Ok, my Ludwigia is the first plant I've owned thats reached the waters surface (proud moment ), but how do I trim it back? I assume halfway between a set of leaves, vertically, but I'd like to check. I'd like the Ludwigia to bush out, so is it better to trim more often, before it reaches the waters surface?

Also, can I replant the trimming to try and cultivate a new plant, and if so whats the best way to go about it?

Thanks again. I know I'm asking a lot, but I'm still learning.

Uhhh...I've heard of ludwigia repens/natans and Alternanthera rosaefolia, but not ludwigia rosaefolia

Anyway, if it's ludwigia, just trim it the way you described it. The trimmings would survive replanting if their stems aren't too young to grow on their own (Young = soft, floppy stems). If it's an alternanthera, just cut below the "knobs" and replant. It's kinda hard to describe it, but there's a series of knobs on an otherwise smooth stem. I've found new roots grow out of them.

Thanks for the reply!

I cant find any info on the plant either, but it's the name given to me my Maidenhead Aquatics. I think Rosaefolia means 'rosy leaves' which indeed it does have. I'll have a go mid-next week, as I'm tank re-arranging this weekend Woo-hoo!