Topic: I repotted my Colacasia and I think I've killed it.

[raisedbedted]

I bought 4 Colocasia's last summer which have been doing nicely all through the winter, lots of new leaves etc.  So much so that a few weeks ago I repotted two of them into normal compost.

Since then the two that have been reportted have slowly had all their leaves go limp and a white mould at the leaf base has appeared.

Is is that the repotting has prompted their annual dormancy or have I killed the poor fellas?

[woodypecks]

A nursery near Charmouth was selling some ENORMOUS colocasia corms/bulbs...I couldnt resist buying one ...I have potted it up and named it Nellie ....as in Nellie the Elephant....I just hope I ,ve planted it the righy way up .   Debbie  :)

[woodypecks]

.......but to reply to your querie... were  yours in a greenhouse or conservatory ?   I was told that they do go dormant during the winter and you,ve kept yours going ? Maybe you gave them too much water . I think I would tip them out and start again with just very slightly moist compost ,as it comes out of the bag .  Do you keep them as house plants or do you ever put them outside in the summer  ? Debbie

[raisedbedted]

I think the problem was that after I repotted them they wilted slightly so I watered some more, they wilted more and I watered more etc etc.

Following a very helpful pm I have taken them from the pot, dried the tuber and replanted.  The crown however really was quite rotten (in only 3 weeks) so I dont hold out much hope.

No the plants have never gone dormant and have been growing all through winter, they are in consrvatory and in the summer go outside on pond margins.

[Alocoloman]

Hi there

I have been growing Colocasias for over 7 years now and they are relatively simple to look after if given the right conditions. Colocasias are mostly naturally south-east Asian swamp plants - not truly aquatic plants. Therefore as the winters in their natural environment are very much drier than ours that is where the problem occurs.

Colocasias will stand lots of watering in the growing season - in fact mine grow as pond marginals feeding on the huge amounts of nitrate available courstesy of many rather large assorted fish. One thing to be aware of even in the growing season is that some species e.g. Colocasia esculenta (the standard green form) will quite happily tolerate its roots being wet, but doesn't like to be submerged i.e. the crown needs to be kept above the waterline. However Colocasia esculenta var. aquatilis (lovely red stems), as the name suggests, is truly aquatic when in growth thus is happy to be immersed in water.

For all Colocasias the overwintering is basically the same (although some become dormant at 7 degrees C and some will remain in growth down to say 1 degree C). The key thing is not how cold they get, but how wet they are. When in dormancy the corm will rot if it is left wet. Colocasias from my pond are removed before the cold weather sets in and repotted into DRY peat free compost. Then they are just left unwatered in an unheated greenhouse for the winter (except black magic, which I will come to later). As the leaf growth stops ( leaf support is dependant on watering) the leaves are removed as they wilt then if the temperature doesn't drop too low the Colocasia (as discussed above), particularly burgandy stem, will keep growing. But even then kept on the dry side and only watering from the bottom. If growth stops then the temperature has dropped too low so just leave be i.e. no water at all until at least the end of February - say the middle of March this year, when the sun has reappeared strong in the sky, the compost can be warmed by it and the dormant corms will be encouraged to regrow again. Once they start to shoot then commence watering gradually from the bottom and they will grow again happily.  Now back to black magic - this plant is particularly difficult to encourage to regrow from dormancy, so best to simply move it indoors and keep it above 7 degrees C where it will appily keep growing throughout the winter - then it can gradually be moved outside when the sun is nice and strong again.

I trust this information is helpful to you all

Happy Growing  :)

[woodypecks]

I,m beginning to think I planted the bulb upside down ,so I,m going to tip it out and see if anything is happening down below !