Tree fern care

Caring for tree ferns 

Ferns are not usually thought of as garden perennials and yet nature has carpeted her forest floors the world over with ferns. Of the 12 thousand species of ferns in the world, many of them are reliable, hardy garden subjects. Ferns have been popular garden and indoor subjects since the middle of the nineteenth century. Their ethereal beauty and elegance make them desirable for many types of gardens such as exotic tropical, subtropical, shady woodland, native, perennial borders and specialised ferneries. What do ferns like?

To successfully grow ferns, a number of conditions need to be met. 

• Moisture and mulching to maintain moisture 
• Air movement around the plant. 
• Shade – you will be fairly safe with mid to light shade or dappled light. 
• Fertiliser – a light sprinkle of blood and bone in spring. 
• Humidity – make sure there is no constant wind or draughts battering your ferns. These reduce humidity. 
• A well-drained, preferably friable soil. Ferns have a number of conditions they dislike. To grow ferns successfully these should be avoided or minimised at best. 
• Wind 
• Sun – fern species that require shade never do well in the sun and rarely recover to their full potential once exposed 
• Sour, soggy soil – most fern species grow best in friable, well drained, moist soil. 
• Cold weather -slows down their growth. Many are frost tender. 
• Pests 
• Diseases Ferns – a background Ferns belong to a large ancient group of woody herbacious plants called Pteriodophyta. These evolved around 600 million years ago when the ancestors of ferns covered large areas of the earth in huge forests. There remain around 12 thousand fern species worldwide. Most of these species grow in tropical, or sub-tropical climates and very few, if any, are to be found in extremely arid or cold areas. Ferns evolved before there were any insects or birds to pollinate them and they have devised a clever way to procreate. They use water to aid reproduction and this is probably why most ferns like to grow in damp places.

What should I look for when buying a fern? 

• A healthy undamaged crown of new fronds 
• A disease free plant with no blotchiness on the fronds 
• A pest free plant with no scale, aphids or mealy bug 
• A well developed root system. The plant should be robust, not loose in its container. 
• A good shape – especially important if you choose to buy ferns that have been dug out of the pine forests. 
• Superba ferns list 
• Ferns for 
• Sunny, mulched positions 
• Coastal conditions 
• Moist shady positions 
• Dry shade 
• Light shade

Tips on Caring for Your Ferns

Planting your ferns

You should plant most species of fern in friable, well drained soil. Make sure the soil is not soggy or poorly drained. Mulching will help the drainage and condition of your soil over time. If you have a clay pan, condition the soil to break up the clay or your site will be too wet. 

If you have light, friable soil, your task is relatively easy. Make a hole slightly larger than the size of the fern container, add a little bit of compost to the bottom of the hole, place the plant in and fill around the fern with soil. On the other hand , if your soil is heavy or clay, you will need to dig a hole that is twice the size of the container the fern is in. Line the hole with compost and even small stones to improve the drainage and condition of the soil around the plant. Once you have placed the fern, mix the soil with compost to fill in the hole. If your soil is particularly heavy, you may need to dig small channels radiating out from the hole to drain the soil. These steps are especially important if you are planting tree ferns. 

Once planted, sprinkle a tiny top dressing of blood and bone to help establish your fern. 

In general, select a site that has partial shade or dappled light unless the fern particularly needs more sun. Most ferns do not like heavy shade. Your situation should also be protected from the wind. 

Do not plant your ferns too deeply – make sure the crown is not covered or your fern will develop crown rot. 

How do I look after my ferns over winter?

This is a frequently asked question, especially if your garden catches the odd frost. 

Here are some helpful suggestions. 

When a frost is forecast or you feel it in the air, take precautions with your ferns. Use frost cover or newspapers laid over the fronds to protect them overnight. This is especially important with your young tree ferns. 

Ferns specifically marked ‘Cold hardy’ are better to plant during this time and will endure the winter relatively easily. Ferns tend to be dormant over this period so make sure you do not overwater them. If you have overwatered your ferns, the fronds will start to go brown or even black in patches. If it is not too late ie there is still a healthy crown, stop watering! Your ferns get enough water from the rain – you should not need to water them over winter. 

Some ferns such as Matteucia strutheopteris,Athyrium otophorum and Adiatum aethiopicum are deciduous. They will turn yellow and die down at the onset of winter. Don’t panic – they will surprise you with a new flush in spring. 

and in the summer… 

We recommend mulching around your ferns in summer. They should be given a good soak at root level at least once a week rather than using a misting system. Be careful not to overwater your ferns during this time. 

Summer is the time that many pests strike. Ferns are sensitive to sprays so we recommend half strength Orthene or Pyrethum. If thrips are a problem, you may need to take drastic action by cutting back the fern and disposing of the infected fronds.