I'm relatively inexperienced when it comes to growing kratom plants outside of their natural habitat. I'm based in USA and purchased 4 plants with a view to growing them, taking cuttings, rooting cuttings and then giving new plants away to my friends. Along the way I've encountered several problems, to which I've best guessed the solution, with good success.
If your buying a plant on the internet, it should arrive in a box through the mail system. Plants can survive for days, even weeks without sunlight so being boxed up wont harm them. Its the lack of moisture (water) that will kill a plant quickly. Shippers of plants know this, and plants should be packed well watered with a damp piece of kitchen roll. Mine arrived with the kitchen roll holding the soil in the pot and then tapped over. In order to ensure safe travel, your plant shouldn't be able to rattle around the box, as this will result in potential loss of leaf and/or broken stems. As kratom plants have thick hearty leafs, they travel fine through the mail system and you should have no trouble receiving a healthy specimen.
The second my plants arrived, I carefully opened the box, removed them from the packaging, water them thoroughly before placed them outside for some sunshine. I was very surprised at how healthy they looked.
Kratom grows roots very quickly and like most of the trees from around the world, they have deep roots. Be prepared for your plant to out-root even the largest of pots. When it comes to re-potting, tap the sides of the pot to loosen and remove by holding the stem at the base of the plant. If the roots have filled the pot, you wont damage anything by pulling on the stem. Place some soil mix in the bottom of your new pot and then add the plant. You'll need to pack soil around the plants existing root and soil system and then water thoroughly.
If you have red and brown spots on the kratom leafs, this is a sign of too much direct sunlight. Its a type of sunburn. If your located in a hot climate you should try and position the kratom to accept partial sunlight. many grow kratom plants indoors (south facing window) and this amount of filtered sunshine is surf ice.
This is a big problem. The only person who should be eating the kratom leafs is you. If your having a bug problem, its more than likely caterpillars. In a matter of days they can shred your kratom leafs to bits, which results in less photosynthesis. Obviously you don't want to treat your plant with a pesticide or insecticide with harmful chemicals. There are products available on the market that are perfectly safe for food plants such as tomatoes etc that repel and bug from eating the leafs. Ask your local garden center for a insect/bug/caterpillar repellant for tomato plants.
Its always recommended to mimic the natural environment for best growth conditions. Regular misting provides the plant with humidity and will promote new growth, new stems, new branches and subsequently more leafs. Be careful if your misting in the mid-day sun as the little droplets of water sat on a leaf can act like a magnifying glass and burn the leaf.
If your plant gets too cold (normally at night) it will kill the leafs and new growth stems. The leafs will shrivel up and fall off, however, still let this happen naturally - don't pull of the leafs. A dying leaf is still photosynthesizing and shouldn't be removed unless it falls off. New growth stems will turn brown and die. Don't worry about this. If you stop the plant from getting cold again, normally by keeping it inside a house or greenhouse, new growth will start from beneath the last live node. This will continue to happen unless you completely neglect your plant and eventually there are no more nodes to sprout from. You can trim off the dead wood, but don't trim back to below the last live node.
Kratom being a tree is tough to clone. If a stem or branch has any hard wood or bark, it will not root. You need to take the new growth cuttings only. Slice with a very sharp (clean) knife at a slight angle. Do not scrape the stem after taking your cutting. This will prevent the roots from growing from the scraped area. The stem should be then dipped in a rooting solution and phase 2 begins. Phase 2 is the actual process of the cutting getting roots. Methods range from simply placing the cutting in a glass of water, to complex - using a state of the art airoponics system. I doubt the roots would develop before the plant died if you use the glass of water technique. I know that you can have success with airoponics as I've tried it. I've not mastered the process, but when I have, I'll post my findings.
I have a buy kratom section here. I link to some great vendors. Tell them you were recommenced by me (kratom-world) and help me to continue my research.
If you have anything to add to this section, or if you have any questions, please email me - I'll be glad to help.