As much as I like to remind everyone of how easy it is to perpetuate many of their perennials for ever, and to share with their friends, neighbors, children, grandchildren, great grandchildren and so on, there are just some perennials that are not meant to last. I do not mean that they can not last; only that they are not as easy to sustain as others are. For most of these not so easy to sustain perennials, the original plants actually die completely, so will only be sustainable if replacement copies are propagated by cuttings or layers before the demise.

             Many of the very easy to grow daisies and daisy relatives are actually not as self sustaining as they should be. Clumping gazanias can actually rot out in the middle after a few years. Before this happens, it is rather easy to propagate replacement plants from division of mature clumps, or to take small cuttings, even though clumping gazanias do not often need to be pruned. Alternatively, side shoots can be layered (pressed into the soil to form roots) right next to parent clumps. Only a few replacements are necessary, but without them, clumping gazanias eventually die out.  

            Even trailing gazanias can eventually die out. Because they sometimes need to be pruned around the edges, there is a regular supply of material to make cuttings to patch bald spots. To get bigger cuttings, I actually like to delay edging until the plants look shabbier than they should around the edges; but my neighbors do not mind. (At least they do not tell me if they mind.)

            Shrubby marguerite daisies (not blue marguerites) and euryops likewise need to be replaced every few years. If there is enough space, outer stems that lay on the ground can be layered. It is best to bury each layered stem in a small hole, and then hold it down with a stone or brick. The layered plants may not be so symmetrical when the parent plants die out, but should fill out nicely. The fourteen euryops in the long park-strip in front of my home did not have enough space for layering, so died a slow, miserable and unsightly death until I finally removed them. If I had planned better, I would have taken cuttings to replace them.

            It is a surprise when pink breath of Heaven (Coleonema or Diosma pulchrum) or coyote brush dies suddenly, because they are really woody shrubs. (Although coyote brush is actually of the family Compositae like gazanias and daisies, etc.) Various ceanothus live longer, but not much longer. These woody shrubs are not so easy to layer, and quite difficult to root from cuttings, so often get replaced with new plants from the nursery, or different plants.