Orchids: can molasses help them produce new flowers?

Do your orchids remain green yet refuse to produce new flowers? An ingredient kept near the baking tins may help support them.

An orchid that does not flower again is not necessarily unhealthy. In many homes, it is more likely to lack suitable light, a small difference between daytime and night-time temperatures, or available nutrients. Among the tips tried by houseplant enthusiasts is using molasses, a thick brown syrup, heavily diluted in watering water. This should only be an occasional treatment: once a month is more than enough.

Molasses provides useful elements for orchid roots

Made during the processing of sugar cane or sugar beet, molasses is best known as a culinary ingredient. Its rich consistency and distinctive flavour make it popular in certain sweet recipes. It also contains potassium, magnesium and some trace elements.

These elements may be useful for orchids, especially Phalaenopsis, which are very common in flats. Potassium contributes to the overall strength of plant tissue and supports the development of flower spikes. Magnesium is involved in chlorophyll, the pigment that enables leaves to capture light energy.

“Molasses is not a substitute for light, controlled watering or suitable fertiliser. It can only be an occasional addition when the plant is in good condition.”

The sugars in this syrup may also feed certain micro-organisms in the growing medium. In a healthy, well-aerated bark mix, this activity may make some nutrients more readily available around the roots. It should not be regarded as a foolproof method: an orchid will not bloom simply because it has received sweetened water if it lacks light or if its roots are suffocating in a waterlogged pot.

The right dilution to avoid damaging the plant

Caution matters more than quantity. Molasses is concentrated and sticky. Pouring it neat into the pot can upset the balance of the growing medium, cause fermentation smells and attract insects.

To try it, use extremely small amounts. A straightforward mixture can be prepared with room-temperature water and a little syrup.

• Pour 240 millilitres of water into a clean container or spray bottle.
• Add half a teaspoon of molasses.
• Stir thoroughly until the water is evenly mixed.
• Moisten the growing medium around the base of the plant, without spraying the flowers.
• Repeat no more than once a month.

Another commonly used guideline is not to exceed one teaspoon per litre of water. If there are several orchids in the home, it is better to make only a small amount of solution and share it between the pots. The mixture does not store well: the sugars may ferment, especially in warm conditions.

Water only when the roots are already slightly moist

Avoid pouring this enriched water onto a completely dry growing medium. Dry roots absorb rapidly, which can make the treatment too sudden. Watering normally the previous day, or soaking the plant in clear water for a few minutes, prepares it first.

Afterwards, always allow the pot to drain. An orchid should never sit in a saucer filled with water for an extended period. Its roots need moisture, but they also need air. When they remain submerged, they turn brown, become soft and can no longer do their job.

Signs that mean you should stop

A plant does not always respond well to homemade treatments. After applying molasses, keep an eye on the pot over the following days. A sour smell, a slimy surface or a white deposit are warning signs that should be taken seriously. Small gnats around the growing medium are also a reason to stop adding sugary treatments.

“If the growing medium becomes sticky or smells of fermentation, rinse it with clear water and leave several weeks between any fertiliser applications.”

To rinse an orchid, put the pot in the sink and run lukewarm water gently over the bark for one or two minutes. Then let it drain completely. This also helps remove mineral salts that can build up after repeated watering with fertiliser.

Fragile orchids, recently repotted plants, unwell plants, or those affected by mealybugs are not suitable candidates for this sort of trial. It is better to deal with the main problem before adding any supplement.

Habits that genuinely encourage the next flowering

Molasses can complement a routine, but it cannot replace one. To encourage a new flower spike, growing conditions matter far more than an ingredient added once a month. A bright windowsill, away from harsh midday sun, is often the best position.

Phalaenopsis also benefit from a modest drop in night-time temperature for a few weeks, often around 4 to 6 degrees lower than during the day. This variation can encourage a flower spike to appear. In a home that is heated continuously, moving the plant to a slightly cooler room overnight can help, provided cold draughts are avoided.

• Check the roots through the transparent pot: green roots are still moist, while silvery-grey roots need water.
• Water with soft water when the growing medium is almost dry.
• Apply very diluted orchid fertiliser during periods of growth.
• Cut off a dried flower spike with a clean tool, without touching healthy leaves.
• Repot every two to three years in fresh bark if the mix is breaking down.

Be cautious with other kitchen remedies

Rice water, eggshells and banana skins are often mentioned in gardening advice. However, they all require considerable care. Plant matter buried in bark breaks down quickly and can encourage mould. Crushed eggshells release their elements very slowly and do not always meet the plant’s immediate needs.

Molasses has the benefit of being easy to measure, provided you choose a plain version without flavourings or unnecessary additions. One monthly trial, combined with adequate light and careful drainage, is enough to monitor the orchid’s response over the weeks. A firm leaf, fleshy roots and a green tip emerging near the base remain the best indicators that the plant is returning to its natural rhythm.