I recently cooked a Thai dinner with ingredients from my greenhouse, including kaffir lime leaves, galangal, lemongrass, Thai basil, and Thai hot peppers. Here are tips on growing each.
Kaffir lime is a small tree with serrated leaves that are chopped or sliced into tiny slivers. To harvest these leaves for Asian meals, buy a small Kaffir lime plant, pot it up, and wait for it to grow. It will also produce harvestable, knobbly-looking fruit about the size of a green tangerine in about two years.
Galangal is a root crop that can be grown like ginger in a wide, shallow pot to allow the roots to spread. A pot 10” wide x 6” deep will do nicely. You can buy galangal in most Asian markets. Select a piece with a cut-off stalk and rinse it in fresh water in case it has been treated to prevent sprouting. Plant the piece in regular potting soil, and soon the stalk will start developing. The leaves are quite large, up to three feet tall, and eventually grow orchid-like flowers. Like ginger, galangal requires a long growing season and does best in a warm greenhouse with a temperature around 70oF. To harvest the root, simply dig up the plant, wash it off, and voila! You have fresh galangal.
Lemongrass is another delicious herb you can easily grow in a greenhouse either from seeds or from a small piece of lemongrass plant. If starting with a piece of plant, be sure the piece has intact roots. Then set it in a pot containing slightly sandy potting soil (40% sand and 60% potting soil) and the plant will quickly begin to spread. A single small piece will become a sizable clump in just one season. You can harvest what you need and use a few pieces (again with roots intact) to grow more. In a couple seasons, the single piece I started with has grown into several clumps that provide more lemongrass than I usually need. You can also freeze the harvested plant for use any time.
Thai basil and Thai hot peppers can both be started from seeds purchased online. I start mine under grow lights in early spring so that the plants will be large enough to pot up and put in my greenhouse by early May. Thai basil can be used with kaffir lime leaves or kaffir fruit to make Thai curry paste or tom yum soup paste, both of which can be frozen for storage.
So if you do Asian cooking, consider growing your own Asian herbs and spices. They’ll be incredibly fresh, healthfully organic, and ready when you need them.