I had 2 of these sprout sometime in july last year. THey were in semi shade, and the soil kept drying. They didnt grow after the initial first leaf at all. I brought them inside, still in the flat. I put them in a south window in november.

In the middle of January, I decided to set up some lights for my seedfest this year. This was 7 months after germination, and they only had one leaf. They were put under lights for about 12 hours a day. The flat was prone to drying out.so by the end of January, I decided to put these in a baggie. Within the following few weeks, they put out 2 leaves a each. Growth has gone faster in dappled light from my bamboo seedlings. This seems to be backed up by RPS data sheet, which states the following:

" Native to northeastern Mexico, it grows up to 3500 m (11500 ft.) basically as an understorey plant in pine and oak forests, where the summers are cool and winters hostile. Snow, ice and subzero temperatures are the norm for these high hillsides and this Agave could reasonably be expected to survive -15°C (5°F) even in damp conditions. This is not a desert plant! "

http://rarepalmseeds.com/pix/AgaMon.shtml