Answer: Your Elk fern is also called a staghorn fern. To attach a stag to a board, you'll need a board, some sphagnum moss and some fishing line. Prepare some sphagnum moss by soaking the moss in water (rain water is best) for several hours to hydrate the material.
The mounting board you select should be a hard wood, like oak or mahogany, and as large and thick as you like. You could also use pecky cypress or redwood. Your stag will grow sideways so the larger the board you start with, the longer your stag can remain growing undisturbed.
On the back of your board, attach a very strong hook or wire loop or steel chain to support your stag when hanging. This must be very strong because your stag will get very heavy in the future. Use strong screws versus nails.
On the front (mounting) side of your board, tack in small nails in a pattern an inch or two larger than your stag. Now place some of your soaked sphagnum moss in the center of the nails (the center of your board). Lay your stag down onto the moss with the fertile frond tips up...the same direction as your mounting hook.
Get some light see-through fishing line, say 5-pound test line. Tie one end of the fishing line to one of your nails. Cross over the stag to the opposite nail. Keep crossing your stag with fishing line and attaching to your nails until your stag is firmly mounted.
NOTE: As your stag grows, it will grow over the mounting fishing line and therefore disappear from view.
You will disturb your stag a little in doing this, especially you will wipe off some of its protective "fuzz" that looks like fine white hairs. Try to limit this wipe-off damage as much as possible.
If you have a small stag, you could also use strips of panty hose instead of the fishing line. The advantage of the panty hose is they will disintegrate in about a year. At that point your stag should be nicely attached to your board.
You now must select a location to hang your stag. Outdoors is best, of course, but if you live in a cold winter area, you'll want to keep your plant indoors.
Bright light but no direct sun is ideal. Your stag can handle some sun, but early morning sun only. In the wild, they always have a leaf canopy over them producing broken shade...so approximate this condition as best as possible.
Feed you stag with organic food such as fish emulsion fertilizer. Another good trick is to place a banana peel (peel only) behind the stag...between the stag and the board. They like the potassium.
Most people over water their stags. Water about once a week and soak the moss to do so. The water will pour through quickly so you'll have to apply a lot of water to get a little wetness in the moss...if you have let it dry out too much. If you keep the moss moderately moist, this will not be a problem. Again, water with rain water if possible.
MORE STAGHORN FERN INFO:
To re-mount a stag, you can nail or screw the old board onto a new larger board. You could also use a knife to cut down between the board and the moss and dis-mount your stag, then re-mount it on a new board.
You can cut your stag into pieces. As stags grow, they form new individuals each with a sterile frond at the center with fertile fronds protruding. Use a knife to cut individuals off a mother plant and re-mount the babies. Some may die but most will live through this surgery.
Indoors, keep your stag out of the way of hot or cold blowing air.
There is no particular care for your staghorn fern except to provide the proper conditions as explained above.
Outdoors, leaves and other airborne materials will fall onto the moss backing your staghorn. As these materials decay, they provide added food for your stag.
Most staghorn varieties are very easy to grow. However, some are very difficult and can very easily be killed by fungus, usually via too much water.
If you have a staghorn fern, it is probably Platycerium bifurcatum. Other varieties include grande, willinckii, hillii, coronarium, veitchii, alcicorne and sumbawnse.
Hope this provides all the information you need to grow a staghorn fern.
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