The fern is a fine-textured evergreen that thrives in high humidity and moderate temperatures. Ferns range from climbing to tree-like and have more than 12,000 species. This ornamental plant provides an excellent selection for the indoor environment. Though the indoor fern thrives vigorously in temperatures between 68 and 72 degrees F, maintaining the fern's ideal humidity level can be a challenge.
Plant the indoor fern in a porous, well-drained potting container. Mix an equal amount of nutrient rich soil, clean sand and organic compost. Plant the fern the mixture, pressingly firmly to secure its position.
Keep the indoor fern in a moderately tempered location with higher levels of humidity. Choose a location such as a bathroom or aquarium to ensure constant humidity levels.
Protect the fern's fronds from sun damage by positioning it in a location with indirect sunlight. Keep the fern away from direct temperature sources, such as a heating vent or air conditioner.
Irrigate the indoor fern according to its individual needs. Adjust the levels--some ferns prefer very moist soils while others prefer a drier loam. Begin irrigation by soaking the soil thoroughly until the excess water flows from the container. Allow the plant to rest and return it to its location. Irrigate again when the soil levels begin to feel dry. Never allow the soil to dry out completely between watering.
Feed the indoor fern monthly during the growing season, from mid-spring through mid-fall. Use a well-balanced, liquid fertilizer and distribute at half strength. Fertilize the fern several days after watering to prevent burn.
Repot the indoor fern each spring. Remove the fern from its container. Divide overcrowded plants by separating them at the root system, using a sharp, sterile knife. Replant the ferns in fresh, well-drained containers with porous soil, such as the soil, sand, organic compost mixture.