5 Common Causes of Holes in Basil Leaves

03.05.2024 - 14:17 / gardenerspath.com / Kristine Lofgren

5 Common Causes of Holes in Basil Leaves

Whole leaves sprinkled on top of pho or mozzarella cheese. Mashed with pine nuts in a mortar and pestle into a rich pesto.

Layered on bruschetta, muddled into a mojito, or mixed into a blueberry cheesecake. Basil is the best.

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Sadly, many pests agree. There are a handful of invertebrates that will feed on basil leaves, rendering them full of holes. In addition, there’s a fungus that can also cause holes in the foliage.

Not only are these holes ugly, but depending on what’s causing them, the basil plant can even die.

We’re going to go over five causes of holes in basil leaves and what you can do about them. Here’s the list:

Pests are the problem most of the time, but there is one fungus that can cause holes in basil foliage. Let’s chat about that, first.

Cercospora leaf spot is an issue caused by fungi in the Cercospora genus. It causes dark spots on the foliage that develop tan centers as the disease progresses.

As the spots age, sometimes the tan middle will fall out, leaving holes with dark margins. The symptoms usually start on older leaves first.

In older plants, you just pluck off the symptomatic foliage and dispose of it. In seedlings, this disease can kill your basil entirely.

The fungus spreads through water, in temperatures between 77 and 95°F and high humidity.

You can work towards creating the right conditions by watering at the soil level and not on the leaves, and providing adequate spacing between plants. Check out our guide to growing basil if you need a refresher.

If the worst happens and your basil is infected, it’s copper to