There are several reasons your basil plant may be dying, but the most common of these is that your plant is being either underwatered or overwatered.
Other possible reasons your basil plant is dying are pests, disease, lack of or too much light, and changes in temperature.
In this article, we will discuss all of these causes and how you can remedy each.
What are the causes of a dying basil plant?
The plant is underwatered
An underwatered basil plant will have crispy, wilted, and brown leaves. Some of its leaves may have dropped off into the soil around its base. This can happen if you forget to water your plant and allow its soil to become very dry.
Do not worry, because this is very easy to remedy. All you have to do is water the plant.
Bring the plant onto your patio or windowsill so that it is away from direct sun while recovering, and water the soil until it is sufficiently moist. The plant should perk up soon enough. Make sure you do not forget to water it again once the top of the soil feels dry to the touch.
If you see that the plant has started growing new leaves and is recovering well, you can place it back in your outdoor garden. Just be sure to check its soil every other day to be aware if it needs watering.
The plant is overwatered
Even though basil plants want their soil to be perpetually moist, that does not mean they will tolerate soggy soil. Their roots do very poorly in overwatered soil. If they have well-draining soil, it will be porous and airy enough to allow air to reach the roots. If the roots are constantly surrounded by damp soil, they will not get oxygen and will die. And if the roots die, they will not do their job of absorbing water and nutrients, which will eventually lead to the death of the entire plant. This condition is called root rot, and will make the plant more susceptible to fungal and bacterial problems.
Overwatering is not only due to you dumping excess water on the plant; it is also exacerbated by planting it in poorly-draining soil, a pot with no drainage holes or a pot that is too big, and not checking the soil to see if it needs to be watered.
An overwatered basil plant will have yellow leaves starting from the base, slowly spreading upwards. If it continues, the leaves will turn brown and drop off. If the soil is always wet, the roots will become soft and mushy and turn black. Rotten roots will smell just like rotten vegetation.
If an overwatered basil plant is too far gone, it may be unsalvageable, but if you are able to catch the problem early you can try to save it by letting the soil and the roots dry out and holding off watering for a few days. If the roots have parts that are black or brown, cut them off to save the healthy roots. Replant it in well-draining soil, in a pot with drainage holes.
If the root rot has affected the stem and leaves, it may be too late to save the plant so you are better off taking cuttings to propagate new basil plants.
The plant has pests
For basil plants in your outdoor garden, slugs are the major offender, while spider mites and aphids do the damage when you keep the plant indoors. These insects will feed on the sap of the basil plant, eventually depleting the plant and leaving it to die.
The first sign of these pests are spots on the plant’s leaves. A particularly bad infestation will leave the basil plant dehydrated and make it susceptible to other diseases because of its compromised state.
You can get rid of these insects with insecticides. Make sure you keep the affected plant away from your other plants so that they do not become affected while it is being treated.
The plant is diseased
One of the most common diseases that afflict basil plants is fusarium wilt. This is a group of fungi that affects plants. This fungus will attack the xylem vessels by blocking them and preventing the transport of water and nutrients in the plant. The signs to watch out for include yellow and wilted leaves, rotten stems, and stunted growth.
There is no salvaging a plant afflicted with fusarium wilt. The best you can do is prevent your other plants from getting it and make sure you dispose of it properly. Dispose of the soil as well and make sure you wash and disinfect the pot well before reusing it.
The plant is not getting enough light
Another reason your basil plant is dying could be that it is not getting the amount of sunlight that it needs. Basil plants need to be placed either under the full sun or at least near a window.
They need six to eight hours of sun every day, or twelve hours of artificial light when they are indoors during the winter.
Basil plants that do not get enough light will become leggy because they will grow toward the nearest source of light, but the leaves will be smaller than normal.
Changes in temperature
Basil plants are native to the tropical parts of Asia, so they will not do well in cold weather. Temperatures below 50 degrees Fahrenheit will cause stress and wilting. If your plant is grown indoors, it is less likely to be affected by temperature changes because the temperature inside the house is more stable. If the plant is outside, make sure you bring it inside when the night temperatures get lower than 50 degrees Fahrenheit.
Conclusion
Your basil plant is most probably dying because of improper watering techniques. It is either being underwatered or overwatered.
Other common reasons for basil plants dying are pests, disease, insufficient light, or stress from changes in temperature.
Basil plants are hardy plants that are very easy to grow, and as long as you give them the basic care they will grow happily and healthily.
Image: istockphoto.com / Octavian Lazar