Caring for Your Nephrolepis Cordifolia (Lemon Button Fern)

The nephrolepis cordifolia, also known as the lemon button fern or erect sword fern, is a popular and relatively easy-to-care-for houseplant. This compact fern is perfect for beginner plant parents or anyone looking to add some greenery to their home without too much maintenance.

Overview

The nephrolepis cordifolia is native to east Asia and belongs to the family Nephrolepidaceae. It’s a dwarf cultivar of the Boston fern and has delicate, bright green fronds with a distinct lemon scent when crushed. The fronds emerge from brown, hairy rhizomes that grow horizontally across the soil surface. This gives the plant a lush, full appearance.

Some key facts about the nephrolepis cordifolia

• Grows 12 inches tall and wide
• Thrives in bright, indirect light
• Prefers warm temperatures between 60-80°F
• Likes acidic, moist soil
• Water 1-2 times per week
• Mist leaves to increase humidity
• Toxicity: Non-toxic to humans and pets

Light Requirements

The nephrolepis cordifolia does best in bright, indirect light, although it can tolerate low to moderate light conditions Place your fern near an east or west-facing window where it will get gentle morning or afternoon sun Avoid direct southern sun exposure as it can scorch the fronds.

If you don’t have a bright window, you can supplement with a grow light. Just make sure to keep the light 12 inches above the plant to prevent leaf burn. As long as the fern receives about 6 hours of bright, filtered light per day, it will thrive.

Soil Needs

Use a fast-draining potting mix that retains some moisture. Aim for a soil pH between 6.0-6.5. You can buy premixed indoor plant soil or make your own by combining:

• 1 part peat moss or coco coir for moisture retention
• 1 part perlite or pumice for drainage
• 1 part compost or worm castings for nutrients

Make sure the pot has drainage holes to prevent soggy roots. Add a layer of pebbles at the bottom of the container to improve drainage.

Watering and Humidity

Keep the soil consistently moist but not soggy. Water when the top inch of soil becomes dry. The frequency will depend on factors like light, temperature, and humidity, but aim to water 1-2 times per week. Water less in the winter when growth slows.

Mist the fronds 1-2 times per week or use a pebble tray to boost humidity around your fern. The bathroom or kitchen are ideal spots since these rooms tend to be more humid. Just make sure the plant isn’t receiving direct sunlight in these locations.

Temperature

The ideal temperature range is 60-80°F. Avoid cold drafts below 55°F. You can move the plant outdoors in summer as long as temperatures remain above 60°F at night. Bring it back inside before the first fall frost.

Fertilizer

Only fertilize during the active growing season in spring and summer. Use a balanced liquid fertilizer diluted to half strength every 4-6 weeks. Too much fertilizer can burn the roots and cause leaf tip browning.

Pruning

Remove any dead or damaged fronds as needed to keep your fern looking tidy and encourage new growth. Use sterilized pruning shears and cut fronds off at the base of the stem. Never cut into the green parts of the plant.

Propagation

You can propagate new nephrolepis cordifolia by division or from offsets that sprout from the rhizomes. Carefully tease apart root clumps or separate sprouted offsets. Pot in a sterile soil mix and keep evenly moist while roots establish.

Common Problems

• Brown fronds – Usually caused by dry air or underwatering. Mist more frequently and water thoroughly when soil dries out.

• Leaf spotting/fungus – Can indicate overwatering or high humidity. Allow soil to dry between waterings and remove affected fronds.

• Leggy growth – Needs more light. Move to a brighter location.

• Root rot – Caused by soggy soil. Repot in fresh, well-draining soil.

Caring for a Nephrolepis Cordifolia Outdoors

The nephrolepis cordifolia can be grown outside year-round in USDA Hardiness Zones 9-11. In cooler zones, you can put the fern outside for the summer if temperatures remain above 60°F at night.

When growing outdoors, place in partial to full shade. Morning sun or dappled light is ideal. Make sure the soil drains well and doesn’t become waterlogged. Apply a 2-4 inch layer of mulch around the base to help retain moisture. Water whenever the top 1-2 inches become dry.

Bring the fern indoors or move to a sheltered spot before temperatures drop below 55°F. As long as you meet its basic care needs, a nephrolepis cordifolia makes a lush, easy-care houseplant or outdoor accent.

Tips for Success

• Acclimate new plants before repotting to avoid transplant shock
• Wipe dust off fronds with a damp cloth to keep them looking their best
• Rotate the plant periodically so all sides receive light
• Propagate by division every 2-3 years to control size
• Repot annually in spring using fresh potting mix

With its cascading green fronds and compact size, the nephrolepis cordifolia brings an airy, tropical feel to any indoor space. For best results, give this fern bright filtered light, consistent watering, and warm humid conditions. With a little basic care, you’ll enjoy this easygoing plant for years to come!