Many people love the glossy and unusual foliage of an Anthurium, but if your Anthurium is refusing to flower, you might be feeling a little frustrated. Anthuriums have very unusual flowers, and most owners want to see these from time to time.
Quite a few things can stop your Anthurium from producing those astonishing and unusual blooms, and these include insufficient lighting, wet soil, poor soil, temperature and humidity problems, lack of fertilizer, and compaction. Any of these or a combination of several could stop your Anthurium from producing flowers.
Cause One: Insufficient Lighting
This is one of the biggest issues that can stop an Anthurium from flowering, and unfortunately, it’s a really common one. That is because it’s pretty hard to get the lighting conditions for an Anthurium exactly right, and if they aren’t right, it will not flower.
An Anthurium needs bright light, but will not tolerate direct sun. These plants originate from tropical rainforests, and that means there is usually plenty of light available to them, but it rarely falls right on their leaves because there is a whole canopy overhead that shades them.
Reproducing these conditions in the home can be a challenge. If your Anthurium is getting too much light, its leaves are likely to burn. Brown spots will appear where the foliage gets damaged, and this will stress it out and stop it from flowering.
On the other hand, with too little light, it will simply not have enough energy to produce flowers. You may find that its foliage is pale and leggy, but in some cases, your Anthurium will look fine – it just won’t flower. Poor lighting is the first thing to look for if your Anthurium never blooms.
How To Fix It
First, determine whether your plant needs more or less light. It’s very common for a lack of flowers to be due to shadiness, so you will probably be looking to move your plant to a brighter spot. Assess your whole home and try to find somewhere that offers good light.
You may be able to move your plant closer to a windowsill or put it in a sunnier room. Don’t put it on a south-facing windowsill in the middle of summer, as it may burn, but if you have a table in a south-facing room, this may be suitable.
If you really can’t increase the natural light your plant gets, consider whether it would benefit from being given a grow lamp. This can supplement the natural light and is a great way to deal with unsuitable conditions without any risk of burning your plant’s leaves.
Remember to turn the light off at night, so your plant gets a period of darkness. It needs this, or it will become stressed.
If you need to put your Anthurium close to a window where it is at risk of burning, try putting up a thin curtain. You can open the curtain when the weather is cloudy and the light dimmer, and close it to offer your plant some protection when the sun is hot. Hopefully, correcting the light conditions will encourage your Anthurium to flower.
Cause Two: Watering Problems
If you over-water or under-water your Anthurium, you are likely to stress it out and stop it from getting all the nutrients it needs. Anthuriums take nutrients up with water, so if there is too little water in the container, they won’t be able to access them. On the other hand, if there is too much water, the roots may rot, and will also lose access to nutrients.
Water stress will stop your Anthurium from flowering because it won’t have enough nutrients. When plants are lacking in nutrients, they tend to focus on leaf growth because this gives them access to energy from the sun. They don’t develop flowers, because they are not in a good enough position to try to reproduce.
It’s, therefore, crucial to ensure that your Anthurium gets the right amount of water if you want to see flowers.
How To Fix It
You need to balance your plant’s watering needs with care. Check how wet the soil is before giving the plant a drink. If it is still wet to an inch below the surface, your Anthurium does not yet need a drink. However, if the soil has dried out and the plant is starting to wilt, it would benefit from some water.
Try not to let your plant spend too long in one extreme or the other. Very inconsistent watering will cause stress. Anthuriums come from stable rainforest environments, where they almost never get dry. Too much water can certainly be dangerous, but repeated droughts will leave this plant stressed and sickly.
You may be able to work out an approximate watering schedule, but don’t stick to it too rigidly. Changes in the seasons will affect how quickly the water evaporates from your plant’s pot and alter how much it drinks. Base your watering on the feel of the soil, but set yourself regular reminders to check this.
Cause Three: Poor Soil
Your Anthurium will struggle to produce flowers if it is not growing in a suitable potting medium. Some people make the mistake of planting their Anthuriums in standard potting compost. This is understandable since most plants grow in this, but aroids will struggle.
The potting mix will be too heavy, which will cause several problems. It will restrict oxygen access by the plant’s roots, causing it to stress, and will also cause water to pool around the roots. Waterlogging, as mentioned above, will stop your plant from accessing key nutrients and prevent it from flowering.
If it is kept in the wrong potting mix for an extended period, your Anthurium is likely to get progressively sicker and less capable of producing flowers. A weak plant will not bloom.
How To Fix It
You will need to transfer your Anthurium to a more suitable potting mix. Usually, these plants prefer to grow in either a commercial mix designed for aroids, or in a homemade mix of peat moss, orchid bark, and worm casts.
The sooner you can swap your Anthurium to a suitable potting compost, the better. Tip it out of its current container, and if the roots are soggy, give them some time to air dry. Source a container with good drainage holes, and half fill it with a suitable growing medium.
Place your Anthurium in it and top up the growing medium around its roots until they are buried. It will probably take some time to adjust to the new environment, but this should hopefully lead to flowering, even if it takes a little time.
Cause Four: Temperature And Humidity Problems
Stress of any kind can make your Anthurium less willing to flower. It will be focusing its resources on survival if the environment is not ideal, rather than on reproduction. To switch its focus, you need to ensure that conditions are as suitable as they can be.
As tropical plants, they like both warmth and humidity, and they will struggle if the temperature drops or the air gets too dry. You should be monitoring both conditions to ensure they stay suitable.
You can use a thermometer to keep an eye on temperature and a hygrometer to keep an eye on humidity. Anthuriums prefer temperatures between 65 and 80 degrees F, and humidity levels of 50 percent or higher. If either level falls below the minimum, your plant will start to struggle. Ideally, temperatures should be 70 degrees F or higher.
Keep an eye on both of these factors if you are confused about why your Anthurium isn’t flowering. You may also notice that its leaves will suffer if either of these measurements is wrong.
Cold temperatures will cause leaf blemishes, shriveling, and loss of foliage, while lack of humidity can make the leaves dull, stealing their glossiness. Both issues are signs that your plant is stressed and not being given the conditions needed to promote flowering.
How To Fix It
Both temperature and humidity problems can be fixed relatively easily, so let’s start with temperature.
If your Anthurium is stored in a cold place, such as a porch or conservatory, consider moving it into the main house. It doesn’t want to be directly beside a heater (this will kill it extremely quickly), but it will benefit from being in a warm room that is free from drafts.
The more stable you can keep the temperature, the more likely the plant is to flower. Aim for 70 degrees F or higher during the day, and no less than 65 at night if this is feasible. Warmth should encourage blooming.
Next, let’s look at humidity. You can mitigate humidity issues by putting your Anthurium in your bathroom so that the steam from the shower mist it, or you can get a plant sprayer and mist the leaves and soil a few times a week. This will increase the humidity levels around the plant.
If you would rather not mist your Anthurium by hand, try installing a plug-in humidifier.
If you go for the humidifier, don’t forget to turn it off in the afternoon, so that the plant doesn’t get too wet when temperatures drop during the night.
Both of these things should help to encourage your plant to flower. Make sure your Anthurium doesn’t get too hot or too wet, however, as these will cause other issues that may deter it from flowering.
Many people find that having a fan nearby ensures the Anthurium doesn’t stay wet for too long. You should never direct this at your plant (Anthuriums do not like strong breezes), but keeping the air in the room moving will reduce the risk of fungal infections.
Cause Five: Lack Of Fertilizer
Plants need nutrients if they are to build flowers, just as they need nutrients to grow at all. If your plant finds that nutrients are in short supply and it is struggling to get them, it will put its focus into leaf production instead, and will not make any flowers.
It’s easy for this to happen if you don’t have a regular fertilizing routine, especially if you haven’t repotted your Anthurium for a while. The plant will deplete the nutrients in its container fairly quickly, and will then struggle to find enough to make flowers.
In the wild, Anthuriums gather nutrients from trace minerals and decaying leaves on the trees that they usually grow on or near. They can pick them up from rainwater, and they generally have a constantly renewing supply. The amounts are small, but the delivery is regular.
Mimicking this setup at home may help to encourage your Anthurium to produce blooms because it will have plenty of food to dedicate to its growth.
How To Fix It
Fertilizing your Anthurium regularly is important. You may not need to do so for a couple of months after it has been repotted, but at other times, you should be fertilizing it throughout its growing season in the spring and summer. Cut back on or stop fertilizing it during the winter.
You can use an all-purpose liquid fertilizer or one that is high in phosphorus. Phosphorus is particularly associated with flower growth, and having an abundance of this nutrient may encourage your Anthurium to produce new blossoms.
Dilute the fertilizer before applying it, and then add some to the soil. You can either dilute it to around a quarter of its usual strength and apply it approximately once a month, or dilute it further, to around ten percent, and apply it weekly or every two weeks.
Whichever you do, avoid splashing the leaves or stems with fertilizer. You should soon see new growth and hopefully, flowers appearing. Make sure you don’t go overboard with the fertilizer; too much will burn your plant’s roots and may stress it out. This will stop it from producing flowers.
Cause Six: It Needs Repotting
Anthuriums like to be somewhat root bound, and they will often grow their roots into every part of the pot before the container needs changing. However, this can cause problems. If the Anthurium is not repotted fairly frequently, the growing medium may compact around its roots, reducing the oxygen supply.
This may not directly prevent your plant from flowering, but it will cause it stress and lower the chances of it focusing on bloom production.
Since wild Anthuriums grow almost entirely in the air, often with their roots only lightly covered by moss, they struggle when the oxygen is restricted. Compaction may also result in waterlogging because the condensed potting medium will trap the water more easily.
You may be able to see if this is happening because the roots will start to protrude from the pot, the soil will become denser and harder, and water may start to pool on the surface. It might become more difficult to push your finger into the growing medium when you try to check whether your Anthurium needs water.
How To Fix It
The best way to fix this is to repot the plant. Even if your Anthurium hasn’t grown out of its current container, aim to repot it every couple of years. This will aerate the roots and loosen up any compaction.
You can use the same container or a slightly bigger one, depending on the size of your plant’s root ball. Either way, you should change the growing medium for some fresh bark and worm casts, as this will refresh the nutrients and reduce the risk of pests or diseases invading the soil.
Tip your Anthurium out of its current container, and take a few minutes to inspect the roots and check that they are healthy. Brush off the remaining soil, and tease out any roots that are getting very tightly wound around other ones if you can.
Next, start filling your new container, or wash and reuse the old one. Make sure you are mixing plenty of drainage material through the potting medium, as this will often help with aeration too. Don’t compress the mixture, but instead loosely shake it into the pot and only pat it down lightly.
Put your Anthurium in place and fill the pot with the remaining growth medium, and then water it. Your Anthurium should now have noticeably better airflow around its roots, which may help it to get more oxygen and produce flowers.
It’s often difficult to determine why an Anthurium isn’t flowering, and you may have to try several different approaches in order to coax yours into blooming. Check all of the conditions above, rather than just one of them, and keep adjusting the environment until you have got it perfect. Hopefully, your hard work will be rewarded by some of this plant’s spectacular flowers!