dividing ornamental alliums
I have two remaining 'Gladiator' alliums in my herb garden...full sun, well-drained sandy soil top-dressed with compost once or twice a year. I started with three, in a triangular arrangement which complemented the other plantings beautifully. Two look kind of like they`re missing their third. So I now have two questions: Can and should I divide the remaining two, to fill the empty spot, and what does anyone think of the conditions I`ve described? Would anything have caused the demise of the original third? Okay, so it`s three questions: what is the best time of year to divide alliums?
I much appreciate any info.