Hi, I have been experiencing yellowing lower (older, but not exactly old) leaves in some neps for a long time already. It has been quite frustrating as some of these leaves are clearly dying due to factors other than age.
I am considering supplementing a little MgSO4 in the fert, as it seems a deficiency in this may result in some of the symptoms I'm seeing. I have also heard from orchid growers that it is a good addition regardless of deficiency or no. Has any one been doing this for their neps and can share experience on it? And would an addition of this on top of the usual seaweed extract ferts be overdoing it?
I have also heard some disturbing information that allowing the sprinkler to go off in the middle of a hot dry day can cause more harm than good. According to this, water sprayed onto the leaves quickly causes humidity to rise. the temporary relieve from the drying winds and scorching sun causes stomata to open up, but when this water evaporates (and it does so quickly), the stomata remain open and the plant loses more water than it would without the spray. My sprinklers go off 3 times during the hotter part of the day, so I have many reasons to get worried about this. But can anyone verify (optimally with personal experience) ?
Post by stevestewart on Oct 13, 2008 2:15:42 GMT -10
I have had Nepenthes show classic deficiencies that would require nutrient application in many other foliage plants, but not in Nepenthes. I have noticed that some species in this family of plants are unable to utilize nutrients in unfavorable conditions. I believe this is why some growers believe low nutrient levels are responsible for flowering in their plants.
I'm not saying not to fertilize your plants, but be careful, and try to modify growing conditions as a part of your adjustment in culture. Some Nepenthes species will show early leaf problems because of light levels, some because of temperature extremes or both.
I just this week moved many of my N. ampullaria seedlings to a more shaded area because their leaves were yellowing, getting shorter and spotted. The one plant I moved two weeks ago, has improved greatly, and looks as if I had fertilized it, when I have not.
Post by rainforest on Oct 13, 2008 9:00:21 GMT -10
Lamwn, I would be more interested in seeing what sort of chlorosis is occurring. Inter-veinal vs. veinal or whole leaf yellowing. From where this yellowing starts and whether there is browning also associated with this. Sometimes there is a patch of green surrounded by yellow/brown tissues and other variations. A picture is worth a thousand words.
I have two plants next to each other that recently became "variegated" (N. x bauensis and N. viking). The leaves are off-white and yellow green. Could this be viral, fungus, or mineral deficiency? I'll post pics tomorrow. TIA!
Hi, thanks for the responses, and please forgive the slow reply. Here are the pics:
I'm not sure if it looks like a nutrient deficiency in the first place, as I'm not very experienced. but to me, it seems as though the plant is withdrawing energy from its older leaves in order to put out new leaves. Some of the plants that have shown these symptoms for a long time attain a 'palm tree' type growth,
About how I decided on Mg... I cant seem to pin point a given cultural factor which could cause some of what I'm observing, although there are a lot which I may not have considered.... HOwever, should it be a nutrient deficiency, I remember reading somewhere that micro elements are all immobile, hence deficiency is observed first in young rather than old leaves, so I ruled those out. When considering the macro elements, Mg seemed to fit best...is Ca possible?
Not ignoring what stevestewart said, I've examined things like light, air circulation, and several other factors but cant seem to make a direct connection between this and a cultural factors still...
Anyway, I posted something like this some time back, and the closest I got to a hit was overly acidic media, a contribution from Rainforest (thanks!). I've tried adding lime and other basic substances to change that, and have noticed some other positive effects here and there, but the problem with the leaves still lingers.
Any help would be greatly appreciated. thanks! Lam
Post by rainforest on Oct 16, 2008 8:13:47 GMT -10
Very good assimilation my first thought is a breakdown in media composition especially at the root ends. This breakdown will cause some root rots responsible for this kind of damage. Since I have added coral chips to my media (especially drain exits) I do not encounter such problems any more.
I make a strong statement regarding basic media incorporated in a general organic media.