Basil is a sensitive herb that has very specific requirements for growing. Therefore it can be difficult to always take precautions before anything happens to the plant.
Sometimes, you may notice that your basil plant has leaves that are slowly turning translucent or transparent.
Transparent Basil leaves can be a result of serious problems in the plant such as root damage, nutrient deficiency, soil alkalinity, poor drainage, and so on.
This loss of natural green color in plants is called chlorosis.
Reasons for transparent basil leaves
1) Lack of sunlight
The epidermis is the outermost layer of a leaf. It is colorless, which is why we see the green color of the leaf inside. The green color is caused by chlorophyll, which is formed only because of sunlight.
When there is a lack of sunlight, chlorophyll is not formed and the leaves slowly lose their green color. They become light yellow first and then turn pale cream. Finally, they lose all color and become translucent or transparent.
To restore the production of chlorophyll, expose the plant to more sunlight gradually. Give the plant enough time to recover. Do not expose it to a lot of sunlight at once, as the plant may get stressed.
Initial exposure: In the first few days, expose the plant to just a few hours of indirect sunlight. Position the plant somewhere near a window in the early morning or late afternoon sunlight.
Gradual increase: As the leaves start to recover, expose them to long hours of indirect sunlight.
Recovery: As the plants recover, place them in normal sunlight. Basil requires at least 6 hours of sunlight daily.
If the plant has been damaged a lot, the transparent leaves can drop off the plant. This is not a matter of concern if the rest of the leaves stay healthy.
If it is not possible for your basil plant to get enough sunlight due to any reason, you can also invest in a growing lamp that is made especially for plants to provide them with an alternative light.
Insects with a proboscis that feed on plants can pierce the epidermis of the leaf and suck out the chlorophyll from the leaf, leaving translucent or transparent spots on the leaf.
In some cases, they can spread and do further damage.
Insects like spider mites, whiteflies, or aphids are found on the basil plant, sucking the juice out of the leaves.
They leave these tiny transparent spots on the leaves, which causes further damage and results in leaf stress and curling, turning brown, or just falling off.
Spider mites feed on the plant sap of the basil. Miticides or organic neem oil repellant works well against mites.
Insecticides for soft-bodied insects are good for getting rid of whiteflies. It is important to be careful as the leaves may contain traces of the chemicals in them.
Aphids suck the green out of basil leaves and stems. Nicotine sulfate and neem oil are some organic solutions to get rid of aphids.
You can also make a mixture of 5 tbsp of soap in one gallon of water and spray it on the leaves. Some farmers suggest cow urine.
Another solution is introducing ants, which are predators of aphids and other soft-bodied insects.
3) Cold drafts
A cold draft is a sudden current of cold air from the outside.
Basil is a tropical plant. A native to the tropical climates, basil thrives in warm, humid climates. From India, it was exported to the Mediterranean, and then to the colder regions of Europe and the USA.
That is why it doesn’t adapt to survive in very cold temperatures. In cooler climates, basil can grow indoors or at temperatures between 80 to 90 Fahrenheit (27 to 32 degrees Celsius).
As the natural environment of the basil is tropical, cold drafts can stress the basil plant. As a result, translucent spots appear on its leaves and soon they start turning transparent from the stress.
Cloche: To minimize the effect of cold currents, you can make use of a cloche. Enclose the basil in reusable plastic or a glass cloche or dome.
The cloche acts as a mini-greenhouse for the plant, serving as a barrier to cold drafts. It also keeps the air temperature around it stable.
It can be used on indoor plants as well as outdoors over fragile potted plants as a shield from frostbite.
Reposition: You can move the plant away from sources of drafts, such as doorways, windows, exhausts, vents, etc., and place them in a better-protected place.
Move to a warmer place: You can move the plant to a warm spot like the kitchen, back of a refrigerator, a heater, or a heat lamp.
Expose to sunlight: Make sure that the plant gets at least 6 hours of sunlight each day. Place the plant near a windowsill or door that serves the purpose.
Use artificial light: If direct sunlight is absolutely not possible, get a grow light for your indoor basils.
Basil is a plant that requires plenty of water but hates too much water. Overwatering basil can lead to a soft, mushy plant with translucent stems and leaves.
Overwatering leads to the rotting of the roots of the plant which also makes the plant rot. The first signs of the rot will be yellowish translucent leaves.
Not just overwatering, but too much moisture, in general, can turn the leaves transparent. When the soil is very soggy, the roots do not get the oxygen they require to breathe properly.
They start suffocating, which leads to papery translucent leaves which are dry.
Reduce the water you provide to the plant. Move the plant to a place of direct sunlight. Ensure that the soil is drained and the plant is dry before watering again.
Prune off the damaged leaves.
Use a planter that has drainage holes so that excess water flows out.
Basil can be infected with bacterial or fungal diseases that can be a reason for its leaves to turn transparent or translucent. Even indoor plants that are very carefully looked after can be infected with these diseases due to high humidity.
Leaf spot: If your plant has a disease called leaf spot, the leaves will have small translucent spots which grow bigger and have dark edges. The leaf begins to turn brown, black, or yellow.
There are several other bacterial and fungal diseases, for example, downy mildew, that can infect a basil plant.
You can ventilate the basil plants so that they get better air circulation.
A lot of this bacteria is spread through water and air. Make sure there is no backsplash on the leaves as you water the plants. Drip irrigation is a good option to prevent back-splashing.
Keep the plant dry as most bacterial and fungal infections are caused by too much humidity.
Try to get basil seeds that are certified to be free of infection. There are also varieties of basil that are resistant to such diseases, like the Genovese-type cultivars.
You can also use fungicides or bacterial sprays made at home.
6) Nutrient deficiency
A lack of necessary nutrients in the basil can also lead to transparent leaves.
Nitrogen plays a key role in the vegetative growth of the plant.
When a basil plant starts to experience nitrogen deficiency, the available nitrogen is provided for new growth, and the older leaves are ignored. If the plant is in its flowering phase, then the nitrogen is focused on the flowers.
This results in the lower leaves of the plant becoming translucent or transparent. Soon they dry up and die.
Fertilizers rich in nitrogen and amino acid supplements will increase the nitrogen content in your basil. Amino acids are a part of proteins that have nitrogen as one of the main components.
Basil is a tropical plant. In colder climates, it can be more susceptible to an iron deficiency. A deficiency of iron can stress out the basil plants causing the leaves to turn pale and translucent.
When the soil has high pH levels, calcium carbonate accumulates which can lead to iron deficiency.
Test the soil to ensure that there is an iron deficiency. The soil pH should be above 6.0.
Increase the acidity of the soil by adding an all-purpose soluble fertilizer or elemental sulfur. The amount will depend on the texture of the soil and the quantity of calcium carbonate in the soil.
Use a chelated iron fertilizer
You can also mix an organic fertilizer like animal manure. It increases natural chelates in soil, making more iron available to the plants.
For a quick solution, use a mixture of 1 gallon of water and 2 ounces of soluble ferrous sulfate powder. Spray the leaves with the mixture when the climate is cool, or in the evening, to prevent a leaf burn.
To avoid iron deficiency in the first place, add sulfur to the soil while planting and make sure the soil is well-drained.
What happens when the leaves turn transparent?
When the plant has lost a significant amount of chlorophyll, it loses its green color.
Chlorophyll is extremely important for a plant to make its food. It absorbs light which breaks down the water in the leaves into Oxygen and Hydrogen.
Without this green color, the plant cannot make its own food. The presence of translucent or transparent leaves indicates that the plant is slowly dying.