Primitive Ferns and Fern Oddities

From The Encyclopaedia of Ferns An Introduction to Ferns, their Structure, Biology, Economic Importance, Cultivation and Propagation by David L. Jones ISBN 0 88192 054 1:-

"Genera Angiopteris, Botrrychium, Christensenia, Danaea, Helminthostachys, Marattia, Ophioglossum, Osmunda and Todea are a loosely related group of ferns which have primitive features. Some have dimorphic fronds or specialized fertile blades attached to sterile blades of vastly different appearance. In size, they range from tiny plants with fronds a few inches long to giants with fronds several yards in length. With the possible exception of species of Osmunda, few ferns in this group are commonly grown and lack commercial appeal.

Habitat
These ferns mostly occur in moist conditions, particularly in situations where the soils are moist to wet. Species of Angiopteris, Marattia and Danaea generally seek sheltered, shady situations while most of the others grow in more open conditions. Species of Botrychium, Helminthostachys and the terrestrial Ophioglossum are deciduous and die back to a perennial root system each year. Some species of Osmunda may also be deciduous though the others are evergreen.

Cultivation

Uses
Ferns of this group are mainly grown by collectors for their interest value. Large plants of Angiopteris are impressive and can be the focal point of a planting. Species of Osmunda are very decorative and lend themselves well to landscping where water is a feature. Todea barbara is an impressive fern which makes a very durable container plant. Ophioglossum pendulum is unsurpassed as a basket plant. Species of Botrychium can be difficult to maintain and may succed best in a garden situation.

Soil Types
Most ferns of this group will tolerate quite moist to wet soils, preferably with the water moving and not stagnant. Species of Botrychium and Ophioglossum like moist but not overwet soils.

Potting Mix
An open mix based on a well-structured loam is usually suitable. Despite their tolerance of moist soils a well-drained potting mix is necessary. Most species seem to need soils of an acid pH.

Watering
Ferns of this group like plenty of water and may suffer sever setbacks if allowed to dry out. Plants of Helminthotachys and the terrestrial species of Ophioglossum appreciate having the base of the pot submerged in a container of water while they are in active growth.

Fertilizing
Species of Botrychium, Helminthostachys and Ophioglossum require little in the way of nutrients and occasional applications of old manure or weak liquid fertilizers are adequate for their requirements. The other ferns will respond to applications of manures or fertilizers but are generally not heavy feeders.

Situation
Species of Angiopteris, Christensenia, Danaea and Marattia prefer shady conditions and have their best appearance when provided with such protection. The rest of this group needs bright light and will happily grow in the sun if the soils are moist to wet. Many of the tropical species are sensitive to cold, especially frosts.

Pests
Slugs and snails may be very damaging to the fleshy fronds and rhizomes of many of the ferns included in this group. For plants of Botrychium and Ophioglossum continual protection may be necessary " (See Pest Control by companion planting).