Daylilies have a way of quietly taking over a flower bed. A plant that once produced an attractive mound of foliage can eventually become a dense clump with fewer flowers in the center, signaling that it may be time for some attention. Dividing an established plant rejuvenates the planting while turning one daylily into several plants you can use elsewhere without spending another dollar at the garden center. Fall can be a good time for dividing daylilies, but timing matters because newly transplanted roots need an opportunity to become established before serious cold arrives. If your clumps have become crowded, here’s how to divide them without unnecessarily damaging the plants you’ve spent years growing.