I must say in comparison to all the hype and trend taking place concerning Colocasia - this particular variety which is known as the "Black Magic" variety would be the most easiest and can be best described as the beginner level plant before venturing into the more advance and expensive types of Colocasia.
However, don't under-estimate this plant as it is not extremely hardy and does require some Care & Cultivation and some hands on to really figure out how it actually grows and thrive in the garden space.
I had found that the foliage coloration do change colors and producing veins like features - something to say that it spans from the matt like black to grey shades and the other extreme of total green with some black veins.
This often happens due to lack of sunlight and to some degree lack of nutrients to support the plant to change in black pigmentation - hence the plant reverts to green to make it's own food.
However, in comparison to other counterparts - black magic Colocasia is very much a hardy type and may able to sustain and live longer with many conditions thrown at it.
The best ideal condition would be in a situation where it is planted like bog / swamp like conditions as it very much behaves like an aquatic plant - and the factor is when it is actually planted in a wet feet - this helps the plant to regulate water intake well as it indeed a very thirsty plant.
Lack of water at the root ball can cause leaf burns at the edges and may also cause the leaf stem to wither during hot and dry climate. Another factor which is often unseen are the invasive like behavior where these produce lots of root runners out of it's designated growing pot - often overcrowding and may appear chocking as the lack of growth space.
This is one of the factors where they tend to be sabotage itself as the root-ball raised above the planted potting media and sort of cut off from receiving necessary water intake - often there will be a need to arise where you may have to repot them, separating the heavy runners and setting back the root ball into a well balanced rich soil medium as to ensure good plant growth and set for the next cycle of re-generation.
I might not suggest that Colocasia Black Magic goes dormant - however I noticed dormancy does take place when the plant is not receiving adequate water or nutrients to begin with.
Also I had noticed many new varieties under the Colocasia Black Magic wing have been introduced which may be very similar and slight variant difference - to name a few: Black Runner, Black Magic variegated, Colocasia Madeira and a few others.
(Pic Above: Due to lack of Sunlight - the Foliage Coloration turned bronze tones with green veining appearing in a unique structure - the leaf however are water proof)
First thing First, You can get away with everything else but not without the Water Factor.
They need to placed inside a water-body most likely inside a water container. The leaves will have burned sides if lacking water.
If at all these were planted in non stagnant soil medium due ensure to put a pot saucer under the pot as to keep the medium almost soaking wet. However, this can also be slightly tricky if the plant develops root rot - hence do watch to get the right balance where no root rot takes place - the right balance soil mix actually helps where the medium doesn't contain rotting agents.
After many trial and errors - I had found that the best mix where it is very much putting them as layers before planting the root ball - usually I will place a layer of cotton fiber, fill the bottom with a good amount of compost mix with chicken manure, next with balance mix soil and placing the root-ball and fill it up - surrounding the root ball with river sand to ensure no root ball rot takes place.
The Potting Medium and Daily Watering Goes Hand in Hand.
This way, I really don't have to worry about root rot and water stagnation which may breed mosquitoes - especially in my region where Aedes mosquitoes can easily breed in such conditions.
This is very much the other important factor when it comes to Colocasias, these are Sun lovers, lack of it may not be good for them - usually they may produce few sprouts leaf foliage - often appearing sickly and green, the stem always appear too fragile and long - looking for strong light source hence it may fall and break under it's own weight.
Often times, when these get stressed, you will end up finding - mealybugs and spidermites infestation on the leaves usually a very bad and heavy infestation which may force you either to trim off the leaves or get rid of the plant altogether to cut the risk of infection to other healthy plants.
The main factor is always the lack of direct sunlight and open rain that creates the hardy factor where non of these pest may able to sit on the foliage due to these elements - however, with consistent application of pesticide - you may able to control and deter these infestation.
Don't take this factor lightly, once these pest made into your collection - it may take many weeks with strong regiment of constant application of pesticides to totally eliminate them from your garden. The most stubborn ones are usually the spidermites followed by mealybugs farmed by ants. Another stubborn pest would be scale insects and alphids.
Using the right pesticide and consistent application is the right key to eradicate these pest as the damage on the foliage can be very evident and heartbreaking.
Another pest which I'm intrigued to find are caterpillars from a moth species - seemed to be attracted to these foliage. Often find them munching away on rare and expensive Colocasia - do take note on that as the damage can be severe when your 3 leaf plant are gone eaten overnight.
FEEDING / FERTILIZER:
This is another key factor: Normally I use half strength diluted foliar fertilizer sprayed on the foliage on weekly basis. This helps to stablize the existing foliage and add new shoots - new leaf foliage growth. I found that Colocasia Black Magic seemed to grow fast and steady in comparison to other varieties.
(Pic Above: Due to lack of watering the burned marked appears surrounding the leaf edges)
Propagation are usually done using rooted runners or root ball division when they form more than few colony like plants from the singular root ball area. This may require full uprooting and repot the whole plant - separating the plant-lets carefully as no minimize root ball damage.
Do refrain from putting a plant-let from the pot as you may accidentally snap breaking the plant into half without the root structure attached to the stem and leaf structure - it is always best to repot and you can ensure better success and stability of the plant when separating the babies from the mother plant.
I have seen this one looks larger and bigger when planted in bigger and deeper planter box, hence it does makes a difference when repot into bigger pots with more rich soil medium and good watering - they can grow much larger and in good balanced color.
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