Daniel Gill, Merrill, Thomas A. | 3/31/2007 12:29:00 AM
By Dan Gill
LSU AgCenter Horticulturist
I don’t know about you, but as the hot weather of summer arrives I’d much rather work in shady gardens than sunny ones.
I’ve heard gardening in the shade called challenging, but it’s really no different than gardening in the sun. When the proper plants are selected for shady areas the results can be beautiful and durable.
Lots of great plants for shady areas can be found among the ferns. The different species range in size from under a foot to as much as 3 feet.
The leaves of ferns are called fronds and provide the primary ornamental feature of the plants. On ferns that are commonly used in landscaping, the fronds generally are finely divided and delicate in appearance. They contrast beautifully with coarser-textured shade plants such as hostas, aspidistra, fatsia, gingers and aucuba – although holly fern is an exception, since its fronds are coarser than most ferns and give this plant an almost shrubby look.
Ferns do not produce colorful flowers. Their attributes are more subtle, but no less beautiful, to the discerning eye. It would be unfair to say that ferns are just green. They come in many shades from chartreuse to deep olive, and some produce fronds that are tinted with red or have silvery variegations. Ferns often possess a grace of form and movement that is unique among garden plants (except for maybe ornamental grasses).
Some of the ferns we can plant in the landscape are evergreen, and some are deciduous. Deciduous ferns such as the wood fern (Thelypteris kunthii) and royal fern (Osmunda regalis) lose their fronds in the winter and go dormant. Some of the evergreen ferns also may suffer damage or loss of their fronds during severe winters, but more often they retain their foliage throughout the winter season. If they are frozen back, they reliably return from their roots.
One of my favorite things about ferns is that they are so easy to grow. Generally not prone to any major insect or disease problems, ferns are plants you ordinarily can make happy with minimal care.
Ferns will grow best in areas that receive one to four hours of direct sun or dappled light during the day. Morning sun is greatly preferred. Definitely avoid hot, dry areas that receive several hours of direct sun in the afternoon or areas that receive sun all day. If you want a fern-like plant for sunnier areas, you could plant yarrow (Achillea millefolium) or asparagus fern (Asparagus densiflorus ‘Sprengeri’, which is not a true fern).
The majority of ferns do best in a consistently moist soil. They thrive in our state because of our high rainfall and humidity. Of course, during dry periods you will need to water your landscape ferns. As with all plants, there is no timetable or schedule that you should follow for watering. Watering is done when the plants need the moisture based on the amount of rainfall that has occurred and how hot it is. Mulching a fern planting with your favorite mulch, such as leaves, dry grass clippings or pine straw, is highly recommended to conserve soil moisture and reduce weeds.
When preparing a planting site for ferns, thoroughly turn the soil and remove any weeds. Spread a 2-inch to 3-inch layer of organic matter (compost, rotted manure or peat moss) over the area and dig it in. Make sure it is well blended with the soil in the bed.
Shady areas often occur under trees, and it is entirely permissible to create planted areas under trees that incorporate ferns and other shade-loving herbaceous perennials, ground covers and shrubs. The only necessities are to respect the root system of the tree and to minimize damage to it when you take this route. Avoid adding more than 2 inches or 3 inches of fill to the area around the tree and be careful not to sever any roots over an inch in diameter. When turning the soil, use a turning fork, since it will be less damaging to roots than the blade of a shovel or spade.
Once you have ferns in place, February or early March is the time to cut back the dead fronds of deciduous ferns and to prune away any cold damage done to evergreen ferns. Get this done before the new fronds grow up into the dead ones, and it will be easier not having to work around the new growth.
As time goes by many ferns will grow into a fairly large clump. Should you need to divide your ferns, the best time is in late winter or early spring, around February. Ideally, ferns should be divided before the new spring fronds have made much growth. Once you’ve divided some out, keep them well watered while they get reestablished.
Most nurseries carry a nice selection of ferns. When visiting a nursery, ask where their shade area is, and that’s generally where you will find the ferns along other plants that like the shade and make good companions for the ferns.
Some excellent ferns for use in the landscape include Southern maidenhair fern (Adiantum capillus-vernis), holly fern (Cyrtominum falcatum), leatherleaf fern (Rumohra adiantiformis), Christmas fern (Polystichum acrostichoides), royal fern (Osmunda regalis), autumn fern (Dryopteris erythrosora, known for its coppery red new fronds), lady fern (Athyrium filix-femina), wood fern (Thelypteris kunthii), lace fern (Microlepia strigosa), Japanese painted fern (Athyrium niponicum 'Pictum') and sensitive fern (Onoclea sensibilis).
Get It Growing is a weekly feature on home lawn and garden topics prepared by experts in the LSU AgCenter. For more information on such topics, contact your parish LSU AgCenter Extension office or visit our Web site at www.lsuagcenter.com. A wide range of publications and a variety of other resources are available.