Q. We have a gorgeous, shiny dark green star jasmine, over 25 years old. About 5 years ago, it stopped blooming and nothing we've done has helped. Please help.
A. When that happens to older plants of mine I usually cut it back pretty hard and try to get it to regrow again, getting rid of some of the older wood.
|Star Jasmine no longer flowering|
Sometimes by cutting up plant back it restores some juvenility and it responds by growing more vigorously and flowering. I would also give it a good shot of fertilizer if you haven't already and soak the roots with a hose a few times, a few days apart.
It is late in the year to be pushing new growth so you could try this in early spring instead of now. However, star Jasmine is pretty hardy in our area so fertilizing it now should not affect its cold hardiness. It will respond with a flush of new growth next spring without any applied fertilizer.
This is a technique of applying a fertilizer late in the fall to get a spring response is called late fall fertilization. Fertilizer is applied in November before the leaves drop. Nutrients are stored in plants if they are not used up. If you combine late fall fertilization and cutting it back, cut it back first and then fertilize, not the reverse. Otherwise you would be cutting off parts of the plant that has stored nutrients. Let me know if this works for you.