Boston Fern Care: How to Grow Boston Ferns

Boston fern is the common name for Nephrolepis exaltata, a species of fern with many small, sword-shaped leaves. Other names for Boston ferns include sword fern, ladder fern, and boss fern. Boston ferns thrive as both indoor plants and outdoor plants—particularly in warm, humid climates like Florida. A hanging basket on a moderately sunlit porch makes a great location for a Boston fern.

At maturity, Boston ferns grow to be about two to three feet tall and wide. With proper Boston fern care, you can keep this perennial plant for years.

Boston ferns may differ in appearance and size. You may also notice differences in the frond color of each cultivated variety, or cultivar.

1. 1. ‘Compacta’: This cultivar of Boston fern is short and stout with vivid green fronds.
2. 2. ‘Rita’s Gold’: Similar to the ‘Compacta’ cultivar, ‘Rita’s Gold’ is short and stout but with yellow-green fronds.
3. 3. ‘Golden Boston’: The ‘Golden Boston’ variety is typically embellished with bright yellow leaves.
4. 4. ‘Fluffy Duffy’: Small and dense with feathery textured fronds, ‘Fluffy Duffy’ is a popular houseplant variety.
5. 5. ‘Florida Ruffle’: Feathery like the ‘Fluffy Duffy’ but larger, the ‘Florida Ruffle’ variety of Boston fern makes a great outdoor plant.
6. 6. ‘Dallas’: One of the few Boston fern varieties that can survive at lower humidity levels, this variety is known for fast and widespread growth.
7. 7. ‘Whitmanii’: Another cultivar that can thrive in lower humidity, the ‘Whitmanii’ fern is recognizable for its delicate, feathery look.

Whether you want to add a new plant to your living room or backyard garden, planting a Boston fern requires a few steps. Before you set out to plant your Boston ferns, make sure it’s the optimal growing season of fall or spring.

1. 1. Choose well-draining soil. The right potting mix or garden soil for your fern is enriched with peat moss and sand for drainage.
2. 2. Choose a large enough pot. When choosing a pot, look for one that is sufficiently large so that your fern’s roots will have plenty of distance from the drainage holes. Allowing the roots to have room will help prevent destructive root rot.
3. 3. Plant your Boston fern deep enough in the pot. Fill the pot halfway with potting mix, and plant your fern root ball about halfway down from the top of the pot. Then, fill in the remainder of the pot with the soil mix until you reach about one inch from the rim.
4. 4. Choose an outdoor spot with partial sun. A mix of indirect sunlight and direct sunlight is ideal. When placing your fern plant outdoors, select a spot where the soil will stay moist. Ideally, the humidity levels in your planting location should stay above 50 percent and the temperature should range between 65 and 75 degrees Fahrenheit during the day. A nighttime temperature of 55 to 65 degrees Fahrenheit is ideal.
5. 5. Keep your Boston fern in a partially sunny spot indoors. Indirect light in the morning from a western exposure will help the fronds stay green, while excessive light can cause the leaves to burn. Keep your plant at room temperature (roughly 65 to 75 degrees Fahrenheit) and away from drafty windows.

Maintaining a healthy Boston fern requires a little effort from you as the grower. Keep your Boston ferns beautiful with a few key tips.

1. 1. Consider investing in a humidifier. Boston ferns do best in high humidity levels. If you are growing Boston ferns indoors and the air is dry, a humidifier may help your plants thrive.
2. 2. Avoid overwatering your fern. Watering frequently is important to keep the soil moist, but strike a balance between parched and drenched. Misting your plants on occasion rather than giving a full watering is one way to find a happy medium. Misting offers the added benefit of maintaining adequate humidity. You may need to water more frequently in the spring and summer seasons and less in the winter and fall.
3. 3. Fertilize your Boston fern. Just as your Boston ferns require the right amount of water, they also require a certain amount of houseplant fertilizer. Feed your fern with a liquid houseplant fertilizer every couple of months during the growing seasons, and then skip these feedings in the winter.
4. 4. Prune dead leaves regularly. Snip off any discolored or dead leaves with a clean pair of scissors. Not only will your Boston fern look better, but pruning will also encourage fresh frond growth.
5. 5. Use neem oil to deter pests. Keep mealybugs and spider mites away from your ferns by using a natural insect repellent like neem oil.
6. 6. Repot your plants as necessary. If you notice the growth rate of your fern beginning to slow or the roots becoming exposed, repotting may be necessary. Aim to repot your Boston fern in the spring.
7. 7. Propagate your Boston fern. Divide and propagate your ferns when you repot them during the spring.

Grow your own garden with Ron Finley, the self-described "Gangster Gardener." Get the MasterClass Annual Membership and learn how to cultivate fresh herbs and vegetables, keep your house plants alive, and use compost to make your community—and the world—a better place.