A wide range of ferns as well as a number of other plants are suitable for growing in dry shade, by dry shade we mean deciduous shade or evergreen with a lifted canopy. Ferns planted underneath leylandii in dust dry conditions are unlikely to survive.
The majority of ferns are forms of native species, they seem much better adapted to British weather conditions. Male ferns are often found in the driest part of our deciduous woodlands.
There are both evergreen and deciduous species suited to dry shade, and a wide range of size of eventual growth height or width, from 15cm to 1m tall.
Ferns suitable for dry shade.
Asplenium scolopendrium The native harts’ tongue fern is easily grown in alkaline heavy soil in dry conditions. Strapped shaped fronds it is evergreen and to around 45cm tall and wide. Commonly grown in the cultivars ‘Cristata’ with a crest at the end of the frond, ‘Fimbriata’ in which the frond is slight narrowed and cut sided.
Dryopteris affinis AGM The native golden scale fern is easily grown, it is tolerant of both acid and alkaline soils and grows to around 80cm tall. Quite upright in growth it is semi evergreen, remaining green till very early Spring then flopping and refronding in April. Commonly grown in the cultivars
Dr. a. ‘Cristata The King’ AGM crested form, a vigorous easy plant. D. a. ‘Pinderi’ Upright shuttlecock shape. D. a ‘Polydactyla’ Pinnae slightly reduced and flared into a fish tail end.
Dryopteris filix-mas AGM The common male fern of British woods and ditches. To around 60cm tall, totally deciduous it will die down after the first hard frost. Probably the most tolerant of very dry soils in the cultivar ‘Linearis Polydactyla’ or ‘Depauperata’, other commonly grown cultivars include the short (30cm tall) ‘Crispa Cristata’ with crisped as well as crested fronds. ‘Cristata’ A variable form with crests from quite small to large and heavy easily grown.
Polystichum aculeatum AGM The native hard shield fern, evergreen to around 30cm tall and 60cm wide it is easy and very tolerant fern for dry shade. Dark green in colour the pinnae are only once cut and quite bold. For some reason cultivars are very rare.
, evergreen to around 30cm tall and 60cm wide it is easy and very tolerant fern for dry shade. Dark green in colour the pinnae are only once cut and quite bold. Cultivars for some reason are very rare.
Polystichum setiferum AGM The soft shield fern another native and probably the most variable of ferns found in these lands. The base species is some 80cm by up to 1m wide and again variable. It is evergreen and very tolerant of dry soils. Commonly grown cultivars include ‘Acutilobum’ Pinnules terminate in a narrow point, quite frequently proliferous (see propagation) an elegant fern. ‘Divisilobum’ Tends to grow flat with pinnules cut and divided up to three times. Can form a spiral shape with the large fronds curling around. ‘Plumoso-multilobum’ (syn ‘Plumoso-densum’) Heavily overlapped and dense fronds almost moss like, very attractive fern to 60cm across.
Polypodium vulgare and cambricum Two low growing creeping species very tolerant of dry soils, P. cambricum is Summer dormant while P. vulgare is evergreen. To around 30 tall they spread to form a patch with creeping rhizomes. P. vulgare ‘Bifidomultifidum’ is the most commonly available cultivar, with a broad crest terminating the frond.
How to buy ferns suitable for dry shade.
They are available, with the largest range coming from specialist nurseries. You will also be able to get the most reliable advice from these nurseries, garden centres particularly have a very poor knowledge of the different growing conditions for the various species. Ferns purchased in 1l pots will quickly make up into good sized plants. It is best to avoid planting in either mid summer or mid winter but plants put in late Spring will need watering through the Summer to establish. The best time of all is early Autumn but this has rather fallen out of fashion recently.
In small numbers fern can be divided separating them out into individual crowns or removing pieces of rhizomes in Polypodium. Proliferous form of Polystichum setiferum can be propagated by pinning sections of frond down onto some compost and keeping in a close atmosphere, such as a frame or under polythene or a sheet of glass over winter, in spring the buds will grow away and can be separated