How big are the bulbs?
Generally there are three different sizes of Colocasia bulbs one the market (from smallest to biggest): 5-7 inch = 12-17 cm, 7-9 inch = 17-23 cm and 9-11 inch = 23-28 cm. The bulbs you can purchase in our shop are size 5-7 inch = 12-17 cm in diameter (the size may differ per bulb because it is a natural product).
What is the main difference in bulb sizes?
With Colocasia it’s mainly ‘the bigger the bulb the bigger the plant’. Larger bulbs will grow out plants that are taller and with much bigger leaves. In our climate we usually keep Colocasia indoors and as they need quite some space to grow (and can grow out as huge plants and not everyone might have so much space) we figured in this case a bit of a smaller bulb is the way to go.
What is the best way to pot the bulb(s)?
A few things are important before your start. Determine what is the top and bottom side of the bulb, make sure you have the right pot size and potting medium ready and determine where you’ll place the bulb(s).
⁃Determine what the top and bottom side of the bulb is.
If you look at a Colocasia bulb you’ll notice that one side it is a bit pointy. This is the top of the bulb and should be planted with that side upwards. If you doubt about the top and bottom it’s advisable to plant the bulb sideways. In any way the bulb shouldn’t have a problem growing out, it might just take a bit longer.
⁃Pot size and potting medium for your Caladium bulb
Colocasia can grow fast and large and as the bulbs are already quite big you should use a large pot. It’s recommended to use a pot that is twice as wide as the bulb. This way it should have plenty of space to root and grow. Colocasia do need moist soil and a lot of nutrients to grow. Therefor it is advisable to use a rich soil which has some good water retention and can facilitate some good drainage to avoid rot.
⁃Determine the best place in your urban jungle to grow out the bulb(s).
Remember Colocasia are tropical plants and love plenty of light and water. Therefor it’s important to place the bulb in a warm spot with enough light. A south facing window or even a little greenhouse is perfect.
How to pot the bulb?
Potting your bulb is very easy and can be done in a few minutes.
1.Fill up your pot with soil.
2.Create a hole in the middle of the pot. The hole should be between 10 and 15 cm deep, or at least as deep as its length.
3.Then place the bulb in the hole (right side up).
4.Cover the bulb with soil until the pot is full.
5.Give the bulb a good amount of water. At least until you see some water is leaking from the drainage hols in the bottom of the pot.
6.Place your potted bulb in a spot with enough warmth and light. At the stage of germination you can put it in a south facing window or even in a little greenhouse.
From now on patience is your best friend! Just wait until the first growth points appear. Do keep an eye out on the bulb(s) and water when the soil is drying out. The soil should always remain slightly damp. You can add some fertilizer to your water as Colocasia are heavy feeders.
When do I pot the bulb(s)?
Colocasia are tropical plants and appreciate warmth. Creating a warm environment is key in letting your bulb(s) sprout. If you put your bulb(s) in a greenhouse you can start potting up your bulb(s) in early spring (March/April). Otherwise it might be wise to wait a bit longer until the temperatures are getting higher (late April/May).
Keep in mind that when the temperature is too low the bulb will go back into dormancy and will only start to sprout when temperatures are increasing.
The best temperature for a Colocasia is between 17 and 25 degrees.
How long does it take for the bulb to grow out?
After potting up your bulb(s) you just have to be very patience. Depending on the environment the bulb is in it can take 4 to10 weeks before the bulb is starting to sprout. The speed of the germination will also depend on the variety. Some will just grow quicker than others. Once the first shoots appear the growth should go much faster. This is such an exciting process to watch!
Will a bulb always grow out into a full plant?
Growing Caladium bulbs is fairly easy and the bubs have a high germination rate. How ever there is always an error margin to be taken into account. In general 95% of the bulbs don’t have any problem to sprout and grow out to beautiful plants.
What to do when the bulb is growing out into a more established plant?
Once the growth points are getting larger and the first leaves are unfurling it can be a good time to give the plant a new place in your urban jungle. This will depend on the weather mostly.
When it gets warmer and sunlight is getting more intense. Be careful the sunlight doesn’t burn those beautiful big leaves. You can leave the Colocasia in a sunny spot, as long as the plant does get some shade during the hottest hours of the days. During Summer it’s also advisable to regularly check the soil of your plant. On hot days it might be needed to water your Colocasia multiple times a week. The soil should always be kept a bit moist, don’t let it dry out too much.
Does the plant go dormant?
Yes, a Colocasia can go dormant this is its normal life cycle. Especially in areas where there are obvious season changes (like Europe and parts of North America). In tropical climates a Colocasia possibly can survive the winter.
Due to the changing seasons a Colocasia will require less water from beginning of Fall. Therefor it’s important to water you plant less frequently and less water by each turn. When the leaves start to droop you can stop water the plant completely. You can wait for all leaves to die off or you can cut off any left over leaves. Get the bulb out of the soil and whip of any remaining soil. Wrap the bulb in some paper (like news paper or a brown paper bag) and store it in a dark, dry and cool area. Then in Spring you can re-pot the bulb and grow it out into a plant again!
When exactly a Colocasia goes dormant will mainly depend on the wether conditions in your country or area. In the northern parts of Europe it will get colder sooner than in southern parts of Europe for example. Thereby you might experience some late hot Summer weather in the Fall (like we sometimes have there in The Netherlands) which can expand the life your plant. Keep an eye out on your plant and you should be able to see the plants condition change.