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08-07-2022, 08:17 PM
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Jr. Member
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Join Date: Jan 2022
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Black spots on Dracula Citrina
About a month ago, I ordered this Dracula Citrina from Ecuagenera. When it arrived, it had a few black spots scattered on the leaves, but nothing too worrisome. I potted it in a plastic cup with sphagnum moss to acclimate/ keep in humidity. Recently, I have noticed a large amount of tiny black dots all over the plant and browning leaf tips. I believe it is from too high humidity, but wanted input from experienced growers. Any ideas about identification of the problem and treatment for the plant?
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08-08-2022, 12:57 AM
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Super Moderator
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Join Date: Jun 2008
Zone: 10a
Location: Coastal southern California, USA
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My guess is some sort of fungus. The "airless" environment would tend to encourage it. I get similar markings on my Dracs that live outside, so I don't think it's anything that moving fresh air can't control. Take it out of that enclosure - it doesn't need to be THAT humid. It needs air movement. Keep an eye on it, but unless it gets much worse, probably no treatment needed.
From the photos that I found for this one, the flowers are held above the medium, so you don't need to put it in a basket.(The ones that come out of the bottoms of pots need that) So the way that you have it potted should be fine. Your biggest challenge is temperature, this is a high-elevation species. (In habitat, it probably never gets much above 80 deg F, and may get down into the low 40's to mid-30's F in winter) If it's in an air-conditioned house, probably best place this time of year. One possibility might be to use a terracotta pot rather than plastic (with sphagnum) You'll get some evaporative cooling in the root zone that way.
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08-08-2022, 12:57 AM
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Join Date: Jun 2015
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Whenever you ask a growing question we will need to know your growing conditions. Temperature day/night, relative humidity, what kind of light, how strong and what is the daylength, how you are watering and how often, what kind of water, whether fertilizing and what kind, what is the potting medium.
Is it still wrapped in the sphagnum moss it came with from Ecuagenera?
I can almost guarantee high humidity does not cause black spots in Draculas. They come from places where it is almost always extremely humid.
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08-08-2022, 01:11 AM
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Just for the record... I grow all of my Draculas in plastic baskets with sphagnum, as shady as I can manage, outdoors in coastal southern California. So summer days are warm but mostly not too horrible (above 90 or 95 deg F is rare and they put up with it), summer nights in the high 60s to low 70's F. Winter nights stay above freezing but not by a lot. Summer daytime humidity usually around 50%, occasional days of hot winds and single digit humidity, when I just water everything a lot. So if you keep it wet, it will tolerate humidity that is much lower than it gets in habitat. RO water (they do like pure water)
It's a fairly rare climate... OP, how does this compare to yours?
Last edited by Roberta; 08-08-2022 at 01:15 AM..
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08-08-2022, 01:17 AM
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Thank you for the interest. I keep this orchid about 2 feet from a strong grow light, so not extremely bright, for about 15 hours a day. It's inside a house, so temps range from 73-80 degrees during the summer, 65-78 during winter. Ambient humidity is very low, so I kept it in the cups and aired it out once a week, as I researched that Draculas need high humidity. I potted it in fresh sphagnum moss to promote root growth, as it lost most of its roots during transportation. I'm not fertilizing right now, but plan to once more roots grow with RepotMe MSU fertilizer at half strength. I water with tap just enough to keep the moss moist.
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08-08-2022, 01:26 AM
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Air movement is actually more important than trying for high humidity that can grow mold and such, especially stagnant wet air. These don't need strong light, they are low-light plants. 15 hours a day is too much. Near the equator, days and nights are nearly equal. So daylength of 12 hours would be about right. If you have good air movement you can keep the sphagnum quite wet (which will compensate for lack of humidity) That's one of the benefits of the baskets that I use - the sphag can be sopping wet but as it dries it pulls air into the root zone. Terracotta pots with sphag will also give you humidity, air and cooling in the root zone. They are very light feeders.
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08-08-2022, 01:53 AM
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I suggest using reverse osmosis or distilled water instead of tap water. Most cloud forest species are very sensitive to salts in the water. Half a teaspoon per gallon of MSU is probably a lot more fertilizer than it needs, and might be of high enough concentration to cause osmotic root damage.
Is there any way it could have cooler nights than inside your house? Cool-growing plants tolerate higher than expected temperatures better if the following nights are nice and cool.
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08-08-2022, 02:36 AM
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Tap water in some places can be very good. (Like San Francisco or New York) In other places, it can range from "OK" to "liquid rocks." The need for RO depends on where on the spectrum the tap water lies between "very good" and "liquid rocks". My tap water isn't quite "liquid rocks" but not great... and my Dracs got a lot happier when I switched to RO. So it's important to know your water quality... usually available on your water company's website,
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