What Are the Tiny Dots on the Underside of a Fern?

Reproduction by Spores

• When ready, the spores in the spore cases will be released by the ferns. Each individual spore that survives will become a sporophyte, which will in turn develop into a small, flat, leaf-like structure known as a prothallium. Both male and female reproductive organs develop on the underside of the prothallium. Once the female organ has been fertilized by the male, the first fronds will appear and eventually develop into a mature fern. This process can take between two and six months for each individual fern.

Reproduction by Division

• A second way that ferns may be reproduced is with the aid of man. Ferns may be split by division to create new plants without reproducing by spores. Every three to five years, a mature fern may be dug up and split into two or more sections to be replanted. Each "new" part will develop into a full plant so long as an adequate amount of root mass was split. This should be done in fall after the first frost, or in early spring before the fern starts to grow again.

Favorable Conditions for Reproduction

• To promote healthy reproduction of your fern, make sure that it has ideal conditions for growth, whether it is an indoor fern or is grown outdoors. Ferns prefer to be grown in moist, humid conditions. Achieve this inside the house by misting occasionally with a spray bottle or by keeping a steady supply of water for evaporation near the fern. Achieve this outdoors by planting ferns near other plants or a water source. Different species of ferns have different light requirements, but in general, ferns prefer indirect light.

Types of Ferns

• All ferns reproduce by spores, but there are four classes of ferns that comprise the thousands of different fern species. Psilotopsida ferns are related to the first vascular plants that evolved, and the only remaining species is the whisk fern. Lycopodiopsidas are a class that includes mosses and quillworts. Horsetails are the only species in the class Equisetopsida. The largest class of ferns, with 12,000 species, is the Polypodiopsida class. Most ferns belong to one of the 300 genera that occur within this class.