Ferns may fairly be characterized, looking at them in a general way, as rock plants; for there are very few indeed of the known species that cannot be successfully grown on or between the crevices of rocks. Hence, under cultivation, what is called rockery - little eminences, built up irregularly in a pile of any shape, and consisting of a conglomerated mass of earth and stones - affords the best means of arranging these plants, so as to display to the greatest advantage their elegant and graceful forms, and the best means also of accommodating the conditions of culture to their natural requirements. Of all the various methods, too, of growing ferns, that of growing them on "rockery" is perhaps the most popular. It is certainly a method which admits of the widest possible adoption; for, as in the most extensive grounds there is the widest scope for the creation of rockery on a large scale, so, on the other hand, there is no bit of garden so small, and no tiny strip of courtyard so limited, as to preclude altogether the possibility of introducing some little grouping together of rocks in association with at least some graceful ferny forms.

Rockery may fill up the entire area of a large space, or it may be used conveniently to supplement any existing garden devoted to flowering plants; to fill up, in fact, in such a garden the damp and shady corners which lie beyond the borders of the flower world, because the brilliant inhabitants of that world cannot live without the genial influence of sunshine. But ferns court shady corners, rejoice in quiet gloom, and gladly occupy the places shunned by the gayer inhabitants of the sunny regions. - The Fern World, by Francis George Heath.