The arrowhead plant is a vining or trailing plant that is native to South America and Mexico. Its aesthetic has gained it much popularity over recent years, especially as a hanging plant.
This plant gets its name from the shape of its leaves which, when young, emerge in the shape of an arrowhead. As the leaf matures, however, it becomes lobed. The color of the leaves also changes with maturity. During different stages, they can have bright pink, lime green, dark green, or even white hues.
Because the plant’s natural habitat is tropical, it does not do well in cold weather. If you live in an area with cold winters, you are better off growing it indoors.
One of the most common problems experienced by arrowhead plant owners is yellowing leaves on their plant. This change in color is due to an environmental factor causing the plant stress. Such factors include underwatering, overwatering, too much sunlight, poor lighting, lack of nutrients, incorrect soil pH, temperature changes, low humidity, pests, and natural aging.
In this article, we will discuss each of these possible causes of yellowing leaves and what you can do to fix each one. So, if you are facing a similar problem and wish to learn more, just keep on reading.
Why are the leaves on my arrowhead plant turning yellow?
Not enough water
If the leaves on your arrowhead plant are turning yellow, drying out, and becoming crispy, it is possible that you have not been giving it enough water. Consistent underwatering will cause your plant to dry out, turn yellow, and become very limp over time due to dehydration.
You will be able to tell that the plant is underwatered if you poke your finger two inches into the soil and you feel no dampness or moisture.
If you suspect that your arrowhead’s yellow leaves are the result of underwatering, water the plant immediately. Keep pouring water over the soil until you are sure that all of the soil has been generously soaked; then let the excess water drain out through the drainage holes at the bottom of the pot before placing the plant back in its usual spot.
Sometimes, if a plant has been dehydrated for too long, the soil becomes so dry and compact that it repels water, making it impossible to rehydrate the plant or the soil from the top. If this is the case, you will have to bottom-water your plant. To do this, place the pot in a shallow basin filled with about three inches of water. Leave the pot in the water for 10 to 15 minutes, so that the thirsty soil and roots can absorb the water through the drainage holes at the bottom of the pot. After 10 to 15 minutes, remove the pot from the basin and leave it on a rack to let the excess water drip out for a few hours. When all of the excess water has drained, you can replace the plant in its usual spot.
After three to four cycles of either top watering or bottom watering, you should see signs of recovery in your underwatered arrowhead plant.
Too much water
The most common reason arrowhead leaves turn yellow is from overwatering. This can happen as a result of giving the plant too much water every time you water it, watering it more often than necessary, using poorly-draining soil or pots, or not adjusting your watering habits to changes in the weather, season or climate.
If the soil around your plant retains too much water, it will become soggy and waterlogged, which is not a suitable environment for arrowhead plants: they prefer their soil to dry out a little between waterings.
Constantly wet soil increases the risk of root rot. Furthermore, a compromised root system is unable to absorb the nutrients, minerals and water necessary for the plants’s healthy growth. When the roots are in trouble, yellowing of the plant’s leaves is a common symptom.
If you think your arrowhead plant is overwatered, stop watering it immediately and place it in a spot where it can get lots of bright, indirect light to help the soil dry out faster.
If you suspect root rot, you will have to remove the plant from its pot to check the roots. After unpotting it, shake or wash off as much soil from the roots as possible. Then, inspect the roots for sections that are brown or black; these are rotten and must be removed. Use a sterile pair of scissors to prune them away until only healthy, white roots remain.
Place the plant on a dry, flat surface and let the roots air-dry for a few hours.
Choose a new pot that has drainage holes at the bottom and fill it halfway with a well-draining potting mix. Place the plant in the pot and cover the roots with more soil.
To avoid overwatering in the future, always check the soil’s moisture level before watering the plant. To do this, poke your index finger into the soil, and if the top two inches of soil are dry to the touch, you can water the plant. If the soil is still damp, wait one or two days before checking again.
Too much sunlight
When it comes to lighting requirements, arrowhead plants are extremely adaptable. For short periods, they can tolerate a variety of conditions. However, they do best with bright to moderate lighting, and their leaves can become scorched and yellow if exposed to direct sunlight for extended periods.
If you notice your arrowhead’s leaves turning yellow and suspect sun exposure to be the culprit, move the plant to a different, shadier location. Place it near a window that gets bright, indirect sunlight, rather than any direct light. An east-facing window is ideal.
If the only window available in your home lets in harsh light, you can still place your plant there, but hang a sheer curtain over the window to diffuse the light’s intensity.
Although the arrowhead plant prefers indirect light, this does not mean you can keep it in low light conditions for too long, either. Plants always need a light source because this is how they create food and energy for themselves to keep growing and surviving.
If you deprive the plant of its required light, its leaves will turn to a pale yellow color and become duller. It will also have stunted growth and the entire plant may start to droop.
A plant that does not get enough light can also become leggy as it starts to grow and lean in the direction of the nearest light source.
If you think your plant is not getting enough light, gradually expose it to more and more light every day in a sunnier spot. Make sure the plant still only gets indirect light, though, because you don’t want it to be scorched, either.
Rotate the plant 30 degrees every couple of days so that all sides get their fair share of light and the plant grows symmetrically.
Lack of nutrients
Arrowhead plants are only moderate feeders, and will develop stunning foliage if they receive the proper fertilizer and good care.
The yellowing of arrowhead plant leaves can be a sign of nutrient deficiency.
The plant needs nitrogen, magnesium, phosphorus, and other essential nutrients, all of which can be found in most commercially available houseplant fertilizers.
Fertilize your arrowhead plant once a month during its growing season, which is the spring and summer. It is best not to fertilize it during the fall and winter, as this is when the plant is dormant and does not need extra nutrients for new growth.
Arrowhead plants prefer slightly acidic soil. In alkaline soil, their roots will not be able to absorb iron very effectively, and iron is essential for photosynthesis and chlorophyll synthesis. Because chlorophyll is the pigment that gives plants their green color, if the plant cannot produce the pigment, its leaves will turn yellow.
pH aside, these plants like their soil fertile, breathable, and well-draining. They will lose their leaves if the soil has poor drainage or permeability, or if it is alkaline. Replace your plant’s soil every one to two years, and add ferrous sulfate to the soil to acidify it if it is too alkaline.
Arrowhead plants grow naturally in subtropical and tropical environments. The good news is that they can also be grown in indoor environments as houseplants, but keep in mind that they are extremely sensitive to temperatures below 50 degrees Fahrenheit.
Aside from that, high temperatures can cause sunburn and yellowing leaves on these plants. In order to grow arrowheads successfully indoors, the room temperature should remain between 60 and 85 degrees Fahrenheit. Temperatures below or above this ideal range will compromise the vibrant green colors of the foliage.
You could invest in a digital thermometer to help you monitor the temperature in the room where you keep your plant. It is also important to keep it away from any source of heat, such as heating vents, to prevent the foliage from being burned.
The arrowhead plant likes humid conditions that simulate the warm, moist environment of its natural habitat. A high level of humidity in the room where it is kept will help keep any leaf problems at bay.
The plant’s leaf tips and edges will become yellow or brown if the humidity is too low. This is because dry air will remove the moisture from the leaves, leading to the discoloration. The leaves may droop and turn yellow on both sides before eventually turning brown.
If your climate is not very humid, mist the plant’s leaves two to three times per week so that they do not dry out as fast. It may be a good idea to keep the plant in the bathroom or kitchen, because these rooms are the most humid. Just be sure that, if you place it in the bathroom, it can still get the light that it needs.
You can also place the plant’s pot on a tray filled with pebbles and water, so that as the water evaporates from the tray, it moistens the air around the plant.
Finally, if you have the means, you can buy a humidifier to regulate the humidity in the room where you keep your plant.
Arrowhead plant leaves are highly susceptible to mealybugs and spider mites, which can cause significant damage. Pest infestations can also result in yellowing foliage.
Spider mites are well-known for sucking the sap from the cells of plants’ leaves. This depletes the leaves of nutrients and moisture. The yellowing is caused by the holes on the leaves left by the pests where they fed.
Before you start to treat your plant for any infestation, move it to a different part of the house to keep it quarantined from your healthy plants.
A simple way to kill the pests is to use either neem oil or rubbing alcohol. Soak a cotton pad with either of these and wipe down the affected areas of the plant. Repeat the treatment every three days until you are sure that all of the pests have been removed.
Natural aging of the plant
If you have gone through all of the reasons above and none of them seem to apply to your arrowhead plant, it is possible that its yellowing leaves are simply due to natural aging.
It is completely normal for your plant to shed some of its older leaves as it concentrates on producing new growth over time. These older leaves will first turn yellow and then fall off the plant.
If the rate of yellowing is quite slow, it is nothing to be concerned about and is simply a normal part of the shedding process. Keep an eye on how frequently they are turning yellow, though, because if the rate accelerates, it may be necessary to inspect the plant once more for the issues discussed above.
Arrowhead plant care
The arrowhead plant prefers bright, indirect light, and direct sunlight should be avoided. Because harsh rays can burn or bleach the delicate leaves of the plant, diffused light is the best option. Those with variegated color patterns can withstand a little more direct sunlight, whereas those with darker green foliage are better suited to partial shade.
Plant your arrowhead plant in a traditional, soil-based potting mix to give it a strong foundation. Because arrowhead plants are prone to root rot, you should make sure that whatever soil you use is well-draining. Additionally, consider planting it in a terracotta or clay pot to help wick away any excess moisture from the soil.
Water your arrowhead plant on a regular basis during the spring and summer months, and reduce your watering frequency during the winter months. Allow the soil to dry out partially between waterings, but never let it dry completely. Similarly, the soil should never be soggy because this increases the chances of root rot which can kill the plant if not treated immediately.
Temperature and humidity
The arrowhead plant prefers warm, humid conditions consistent with its tropical habitat. As much as possible, try to keep the temperature around it above 60 degrees Fahrenheit.
While the plant can withstand average humidity, it will thrive if there is additional moisture in the air. Consider putting your plant in a part of your home where there is naturally higher humidity, like the bathroom or kitchen. You can also use other methods of increasing humidity such as a humidifier, or a water pebble tray beneath the plant’s pot.
Support your plant’s growth by feeding it with houseplant fertilizer once a month during the spring and summer. During the winter, when the plant’s growth naturally slows, stop feeding it.
The arrowhead plant is a popular houseplant that is low-maintenance and easy to grow.
It is native to South America and Mexico, and prefers living conditions that simulate its tropical natural habitat.
This plant gets its name from the shape of its leaves when they are young, which resemble arrowheads; however, as the leaves mature they become more deeply lobed.
One of the most common problems encountered by arrowhead owners is when their plant’s leaves turn yellow. The possible causes of this are not enough water, too much water, too much sunlight, poor lighting, lack of nutrients, temperature changes, overfertilization, low humidity, pests, and natural aging.
The sooner the exact cause of the problem is determined, the faster the issue can be resolved and the plant can return to full health.
Image: istockphoto.com / Jamaludin Yusup