3 Common Causes of White Spots on Lettuce
It can sometimes seem like lettuce and fungal issues go hand-in-hand.
Both these leafy greens and many nasty fungal pathogens love nothing more than moisture and cool temperatures.
If you’re seeing white spots on your lettuce, it’s usually a safe bet that a pathogen has infected your plants.
But it’s not just fungi that can cause white spots on lettuce leaves.
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There’s also a pest that strongly resembles a fungal disease and has fooled more than one experienced gardener into thinking that their crop had some sort of disease, when really it was an infestation.
If you need a refresher about how to grow lettuce, check out our guide.
In this article, we’ll help you narrow down the cause of white spots on your lettuce and figure out how to treat the problem so you can get back to enjoying your favorite salad.
Here’s the lineup:
If you’re seeing spots, you need to act sooner rather than later, so let’s dig right in and look at the three common issues that cause white spotting on lettuce crops.1. Downy Mildew
Downy mildew has pretty distinct symptoms.
This disease, caused by the water mold (oomycete) Bremia lactucae, appears as yellow or light green angular spots on the top surface of the leaves.
On the undersides, you’ll find blotches and spots of white fluff.
As the disease progresses, the upper lesions turn brown and dry, and if left unchecked, the leaves might die entirely.
It typically starts on the older leaves and rapidly spreads to new growth. If downy mildew takes hold at the seedling stage, the plant will likely die.
The pathogen attacks all species in the LactucaRead more on gardenerspath.com