Everybody who grows orchids has their own theory, and formulas for what to feed orchids, but the general consensus for one like yours with little or no medium around the roots is to spray regularly with a water-soluble fertilizer formulated specifically for orchids. Orchid formulas have the nitrogen component in a soluble form more readily available to epiphytes than regular fert where most of the nitrogen is in the form of urea.
Short answer, a little box or bag of fert labeled specifically for orchids is what you want. I use the Better-Gro Orchid Plus, available at HD or Lowe's. A little bag lasts me nearly a year (and I have 70 orchids, give or take). It works great on bromeliads and other epiphytes, too. My pitcher plant really likes it.
Since you're in Florida and your orchid is living outdoors, a couple of other things to consider - better throw a towel or blanket over it if the weather gets cold. Below about 45 will stress it quite a bit, and into the 30's could be deadly. In your Aunt's garden it was possibly more protected in the shadier spot. (or she may have covered it, too).
I ease back on watering and also fertilizer when the weather cools off. This weather we've had lately is perfect orchid weather, so I am misting mine every day, alternating plain water (rainwater if there is any in the rain barrels is best) and fertilizer water. As it gets cooler, I might skip a day, and only mist with the fert solution twice a week. As it heats up, and through summer heat I mist every day with the fert solution, unless it rains. Higher temps stimulate more growth.
These are just rules of thumb, not hard and fast things you "must" do. I try to think of what this orchid would have lived on in it's natural habitat, and try to let it live like that. They get nutrients from the air and from what falls from the trees above etc. Only if you give it more regular feeding and water you will get healthier growth and more blooms than it would have had in the wild.
Thanks so much dyzzy, I really appreciate your help. I have four other orchids and need to take better care, they were given to me as gifts last year. I already lost one from too much sun exposure.
I will bring the orchids inside the Florida room if we dip below 40. Which hopefully doesn't happen, so far so good.
You would need to know what kind of Dendrobium it is to know how to take care of it. They grow in many parts of the world and in many habitats. It is a Dendrobium but Dendrobiums are currently the third largest genus of orchids with somewhere between one and two thousand species and many more thousands of hybrids. It looks like this might be a Dendrobium nobile type. These orchids like to be dry in winter and should only be misted several times a week, but rarely watered. Just enough to keep the canes from shriveling. All fertilizer should be held until you see new growth emerging. They otherwise don't like much fertilizer at all. If your orchid starts producing new canes instead of flowers mid-Winter/Spring it is because (1) you watered the plant when it should be resting, (2) you kept the plant too warm (they happily enjoy temperatures in the forties and high thirties), (3) you fertilized the plant and forced it to grow out of season. Fertilizer is not a substitute for good culture. In other words, it won't fix a problem or make flowers. It only makes better plants and, arguably, more flowers. If this was my orchid I'd not consider fertilizing until you see signs of new growth. If it has been outdoors and receiving the benefits of rain I'd leave it alone. If the temps are going down below high thirties bring it in. My cool Dendrobiums are all out right now and we are forties every night.
Thanks Maypop...yes after my research it is a D. nobile type. I have it outside for now, gets very early morn and late afternoon sun. We haven't had much rain at all and no nights below 40 yet. Looks pretty happy right now, but I'll be sure to bring it in if dips below 40. I do appreciate the info...it is nice to know what it is so I can do my research, but a lot is for raising in green houses and not for outdoor tropical climate, so it is appreciated to have advice from those that raise them outdoors.
I'm sure my aunt used to bring it in, but the last year of her life I'm sure it just endured the elements outdoors...thank goodness we had a warm winter last year.
We had a spritz of rain when Sandy went by, and maybe one more shower in November, but my rain barrels and cisterns are empty now.
But I'm afraid to wish for rain, because that would mean a cold front, and the end to this perfect weather we've had. The orchids are just growing and blooming so perfectly. Highs of 80, lows of 60, moderate humidity, could it possibly be better?
tommy you should post some pictures of your plants.
Elaine, I am so enjoying not having to cover and drag in plants, I keep looking at the future weather outlook and so far so good. We had a nice little bit of rain a few days ago and fog the last two days with enough humidity to wet everything. I was actually walking around the garden yesterday thinking I need to cut some things back, but I know as soon as I do we'd get a cold front and I'd wish I hadn't ...looking like a jungle out there. ☺
My bleeding heart vine taking over the shed and now my hammock too. Last winter is the first in a few years it did not totally freeze back to the ground.
Thanks Breeindy for posting the photos, I see little nubs starting under the leaves on mine. I'm having to put it in my temp green house on these real cool nights, but so far it is looking good. Another cold night tonight looks like.
I forgot to post my Dendrobium nobile orchid that you all helped me ID once it finally flowered. It was so spectacular and just now has the flowers finally faded, gave me a good five plus weeks of flowers.
Thank you once again for helping me ID my Aunt's orchid.
Those flowers are darling.
I have 4 Dens & none have ever rebloomed. They look happy and have plenty of new growth, just never bloom. I can't even remember what they ever looked like in flower & the tags have long ago disappeared or faded.
I'm sure this plant had no fertilizer for years. My Aunt was 93 when she passed away and I the plant was very dried up to nothing. I haven't put any fertilizer on it since I've had it either. I almost didn't take it from her carport thinking it was dead.
I did read that they can take much cooler temps than most orchids and even a light frost, it helps to encourage blooms. So I left it out even when we dipped to 38 degrees, anything under that I put it in my makeshift green house. It gets bright sun real early and real late in the day, then filtered and shade the rest of the day. I obtained it in late August and it started looking better when we were getting afternoon rain showers. The buds started as soon as nights were dipping into the 50's.