Have you noticed brownish discoloured spots on your plant’s leaves? It might be downy mildew. Learn in this article how to identify it, treat it, and prevent it from happening!

What is downy mildew?

Downy Mildew is a fungus that mainly spreads to vines, tomatoes, and potatoes. Downy mildew loves humidity and warm weather, and because of its climate preferences, it is present all summer long. It spreads quickly as it develops on plants with dense foliage (that traps humidity and doesn’t let the sun come through). Although it first detectable on leaves, this fungus also spreads to the stems and fruit.

How to recognise downy mildew?

This fungus is easy to see, it translates into brownish-yellow spots on the top of the leaf that end up covering the entire leaf.  Sometimes you will also notice a white layer on the other side of the leaf. The fungus doesn’t stay on the leaves, therefore there may also be brown spots on the stems.

How to treat downy mildew?

As soon as you notice that your plant is infected by this fungus, cut off the affected area immediately to avoid it from spreading to the rest of the plant.

Once you cut off the infected areas, use the preventive methods to make sure it doesn’t spread to a different area of the plant:

  • A homemade solution that works well is baking soda. Mix 1 tablespoon of baking soda with 1 litre of water and spray it onto the leaves.  
  • A great preventative pre-treatment such as Phostrogen® Organic Fungus Plant Defence, which creates a natural barrier on the plant, and protects ahead of infestation.

How to prevent downy mildew?

  • As this fungus spreads quickly and is quite detrimental to the plant, it is important to consider these preventive methods all year round.
  •  As this fungus likes humidity, make sure to this out the foliage so that humidity doesn’t stay and to make sure all the leaves get enough sunlight.
  •  Make sure you leave sufficient space between 2 plants ad fungi are known to travel easily from one plant to another.
  • When you are watering the plant make sure you keep the water at the foot of the plant, don’t water the leaves as that will create humidity.