There is so much positively certain, yet completely incorrect information about pruning Gardenias. So instead of debating all of the different theories and expert opinions this is simply an article about actual experience: what we do, and have done for over a decade, with excellent results.
The Old Wood – New Wood Debate
As with Hydrangeas, Azaleas and many other plants, there is always debate over whether Gardenias flower on old wood, new wood or both. Since this is our business every day of the year, we are forced to experiment and test these rules of the garden all the time. Frequently, our pruning schedules are driven by the addition of a new garage or the replacement of a sewer line. We are forced to prune or transplant at the most inopportune times. We have seen the actual results of pruning Azaleas in February, Hydrangea Macrophylla in April and Gardenias all year long.
Keep it all in Perspective
First of all, when it comes to the “old wood-new wood” debate, try to keep it in perspective: we’re talking about one season’s flowers. That’s it. We aren’t talking about the life or death of a family pet – just one season’s flowers.
To that point, if we are doing major structural pruning (always by hand, of course) we always do it in mid- to late-winter. Even if we are pruning Azaleas, Hydrangea Macrophylla, Bridal Wreath Spirea or any other plants that flower on new wood. Yes, we will sacrifice the current year’s flowers, but with the extreme fluctuations in our weather we believe it’s the safest decision. In recent years, Atlanta has experienced March temperatures near 90 degrees and summer temperatures as high as 106 – not exactly ideal pruning weather.
Pruning Gardenias – Old Wood, New Wood
Over a decade of experience pruning Gardenias has shown that Gardenias definitely flower on old wood . . . and . . . they also flower on relatively new wood. They aren’t likely to flower on new growth that’s 2-3 weeks old. However, weather permitting, they are likely to flower on new growth that’s 8-10 weeks.
Basically, Gardenias respond well to proper pruning, almost regardless of the timing. Pruning throughout the year will make for a very productive, healthy plant. For maintenance pruning, we focus on three times of the year, if needed:
When pruning Gardenias, the month or two immediately after the Gardenia flowers is most important. This is when we take them down to about 70% of their target size (if size is an issue). This allows the plant to grow to the desired size and for new growth to mature without being constantly assaulted with pruners. We try to prune with future growth in mind because constantly whacking on a plant to keep it below a window just isn’t healthy. We also reduce the interior density. Flies have become a real problem for Gardenias in Atlanta. Opening the plant up allows more light and airflow, which makes a less attractive environment for White Flies. This is the most effective time for maintenance pruning. (See Benefits of Proper Pruning)
When pruning Gardenias down hard, by one-half or more, late winter is the safest time. Yes, you will absolutely, positively impact flower production. Depending on how deep you cut, and what percentage of the plant you prune, you may still have flowers . . . but you may not. We call this “renovation pruning” and the only time we recommend doing it is when the weather is cold, but warm temperatures are on the way. Gardenias respond well to deep, winter pruning – bite the bullet and sacrifice one season’s flowers for the good of the plant.
If you do your summer pruning properly, and you planned for how much the plant will grow in the coming months, pruning Gardenias in the fall should not be necessary. If you have to prune in the fall, tread lightly. You can take the plant down 5-10% to get it away from the side walk or to bring it below a window, but nothing more extreme than that. If possible, skip it and wait for late winter or summer.
Monrovia is one of the most well-known growers in America. Click here to see the different varieties of Gardenias.
My Personal Gardener is a full-service landscape company in the Buckhead area of Atlanta. We are avid hand-pruners and shun the use of power shears. If you are interested in learning more about the work we do please contact us for a free evaluation and proposal.