There are nearly 10,000 species of ferns. Florida alone has one-third of all fern species in North America. Our warm and moist climate provides an excellent tropical habitat for these unique foliage plants.
Ferns should be planted in a mixture that drains well. It is the primary growing consideration besides watering. A peat (60%) and styrofoam pellets (40%) make a good mix. This can be amended with some sand (for weight). A soil-less mix is also a good medium. Staghorns can be plaqued, placed in trees or wooden baskets. Spaghnum moss or osmunda fiber are ideal mediums when used in wire, wooden baskets or plaques. Ferns should be planted with the crown of the plant sitting above the soil line.
Moisture is the key to good fern growth. The medium in which the fern is growing should at all times be a least slightly moist. Moist does not mean wet. A wet soil will not allow the roots of the plant to breathe. A porous mix will provide the necessary drainage and subsequent vital aeration. Water in the morning so the plant can dry out before evening. This will help in disease control.
Fern roots must always have a constant supply of air as well as the top of the plant. Roots need oxygen in order to maintain their proper health. A porous mix and proper spacing will help provide the air movement they need.
Most fern plants are adapted to absorbing tiny amount of nutrients from slowly decomposing organic matter in forest soils. These nutrients are made available to the fern roots through the soil water after being released by some biological activity. This biological activity usually involves soil microorganisms such as fungi, bacteria, worms and insects. This microbiological activity, which is present in all healthy forest soils, provides a small but continuous supply of nutrients to the fern plant. We can add fertilizers to the soil to help but not destroy this soil ecology by using slow acting materials such as a slow release fertilizer.
When purchasing fertilizer look for a well balanced one containing the proper nutrients (nitrogen, phosphorous & potassium) plus minor elements (vitamins). There are good slow release as well as water soluble 20-20-20 fertilizers available. Care should be exercised in providing food that will not burn the roots. Soluble slats from some fertilizers can cause serious damage to your ferns. Each month thoroughly drench your ferns with plant water to help remove any fertilizer salts that have accumulated. Palm Hammock has several recommended fertilizer mixes available.
No fern will do well in dark shade. Ferns need at 50% of the available outside light. 2' wooden slats spaced at 2" intervals oriented north and south will provide this. Some shade trees (oak, mahogany, gumbo limbo, etc.) also provide adequate shade. Two hours of full sun before (;00 a.m. or after 4:00 p.m. would be helpful. Some ferns will grow well in full sun; however, most ferns look their best in some degree of shade.
Biological responses are directly related to temperature. The higher the temperature the faster these biological reactions take place, hence the warmer weather of summer will usually cause faster plant growth. Ås temperatures rise past the 90 degree mark during the day or 80 degrees at night, most plants will show poor growth response. Increased watering and feeding will alleviate this condition to various degrees, depending upon species. Generally ferns like temperatures from 70 degrees to t0 75 degrees. Most ferns can withstand low temperatures to freezing without damage and we will rarely have cold damage on ferns commonly grown in South Florida.
Courtesy of: Palm Hammock Orchid Estate - 9995 S.W. 66 St. - Miami, Fl 33173 (305) 274-9813 www.palmhammock.com