How to Make Your Orchids Bloom Again: Patience and Know-How

As soon as our orchid stops flowering, we start to hope again…

But the arrival of the next bloom is often slow to appear. To help you wait, I suggest examining the two fundamental principles that govern orchid flowering. A better understanding of how your plants function will allow you to optimize your growing conditions and thus improve your chances of success.

First Requirement: The Accumulation of Sufficient Reserves to Fuel Flowering.

As we explained in a previous column, orchids are generally cyclical, meaning they grow by following the natural cycle of the seasons. Generally, they begin a growing year by producing new roots, then build and deploy new leaves. Strengthened by this new, young, and efficient tissue, the orchid will be able to increase its production of carbohydrates through photosynthesis and build sugar reserves. If necessary, I invite you to reread the column on photosynthesis published earlier this year.

Only when reserves are sufficient and there is enough time left in its annual cycle can the orchid engage in the demanding flowering process. If there is a lack of time and/or reserves, it will refrain from flowering, preferring to wait for a future cycle when the chances of success are better.

In practice, if the growing conditions are not stimulating enough, your orchids will barely manage to produce roots and foliage, but they will lack time to build a flower stem and make flowers. In other words, it will take very good growing conditions to reach a sufficient level of reserves, and quickly enough to complete flowering in the current cycle!

The formation of sufficient reserves for flowering is therefore the first requirement. This can only be achieved through several months of vigorous photosynthesis and rapid growth, allowing flowering to be completed, well before the end of the annual cycle.

Second Requirement: The Triggering of Flowering by Certain Environmental Factors.

This requirement is a little more subtle and is often one that orchid enthusiasts tend to overlook.

Indeed, many orchid species wait for a specific environmental stimulus before flowering, even if their sugar reserves are abundant. Biologists who have studied the issue believe that some plants are thus trying to “synchronize themselves” and synchronize with their pollinating insect. This synchronization between plants and pollinators would greatly improve the chances of fertilization and consequently the survival of the botanical species in its habitat.

The triggering stimulus can vary greatly from species to species. Quite often, it will be:

• either a particular temperature variation (for example a drop in temperature as in the case of certain Vandas and several Cymbidiums),
• either a water modulation (for example a period of high humidity as in the case of several Bulbophyllum)
• either by a variation in the length of the day (duration of lighting as for several Cattleyas).

In many hybrids, however, there is a certain desensitization to flowering stimuli, since crossing plants with different needs will attenuate the apparent reaction of their offspring. Moreover, hybridization specialists will often favor these “desensitizing” crosses to simplify the flowering of hybrids and make it possible to flower at different times of the year.

Here Are Some Practical Suggestions for Making Your Orchids Bloom

I suggest you take a step-by-step approach to encouraging your plants to bloom. If the first method doesn’t work, move on to the second, and then the next until you achieve the desired result. As you’ll see, the proposed interventions are increasingly radical and reflect the growing desperation that many orchid enthusiasts are eventually experiencing:

0 – First, Do Nothing, at Least for a While

You need to give the plant time to adapt to your growing conditions, which are very different from those of industrial production environments. As the seasons change, the orchid should find its climatic landmarks and synchronize with them.

1- Reexamine Your Growing Conditions Rationally and Critically

Often, our home growing environments are deficient in light, which leads to a reduction in photosynthesis and a low buildup of reserves. The temperature difference between day and night is often very decisive for flowering. Since each species has its own requirements, you will need to consult reliable and relevant references to verify that your growing conditions are well suited.

2- Bring Your Plants Outside During the Summer to Stimulate Them With More Natural Growing Conditions

This should greatly invigorate your orchids. Outdoor climate diversity often proves to be the best flowering trigger. A column about the stay in the orchid garden should appear soon on the Lazy Gardener blog. We’ll talk about it again soon.

3- Practice Rhizome Pruning on Sympodial Orchids to Stimulate the Production of Young Tissue

This is a slightly more advanced technique that will be covered in a later blog post. In short, the rhizome of the sympodial orchid is pruned to remove plant tissue that is more than 2 years old (i.e., old leaves, old pseudobulbs, and old roots). Pruning should be done during the dormant period, i.e. just before new roots are produced. Pruning the rhizomes should induce a vigorous growth spurt and thus predispose the orchid to flower on the annual growth.

4- At This Point of Desperation, One Can Try to Induce Flowering With Chemical Additives.

Indeed, certain chemical products can be used by professionals to trigger flowering. Gibberellic acid is often used in the industrial production of Phalaenopsis, but this product is not available over the counter in Canada. On the internet, there are many “miracle” recipes to induce flowering, such as adding baking soda, crushed garlic in molasses, paprika, or other equally bizarre additives. On YouTube, there are some very entertaining videos on the subject, including one that recommends dissolving a Viagra tablet in a liter of water. According to this “flowering expert,” the plant would have a hell of an erection in the days that followed… If you choose to try this experiment, don’t tell your partner, who might be rather puzzled! 😉

To my knowledge, there is only one “general public” hormonal product authorized in Canada. It is marketed under the name “SuperThrive” and is said to stimulate the general growth of orchids, but flowering is not guaranteed. If you wish, try it and form your own opinion. Note that these hormonal stimulations are only effective if administered at the right time of year, in the right way, and on a well-cultivated plant that has accumulated sufficient reserves.

5- Finally, Get Rid of Plants That Never Flower

They probably aren’t suited to your growing conditions, which may be too far from the tropical conditions they originated from. It’s also possible that you bought a hybrid whose trigger genetics are so complex that it becomes nearly impossible to recreate its flowering stimuli in a home garden. Sorry to break your heart, but don’t waste your time with lame ducks. There are so many orchid species and hybrids that are easy to get to flower that it’s best not to waste your time with finicky varieties.

Editor’s Note

Mr. Charpentier’s columns on orchids are published on the Laidback Gardener website under a legal “Copyleft” model. Horticultural societies that wish to do so may include his columns in their technical journal or simply distribute the internet link to their members. However, please include the following statement:

This article was originally published in French on the JardinierParesseux.com website and in English on the LaidBackGardener.blog.