Boston Fern


A Boston fern (Nephrolepis exalta) is native to tropical forests and swamp areas around the world. These ferns are especially prevalent in Florida, Mexico, Africa, Central and South America, and Polynesia. Indoor ferns are not that difficult to grow, but they cannot be ignored and are not as forgiving as some other houseplants. High humidity and keeping the soil barely moist are two keys to success. In addition to the Boston fern, the easiest ferns to grow indoors are the Kimberly Queen fern, the Rabbit’s Foot fern, and the Bird’s Nest fern.

Boston Fern Description

The wide- spreading Boston fern, with its long, arching fronds looks beautiful in hanging baskets. The fronds or leaves can be 2-3 feet long and 4-6 inches wide. Each frond has small leaflets (pinnae) on either side of a midrib. The leaflets have slightly serrated edges and a deltoid shape.


Other ferns that belong to the Nephrolepis family and resemble the Boston fern are:

Fluffy Ruffle Fern or Feather Fern that has leathery leaflets with ruffled edges arranged in a double herringbone pattern.

Lace Fern has lacy leaflets arranged in a triple herringbone pattern.

Kimberly Queen Fern or Australian Sword Fern is more compact and neater than a Boston fern, and has erect, narrow, sword- shaped fronds.

                   Kimberly Queen fern, Australian Sword fern, has long, almost erect, sword-shaped, green fronds

Lace Fern                  Fluffy Ruffle Fern          Kimberly Queen Fern

Boston Fern Problems

The special special problems that a Boston fern, and other indoor ferns have, are easily solved if you know what is causing them.

  1. Brown dots on the back side of the fronds: This is not a sign of a disease or plant pest. The brown dots are spores that appear when a fern is mature and healthy. In commercial greenhouses they are used for propagationLearn how to propagate plants by plant division at
  2. Pale fronds can be an indication of several things. The fern needs to be watered. It is getting too much bright lightVery few houseplants should be placed in direct sun. High light refers only to bright indirect light since direct sun often burns the leaves of indoor houseplants. An area that is too hot and dry encourages Spider Mites and causes blooms to quickly fade. A northern exposure really doesn't provide enough light for high light plants. These plants need to be placed directly in front of an east-facing window, within 1-3 feet of a west-facing window, and within 5 ft. of a south facing window. A high light area has over 300 ft. candles of light.. The plant needs more fertilizerPlants need fertilizer only when they are actively growing. Slow growing plants in low light require very little plant food. Too much fertilizer is worse than not enough. Most plants prefer a water soluble plant food at 1/2 the recommended strength. Plants that are in bloom or dormant should not be fertilized. Houseplant food contains nitrogen (N), phosphorus (P), and potassium (K). A fertilizer containing these elements in equal proportion is considered a balanced plant food. Nitrogen helps in photosynthesis and encourages the growth of leaves and stems. Potassium and phosphorus also help in photosynthesis and aid in root and flower development. Most fertilizers have trace elements of other minerals that are lacking in the soil but are necessary for good plant growth. Fertilizers have a high salt content. If a plant is not producing new leaves and doesn’t absorb the fertilizer, salts build up in the soil. These salts can burn the roots, discolor the leaves, and cause new growth to be small..
  3. Brown tips and fronds turning yellow indicate lack of sufficient humidity.
  4. Yellow, limp leaves, and rotting stems are caused by too much water and are signs of root damage.
  5. Crispy leaves tell you the plant needs more water.
  6. Tiny, brown shells appearing on the fronds are caused by the plant pest “scale.” Do not confuse scale with harmless spores.


A Boston fern is a clean air plant and helps remove removing formaldehyde from the air. It loves to vacation outside in the shade when the weather is warm but not too hot. Remember to bring it indoors before nighttime temperatures go below 50°F (10°C). A Boston fern is a non-poisonous plant safe to have around small children, cats, dogs, and other pets.



Can I Set My Boston Fern on Top of a Refrigerator in My Very Bright Kitchen?

Ferns do best when the temperature is cool (60°-70°F). The top of a refrigerator is not a good place because it gets too hot.

Why Are the Ends of the Leaves on My Boston Fern From Turning Brown?

The tips of the fronds or leaves on a Boston Fern, and other ferns, may turn brown for several reasons: There is not enough humidity the air. The water you are using contains too much chlorine or fluoride. You are using water that has passed through a softener and is too salty. You are over feeding the plant and the salt in the excess plant food is burning the plant.

What Is the White Sticky Stuff on the Fronds of My Boston Fern? I’m Guessing It’s Mealy Bugs. If It Is, Can I Spray Alcohol on My Fern to Get Rid of Them?

It sounds like you Boston fern has Mealy Bugs. However, since the fronds of a Boston fern are delicate, you have to be careful what you spray on the plant to get rid of the Mealy Bugs. Spray your Boston Fern with warm soapy water or diluted insecticidal soap to get rid of Mealy Bugs. You may have to spray the plant several times to completely get rid of the problem.