A beautiful, small native fern, very rare in cultivation. These are spore grown plants and, like all of our plants, not taken from the wild!
Evergreen, frond length to 12cm.
Fronds green on top, a rust red underneath on mature plants. Seen growing in old walls and limestone areas. They like plenty of sun and a lower humidity than many other ferns. If they dry out after a dry spell the fronds soon rehydrate after wetting.
Not the easiest fern to grow, should be treated like an alpine and grown in calcareous, very well drained, soil or in a living wall (some old mortar inserted into the soil will help. Tolerant of drought once established but don't allow to dry out when young, keep the compost just moist.
Now you know why it is rare in cultivation!
Asplenium ceterach (Rusty Back Fern)