Lemongrass is something I have grown before and is extremely easy. Just stick a couple of stalks in a glass with a layer of water. Change the water daily (or when you remember) and just watch the roots sprout. When you are happy with the root growth just stick it in a pot with some good soil and put in a nice sheltered spot outside (I am anticipating these to root really well within three weeks and after that it should be warm enough outside).
Pandan on the other hand I haven't grown. The Internet is not very forthcoming with how to grow these cuttings so I am trying two different methods. One plant I stuck in one of the seedling modules and the other in a layer of water (like the lemongrass). Let's hope at least one of them roots. Again if rooted they will be planted in good soil and put in a warm sheltered position in the garden.
I am going to need a piece of ginger tonight so I am not going to be planting the whole rhizome. As you can see there are some good fat growhtpoints at the top. First I will slice of the ginger I need keeping the best growthpoints conserved.
Normally you would plant ginger a bit like you plant bearded iris, letting it lay on it's side exposing the top of the rhizome. However with this piece I am going to plant it with the growthpoints pointing upwards leaving the very tip of them exposed, this way I can get a clear view at how it is growing.
This way I'll have some lovely fragrant leaves in the garden. I must tell you I probably will not be concerned with keeping these through next winter (maybe the pandan, I am not sure yet). I think it likely I will just harvest the ginger, and dry the lemongrass (pandan leaves freeze really well). So no room will be spend keeping them alive and for a couple of euros you can just restart this process next spring!