[Groundhog]

If you do want slower growing though, the darker in color the leaves the slower growing in general (the darker the leaves, the less photosynthesis that generally takes place, and the less photosynthesis, the less it is able to grow). I know Joshs just posted some more for sale, otherwise if you look on eBay there is always a seller with a pretty good selection, just generally smaller plants that have been tissue cultured.

Time out: Why are we equating photosynthetic efficiency to growth rate? Doesn't this only make sense at the same light intensity? Place a Pothos in higher light, you will get less green and faster growth. Same with Croton or Cordyline or Cryptanthus or Neoregelia.

I thought the deal was that plants become redder in higher light precisely because these leaves do not need as much chlorophyll, and the redder leaf better tolerates brighter (hotter) sun. Incidentally, this may be the reason why some plants have discolor leaves, to survive sudden sun exposure (See R. Kiew Begonias of Peninsular Malaysia)

Of course, light is not the only factor that affects grwth rate.

2) Both Anoectochilus roxburgii and Macodes petola are shorter than Ludisia discolor.