Ferns in the garden
There are many exotic ferns that will happily grow in the garden. Many indoor and glasshouse ferns are also glad to spend the summer months in the garden. This benefits the fern in reducing insect pests and in producing strong growth in natural daylight. You can also keep ferns outside in pots. This makes it easy, if necessary, to give them winter protection or allow them to be brought indoors as frosts approach. And of course, all these can be used together with our native and temperate ferns to create an attractive and unusual exotic display.
1
Position
Most exotic ferns outside require dappled shade or protection from direct sunlight during the hottest hours of the day. This is particularly the case when they are first planted out, as the fronds may be burnt, particularly if they have been previously grown in darker conditions. As a general rule, do not put them in windy places as they will dry out very quickly.
2
Watering
Most ferns need to be kept moist but not wet. Rainwater is the best water to use. In times of drought, any water is better than no water, and you may have to resort to using the mains supply. Keep the watering routine simple, especially if you need help when you are away from home. Some exotic ferns that are planted out do not tolerate winter wet and should have protection from rain during the cold weather.
3
Soil
For exotic ferns planted out in the garden, ensure that the soil is free-draining and not waterlogged in the winter months. Beds can be prepared by digging in plenty of composted bark. The best compost for ferns in pots is light, moisture-retentive, and free-draining. Use a good-quality bark-based, peat-free compost and mix in some loam and some grit.
Choice Ferns
Many exotic ferns can be incorporated into your garden. Although they come from tropical and subtropical parts of the world, many suitable ferns actually originate in cooler, higher-altitude regions, making them ideal for growing in temperate climates. Most of this selection are readily available in the trade and will grow happily alongside our native ferns and with other perennials.
Autumn Fern
Dryopteris erythrosora
This fern keeps its shiny green fronds all year round. In the spring, new growth is an attractive orange or bronze colour. It is very tolerant of irregular watering and will grow in shade.
Chilean Hard Fern
Parablechnum cordatum
Often sold as Blechnum chilense. It is not unusual for this fern to have fronds of almost one metre in length. It is statuesque and unusual. It can be damaged by heavy snowfall breaking the fronds but is otherwise very tough.
Woolly Lip Fern
Myriopteris tomentosa
Often sold as Cheilanthes lanosa. This silvery-grey fern looks fantastic in a rockery or well-drained site. It is only 20–25 cm tall, so needs to be near the front of a display. It needs protection from winter wet to prevent rot.
Himalayan Maidenhair Fern
Adiantum tibeticum
Sold as Adiantum venustum, this hardy Maidenhair Fern will grow outdoors beneath shrubs and trees. New growth is rust-coloured and about 20 cm tall. It is easily broken and should be planted where it will not be disturbed.
Hammock Fern
Blechnum appendiculatum
This fern has pink new growth that fades to green as it matures. In the garden, it is deciduous in the winter but returns in late spring. It needs a sheltered site but no special winter protection.
Felt Fern
Pyrrosia lingua
There are many varieties of this fern with variegation or irregular frond edges. It comes from Japan and is tolerant of light frost but not winter wet. It will slowly form a clump of tongue-shaped felty fronds about 25 cm high.
Caring for your ferns in your garden.
As a general rule, most garden ferns prefer to be planted in areas of the garden that are shady and where the soil has some moisture but is not waterlogged. Of course, there are exceptions to this, with some ‘xeric’ ferns preferring rock garden conditions and some ferns, such as Woodwardia, needing quite wet soil. Borderline-hardy species and tree ferns will require some degree of winter protection from frost and heavy snowfall. Always do some research before planting out a fern. Ferns tend to be fairly pest- and problem-free in the garden if their environmental needs are met.
​
If you do have drier areas of the garden where you want to grow ferns, there are certain species that may suit these conditions, for example, Dryopteris erythrosora. There are also many native and temperate foreign ferns that will give you an exotic effect. These ferns will require regular watering and shading from direct sun whilst they become established and develop a root system. Extra care should be taken for their first year of planting.
​
Ferns like their growing conditions to be consistent. As a general rule, it is not a good idea to move a fern if it has been growing well in a particular location. The frondsʼ physiology will adapt to the specific environmental conditions over time. So, only move established plants if necessary and after you have considered the risks. If you do need to move a fern, itʼs best to do this in mid-spring or early autumn.