Hi:
My pleasure. We grow a very extensive collection of South African bulbous plants.
If your plants set seed, the capsules of longifolia are ovoid, up to 8 mm. at the widest diameter. In lewisiae, capsules are more cylindrical, up to 3 mm. at the widest diameter. Otherwise the plants are very similar.
M. (H.) longifolia sets so much seed here and we have distributed so much of it around that it is probable that yours is longifolia. It is a superb plant when grown in the ground, flowering for over two months, non stop.
Best regards
