The Dieffenbachia Amoena plant Is a rather common large house plant. They have beautiful patterned leaves and thick stems. They can also hit your celing. Over the years I have developed a method similar to "Air layering" to root the stems and keep the top of the plant. But instead of moss and cling wrap I use 2 Liter pop bottles and potting soil. I call it "Pillaring" after the Minecraft technique of stacking dirt blocks to get away from monsters. Please join me as I root my crazy big house plant and re pot it.
This is Gronk. He has been with me for literally decades. He has been my Christmas tree when I was broke, He almost got me strip searched at the airport (Never bring a root ball in your carry on luggage), He is mildly toxic, fast growing and spoiled. I am now at the point where if I want to buy him a new pot I have someone bring it to the cash register with a forklift. I have more stories about Gronk than any sane person should have about a house plant. Gronk is my friend. Now watch me hack him into pieces....
Step 1: Pillaring Up
Cut a hole just big enough for the stem in the bottom of a pop bottle. Cut the top off the bottle and split the bottle up the side. Now put the bottle around the stem. Tape the side of the bottle shut fill it with dirt and wait. Keep the dirt moist and in a few weeks the roots will be visible all around the bottle. On larger plants you can use a few bottles. If you get everything lined up right when you water the top one the water goes down into the second and third. On the stem there are little "eyes" like a potato. These points are where roots and leaves usually pop out.
Step 2: Rooting
After a couple weeks you will begin to see roots thru the plastic...then more roots. When you see roots everywhere in about a month it is time to stop watering for a couple days and prepare the birthing chamber.
Step 3: Happy Birthday! Congrats! It's a Hermaphrodite Clone!
If you have no dedicated birthing chamber a kitchen will do. Spread out a tarp and pick out a large sharp clean knife. Cut quick and cut deep, remember this is your friend. No need to drag this out. Peel off the bottles and save them for the next rooting. Each leafy top gets a bottle of roots and a pot as does each rooted chunk of stem. Make sure you have enough soil and pots before you start. Bury the stems of the tops deep so the stem supports the mass of the plant. By having a large root ball under the plant's top you get the maximum growth out of the plant. Shortening the plant is not a setback.
The babies will form a leaf node and the first leaf will come out. They take their sweet time about it (weeks or months depending on conditions) Sometimes they pop up out of the dirt in random places and nowhere near the stem. Never assume a baby is dead. I have never had one fail. You can easily sell these plants for $25 when they have a few leaves especially if you show them the parent. It isn't much but enough to cover the cost of pots and soil at least. You can totally bury your babies but I prefer having a bit of non rooted stalk poking up. These are rather large stalk sections. I have made them half this size and still had 100% success. I just don't have room for 12 plants at the moment.
Don't they look happy now?
Step 6: Maximum Growth
You might be wondering about how this plant got so big. There are many varieties of Dieffenbachia and this happens to be one of the largest. It has the genetics to be a monster plant but it needs care too. Every couple months it gets some plant spikes. Pretty much one spike for every severed human head that can fit in the pot. This happens to be a four head pot. I also bury eggshells (breakfast, unwashed) for calcium at least once a month in the pot and if you look very close all those tiny headstones are various flies I have killed in the house, I don't know if the flies help but the tiny headstones make me laugh. Water often but if the plant starts to cry back off on the water a bit. They will literally drip water from the tips of their leaves if you give them too much. They also like water in the little hollows at the base of the leaves and in the top of the plant. Never yank a leaf off. It is natural for them to lose lower leaves as they get taller. If you pull the leaf off it will scar the trunk and retard stem growth (see pic above). You can cut the old dead leaf off close to the trunk but let the leftover bit dry and fall off on it's own. Occasionally they will make strange primitive peeled banana like flowers but it will never self fertilize. The male and female parts are in the same flower but mature at different times. But as far as I can tell you can clone this plant thru cuttings indefinitely... or at the very least for 25 years or more.
Step 7: Where Gronk Came From.
Gronk is from The Maples in Winnipeg Manitoba. I was just a kid and driving a really crappy car. An old Mazda. It was spring and I was driving to my girlfriend's place. As I was driving I saw this old woman sitting outside reading on her front step with plants all along her front walk up to the sidewalk. The plants were all in cheap throw away garden pots and cut up milk cartons. There was no sign or anything but I assumed it was a plant sale. I stopped and walked up. I asked her how much the cute little plants were.... no response. I looked at the front of her book. So not English. I took out my wallet and pointed at a cute little plant with two leaves no bigger than my hand. Then I showed her the two $5 bills I had. She looked at me, then the plant... then my crappy car. She took $5 and gave me the plant. I thanked her, went back to my car and buckled him in. I showed it to my Mom and she said "That's a puppy with BIG feet!" I asked her what it was. She said it's a "Gronk" And that is what I have called him ever since. Little did I know he would grow to such a size or become such an oddly important part of my family. I know he is toxic but two kids and many pets later he hasn't killed anyone. Not even a rash. I hope this encourages you to add a large plant to your family. They are worth the effort and an amazing addition to any home.