Ask Mr. Smarty Plants

Ordinarily, we make comments about the expertise of the Lady Bird Johnson Wildflower Center is in plants native to North America. We find, however, that plants referred to as "mock orange" not only are native to North America, but Asia and parts of Europe. So, we'll just single out one that appears in our Native Plant Database, and use it as an example.

We will assume that possibly your shrub is Philadelphus microphyllus (littleleaf mock orange) which is native to the Southwest from Texas to California. It blooms with white flowers in March, April and May. The problem with flowering shrubs that are not flowering, native or not, is often too little sunshine or too much lawn fertilizer. Obviously, if you have it in full sun in Austin, that is not the problem. Lawn fertilizer, which possibly is being spread a little farther than the lawn, is high in nitrogen for green leaves (or blades) of grass. A plant you wish to flower but give too much nitrogen will get lazy and fail to bloom. A plant has just one goal in life and that is to reproduce itself. To make seed, it must make flowers, but if it doesn't feel just a little bit insecure about its future, it won't expend the considerable energy to create the flowers. Another suggestion is about the way you are pruning your mock orange bushes. The best time to prune most flowering shrubs is right after flowering. Cut back the outer stems that have flowered; each cut should be made just above a strong outer facing bud or new shoot. Next year's blooms will appear from these buds.

So, you say, how can I prune it right after it blooms if it never blooms? We are now in the bloom season for your mock orange. Hopefully, unless it's bloated on nitrogen, it will make some bloom attempts so you can locate the spots to prune. If that still doesn't work, and you get no satisfactory blooming next year, we'd vote for dig it up.