Why Are My Basil Leaves Turning Yellow, White or Silver? (Overwatering? Read This First!)

As a gardener, I always seek answers to my plant problems. But this one was puzzling me: my Basil leaves were turning white!

First of all, let me just say that I love Basil. It’s one of my favorite herbs, and I use it in almost everything- from pesto to soups and even cocktails. So when my Basil started turning white, I was worried.

I researched how to fertilize Basil plants but became more confused the more I studied. I didn’t know what to do! I kept on researching and this is what I found.

If your Basil leaves are turning white, it is most likely caused by a lack of nitrogen in the soil, fungus, excessive direct sunlight, or overwatering.

How Do I Make My Basil More Green?

Sometimes Basil plants may develop white, yellow, or silver leaves. This can alarm new gardeners or those who have never grown Basil before.

If you notice that your Basil plant has any of these symptoms, it is crucial to take action immediately to prevent further problems with the plant.  

Why are my Basil Plant Leaves Pale and Losing Color?

Basil seedling
The short answer is usually a nutrient deficiency. Nutrient deficiencies occur when the plant is not given enough nutrients through soil or water sources. This will cause yellowing leaves at first, turning them into white and potentially other silver and speckled discoloration patterns.

The most common nutrient deficiency in Basil is lack of nitrogen. So if your plants look droopy or yellow, it’s probably because they’re not getting enough nitrogen. 

Here are some quick tips to improve nutrient deficiency:

  • Add some compost or manure to the plant’s soil. This will help replenish the nutrients your plant needs to grow strong and healthy.
  • Try fertilizing with fish emulsion or seaweed extract, two other great options for increasing the amount of nitrogen in your garden soil. Just ensure not to overdo it- too much fertilizer can cause problems too.

If you’re new to growing Basil, nutrient deficiency is a common mistake- especially if you’ve purchased a small starter kit at the store (which may not include nutrients). Your Basil plant needs nitrogen and potassium to grow healthy, dark green leaves.

What Does Basil Fungus Look Like?

Fungal diseases like powdery mildew or anthracnose can affect Basil plants and cause them to turn yellow or white overnight. These diseases come from many factors, including too much sun exposure (or lack thereof), poor air circulation around the plant, or overwatering.

To detect fungal disease in Basil plants:

  • Look for signs of wilting or discoloration in the leaves or stems. 
  • Check under leaves and stems for spots that look like mold growth or white powdery residue.
  • Spray water onto leaves, stems, and flowers to see if any white residue appears; this may indicate the fungal disease is present. 

If your Basil plant has any of these symptoms, you can try treating it with an antifungal spray. You can also try moving your plant to a dryer location, as excess moisture is a common cause of fungal disease in plants.

Make sure you use clean containers for your seedlings when transplanting your Basil plants into their final homes. Fungal diseases thrive when there is too much moisture in the soil or around the plant roots. It is important to avoid overwatering.

Does Basil Like Full Sun?

Planting Basil
Take a look at how much sun your plants are getting. Basil plants thrive in full sun conditions but can also tolerate partial shade.

Too much exposure to sunlight causes them to turn pale or yellowish-green and develop wilting toward the tip of their stems. If this happens, move them away from direct sunlight until they recover entirely (or move them back indoors if possible).

If your Basil plants are growing in containers and their leaves are turning yellow or white, it’s probably due to too much sun exposure- Basil plants need shade during hot months (especially if they live in full sun).

How Do You Know If You Are Overwatering Basil?

Basil plants are susceptible to overwatering. Basil likes to be kept moist but not sopping wet. If your plant is soggy and drooping, check its roots and ensure they aren’t suffocated by excess water.

Should you Water Basil Every Day?

Before watering your Basil plant, check the soil. If it’s dry at least 1 inch (2.5 cm) down, you should water the plant. If there is still moisture on top of the soil, wait another day before watering again.

What Other Issues Could Ruin My Basil Plant?

White leaves are not the only problem that you will encounter. Gardening always presents new surprises, so even though this covers most of the likely challenges, sometimes there are further issues that sprout up.  

Basil Plant Troubleshooting

Can Pests Ruin a Basil Plant?

Japanese beetles, slugs and aphids, spider mites, caterpillars, and thrips are the most common Basil plant pests. These pests will not discolor your leaves but will leave holes in them.

If you can see these pests on your plants (usually on the bottom of leaves), you can spray water onto them to get rid of them. If you can’t see them, then use pest spray to get rid of them.

Did I put my Basil Plants too close to each other?

Farmer hands getting basil
If your Basil plants are grown too close together, their growth will suffer, or they may even die off before they mature into full-size plants. 

Competition between plants means they will struggle for light, space, and nutrients and interfere with the root health of one another.

Make sure to space your plants correctly. Since Basil grows best in full sun, we recommend growing 8 to 16 inches (20 – 40 cm) apart depending on how much sunlight is available where you live.

Do I Have the Right Drainage Strategy for my Basil Plant?

The problem might be that you are overwatering or under-watering your Basil plant. And what do you think is the most common reason for this? It’s probably because of inadequate drainage!

As mentioned above, if there’s too much water in the pot, it will create issues for your Basil plant. It can cause fungus or mold to grow on your potting soil and kill off your Basil plant roots. Overwatering and poor drainage tend to go hand in hand.  

So how do we fix this problem? Ensure there are drainage holes in the bottom of the pot. This way, water can drain out quickly instead of staying in the pot and rotting roots. 

You should also line the bottom of the pot with gravel so that any excess water easily flows through the drainage holes. The gravel size should be at least 2 inches deep- the more gravel there is, the better!

Even Basil Plants have Trouble Escaping Weeds

If you decide to grow your Basil plant outdoors, you will likely have to deal with the common menace of every plant grower.  Weeds are a pesky problem for any gardener, and they can be especially problematic for Basil. Basil plants grow very quickly, and weeds can outcompete Basil for nutrients and water in the soil.

Make sure to mulch around your Basil plants, which will help keep the weeds from growing and stealing nutrients from the roots of your Basil plant.

Summary

If you’ve read this far, you’re probably committed to maintaining your Basil plant. If your Basil leaves are turning white, it is most likely caused by nutrient deficiencies like nitrogen, fungus, excessive direct sunlight, or overwatering.

Growing Basil plants successfully takes practice. To fix the lack of nitrogen in your plant’s soil, you can add compost or manure. If you notice fungus on your plant’s leaves, it’s best to try an antifungal spray.

Basil plants do well in direct sunlight but in small doses, be sure to limit the amount so the leaves don’t yellow or wilt. Ensure you have your Basil plant in a pot with drainage holes to avoid excess water and moisture build up.

If these four issues are taken care of, your Basil plant should return to its healthy green self in no time!