Boston fern care guide

Boston fern care at a glance

Care instructions for potted and hanging Boston ferns.

Boston fern care indoors

Indoors, give Boston ferns bright, indirect light, like near an east window or a few feet from a south window. Too little light makes fronds thin and pale. Direct sun scorches them.

Keep the soil evenly moist but not soggy. Check every 2 to 3 days and water when the surface just starts to feel dry. Never let the pot dry out completely, because the fronds crisp quickly.

Humidity is the biggest challenge indoors, especially in winter. Bathrooms with a window, a humidifier or a pebble tray help a lot. Keep ferns away from heater vents and air conditioning.

Boston fern care outdoors

Outdoors, Boston ferns thrive on shaded porches, patios and under trees. Morning sun is fine, but afternoon sun burns them. They grow outdoors all year in USDA zones 9 to 11.

Outdoor ferns dry out much faster than indoor ones. In summer heat, check daily and water when the top of the soil is dry. Feed with half-strength fertilizer monthly from spring to late summer.

Hanging basket care

Hanging baskets dry out fastest of all, because they're exposed to wind on all sides. Water until it drains out the bottom, often daily in summer. If the basket feels light, it's dry.

To rewet a basket that has dried out completely, take it down and soak it in a tub of water for 20 to 30 minutes, then drain. Rotate the basket every week or two so it grows evenly.

Boston fern winter care

Bring outdoor ferns inside before nights drop below 50°F. Before you do, hose them off and check for pests, and trim off any brown or damaged fronds.

Indoors for winter, give them your brightest spot out of direct sun and as much humidity as you can. Water a little less often but don't let them dry out. It's normal for a fern to drop some leaflets as it adjusts.

If you don't have a bright, humid spot, you can let a fern go semi-dormant in a cool garage or basement around 50°F to 55°F, watering only once or twice a month, then cut it back and move it out in spring.

Reviving a brown Boston fern

Most problems come from dry soil or dry air.

• Brown, crispy fronds: the soil dried out or the air is too dry. Cut brown fronds back to the base, soak the pot, and raise humidity. New fronds usually grow from the center within weeks.
• Shedding leaflets: dry air, low light or the stress of a move.
• Yellow fronds: overwatering, or old fronds aging out.
• Grocery store ferns: they're often root-bound. Repot into a slightly bigger pot with fresh mix.
• Epsom salt: it adds magnesium and can green up pale fronds, but only if the soil is short on magnesium. Regular balanced fertilizer is usually all a fern needs.