out before watering again.
Fertilizing: Apply a liquid fertilizer every two weeks to actively growing plants grown in a peat-based mixture. Fertilize actively growing plants with a soil-based mixture every four weeks.
Bottling and Rebottling: Use a peat-based potting mix or a combination of earth and leaf soil mix in equal parts. When the roots of a nephrolep have filled the pot, repot in spring, moving the plant to a pot the size above. Once the pot has reached the maximum convenient size, remove the plant from the pot in spring, carefully cut off some of the outer roots and place the plant back in the same pot, after being thoroughly cleaned. Add the necessary fresh mixture.
Special notes: Sometimes, in the very feathery varieties of N. exaltata, some fronds degenerate, becoming similar to those of the type species. Cut long fronds that are not sufficiently segmented as soon as they appear. If they are allowed to survive they will spread and soon the whole plant will be degenerate.