Phoeocoros grows as winter annuals. In the south it can be found growing along moist roadside cuts, eroded areas, and in unplowed fields. In the north they occur later in the season. May. The name hornwort refers to the long thin sporophyte which is embedded in the top of the plant. In hornworts the sporophyte continues to grow throughout its life, unlike most other bryophytes.
Hornworts are gametophyte dominant.
Archegonia and antherida occur on the same plant. The sex organs are in rows. As the antherida mature, the cells of the antheridial cavity break down allowing water to enter, ultimately releasing large numbers of biflagelate sperms. The sperm cells swim to the archegonia where the egg is fertilized. Zygotes, scattered over the plant, grow into new generation sporophytes.