I live in new york rite on lake ontario, ive had colocasias for years, my pride and joy.. and theres alot of controversy about them, how to grow them, over winter them and so on and through trial and errror this is wut ive learned if it can help any one..1st they love food and not the liquid kind..but horse cow or goat manure..(must be seasoned a year or 2) soil is the most important aspect in growing these badboys...i make my own dirt for all my plants,,try merical grow potting soil (1/3) with manure (1/3) and ne kind of regular dirt or sand (1/3),,and i sift it useing a regular strainer to get the finest loosest n fluffiest dirt n i mix it all together and my plants thrive,, always remember to water weekly depending on climate ect,,the bigger the plant the more food and water they need,,(use rain water or distilled..tap water has to many chemicals and clorine which will damage ne plant over time) i also never put mine in the ground they are all in pots,, they make an awsome house plant,, they go outside in the summer and come indoors in the winter they never go dormant on me..i do not c the point in over wintering them if they r still healthy, and growing fine unless they r in the ground and u dont wanna risk loseing them from winter or u dnt hve the room to bring them indoors.. they will let u no if there going dorment if thats the case i wouldnt cut them back let them die off on threre own as long as they hve foliage they r absorbing nutrients to store for next years growth.. ive also learned (and this may sound nuts) they r like children with thier own personal prefrenses and personalities,,yes i said it..a plant adjusting to a new home..? sometimes and certain plants i no for a fact drecenea is 1..but when u hve a healthy colocasia..a new home dosent matter to them..idk this is wut ive learned over tha past 15yrs of having these n i can take it to the bank..i could rite all day about these plants so i hope this can help ne 1 thats looking for advise.. it is a science and with enough research (weighing out the opinions and answers) ull figure it out be paitient and proactive.. and good luck

Well, that's why I said when I posted that that "your mileage may vary",lol. Its hard to tell people exactly what to expect and how their plants "should" behave when your comditions are quite a bit different from theirs. I can only tell you my experience HERE where I live. Perhaps you can draw from it. If it helps you that's great, if not, you may have to rely on the experience of someone in your same zone. Alocasia, Colocasia and Xanthosoma grown outdoors in the ground, or in water or a bog situation here are very variable in their reaction to cooler temps. We are in zone 9, but barely. On average, we get a few "frosts" (defined by ME at MY HOUSE as nights where the temps are between 27-32F) and a few "freezes" defined again by ME as between 20-27F. Xanthosoma and colocasia grown in water (ponds, natural bogs) sometimes NEVER go dormant. They can stay up all winter, even through freezes to 25-32F here. Sometimes it takes temps in the 20-25F range to knock mine back. However, Xanthosoma and colocasia grown as purely terrestrial plants in the ground will begin to respond FIRST to the decrease in water that accompanies the onset of fall here (we typically have very dry winters)by producing less leaves and smaller leaves. They are also responding to the shorter days. Once the temps fall into the upper 40's/low 50's at night and stay there, some of the terrestrial colocasia will disappear. Some won't. I find it depends on where they are planted. Those planted under tree canopy get less winter sun and disappear. Those in full sun stay longer. Alocasias are variable in their response to cooler temps as well. I have several species planted in my yard and they all behave a little differently. The trunking forms of alocasia (culcullata, calidora, odora, portodora, sinuatis, etc) will maintain their foliage usually until it freezes off in the 20-32 range. The trunks, however, stay intact, and generally no action is needed to protect them in our winters. The non-trunking forms (macrorhizza, frydek, black stem, plumbea etc) act more like colocasias. They begin to respond to less water and less light well before they begin to respond to cold. By the time the temps are in the 40's and 50's, they have usually disappeared for the season. They are dormant UNDER the ground, and we either just ignore them or maybe mulch over them til spring, when they pop right out again. If I was going to try to bring a container of alocasia inside for winter, I would bring it in NOW and put it in front of my sunniest window, and water it once a week. If the conditions were to its liking, it would stay up and growing as a houseplant. If not, the leaves would die back, then I would put it in, maybe, the laundry room? til Spring.

It is perfectly normal for colocasia leaves to fold at night. What is "root stabilizer"? If you are fertilizing (and don't get carried away with that), then the plant needs no other supplements other than adequate water. More light will help the leaves color up properly.

Don't put table salt in your soil. Plants use osmosis to pull the get water/nutrients from the soil. Plant roots generally take up moisture by a type of osmosis through membranes in root cells. Osmosis is a natural process where water, passing through a semi-permeable membrane, moves from a solution of low levels of dissolved salts to one with a higher salt level. This process allows water to move from a solution of relatively low concentration (the soil moisture) into a solution of relatively high concentration (in the plant root cells) in an attempt to establish equilibrium in the two solutions. This continues until the plant cells become full, or turgid. IF you place salt in the soil then the soil has the higher concentration. If the soil moisture is moderately saline, the plant has to work harder to absorb water from the soil. With lack of water, the plant soon begins to wilt, and growth is slowed, with reduced yields. In highly saline moisture concentraions, the process of osmosis can become reversed. Where the solution outside the plant roots is higher in salt concentration than that of the root cells, water will move from the roots into the surrounding solution. The plant loses moisture, and so suffers stress. This is why symptoms of high salt damage are similar to those from high moisture stress: leaf tip dieback margins yellowing, scorched and turning brown or black, followed by leaf fall of dead leaves Please bear in mind, I'm not speaking about Epson's salt which is magnesium sulfate not table salt (sodium chloride).