If you have hibiscus plants in your garden, you may notice that some of them are producing buds but not opening. This can be quite frustrating to see as the plant is so beautiful and seems healthy on the outside.
But if this is happening to your hibiscuses, don’t worry! We’re here to give you some helpful tips about what could be causing it and how to fix it.
Why Are My Hibiscus Buds Not Opening?
The most likely reason for hibiscus buds not opening is that they haven’t received enough sun or are stressed. This is what I have noticed from my own experience as a novice hibiscus grower.
However, there are other reasons for the buds not to be blooming. For example, pests could be damaging the buds from the inside. This is why it’s important to check all buds before they bloom to keep your garden free of pests.
I will now jump into 8 reasons for this issue. By the end, you should hopefully be able to identify why your hibiscus buds are not opening and what you can do about it.
1. Not Enough Sun or a Lack of Warmth
Hibiscus plants need plenty of sun and heat in order to bloom. If you notice that your plant is not blooming, check the amount of sunlight it receives each day.
Make sure that there are no large trees around blocking any part of the plant from the sun either.
Another reason for this issue could be that the plant is too cold. The minimum temperature for your hibiscus to grow and bloom well will depend on what type of variety it is, but anything below 15Â°C (59Â°F) should not be tolerated by them at all.
If you live in a place where the weather gets quite chilly during autumn and winter, you should be more aware of your hibiscus’ situation.
2. The Hibiscus Plant Is Under Stress
If you notice that your hibiscus plant is not blooming and the buds aren’t opening, then it could be because of some form of stress.
Trying to identify the source of this stress can be difficult but it could be due to pests, weather conditions, cold drafts, or even from transporting if you recently moved home.
If your plant is under any form of stress, there’s a chance that no buds will open for some time until things get back to normal.
You should look out for signs like discoloration or wilting leaves and try to fix whatever is stressing out your hibiscus.
3. The Soil Is Holding Too Much Water
If the soil is too wet for too long, it could cause buds not to open on your hibiscus because of rot.
Overwatering or poor draining can quickly lead to root rot and other conditions that will stop flowers from forming correctly.
It’s best to water pots moderately so you don’t over-saturate the soil and let it fully dry out between watering.
If you’re not sure whether your hibiscus plant is getting too much or too little water, check the soil by sticking your finger down into the soil – if it’s moist, don’t water. If it’s dry, you can give them some water until they drain out of the pot.
4. Too Much Phosphorous in the Soil
If your plant is not blooming, it could be because of too much phosphorus in the soil. This can easily happen if you use fertilizers with high phosphorous levels on them regularly.
Phosphorus prevents nitrogen from entering plants and stops flowers from opening up properly. A solution to this would be to switch over to fertilizers that have a high nitrogen content instead.
If you are unsure about the levels of phosphorus in your soil, it might be best to get some testing done by an expert or to have a look at the ingredients list of your fertilizers.
5. Too Much Nitrogen in the Soil
If your hibiscus is not blooming, it could be because of too much nitrogen in the soil. This can happen if you use fertilizers with high levels on them regularly or over-fertilize the plant by mistake.
Having too many nitrates has a similar effect to phosphorus, stopping flowers from opening up properly and stunting growth.
If you are unsure about the levels of nitrogen in your soil, it might be best to get some testing done by an expert or to have a look at the ingredients list of your fertilizers.
6. Pruning Incorrectly and at the Wrong Time
It’s important to prune hibiscus bushes during the right time of year. If you prune them too early, it could shock the plant into not producing buds or blooms at all for that season.
If you are unsure about this, it’s best to leave the job to a professional and get some advice on when they think is the right time for your plant.
7. The Pot Is Too Small or Large
If you have a hibiscus plant in a pot that is too small, it could stunt its growth and cause buds not to open.
There’s no harm in using large pots for your plants as long as they are well-draining and don’t keep the soil wet at all times. If there’s ever standing water or moisture in the soil, it could cause problems for your hibiscus blooms.
8. Pests Are Attacking the Plant (Thrips)
Hibiscuses are very susceptible to pests and this is why it’s so important to check all new growth on a regular basis. If you find any signs of an infestation, act immediately before they spread further into the plant.
Thrips – These will eat away from inside the buds and cause them to open very slowly or not at all. You may notice that you have them if there is a lot of black dust on your leaves, which means they have been producing dark fecal matter while eating.
You can treat thrips with neem oil (Amazon link), which is a natural pesticide made from the neem tree.
In conclusion, there are many reasons why your hibiscus plant might not be blooming. If you have noticed any of the signs mentioned above, take a look at what could be causing it and treat accordingly to help improve these issues for next year’s crop.
I hope this blog post has been helpful and I wish you all the best for growing your hibiscus plants this year.
Tim is an avid gardener from the UK. He was the founder of PlantCarer.com from 2021 to Sep 2023. He sold PlantCarer.com to Aaron. He has since started his own business called Seed To Supper, which provides new gardeners all the materials you need in a box (pots, seeds, compost and instructions) to grow your own delicious and nutritious vegetables and herbs from start to finish – no garden required.