Powdery mildew is a common issue for zinnia growers, especially in the initial days of planting.

While there are popular ways to combat the issue, most of them require the use of store-bought fungicides that are full of harmful chemicals. Even though the fungicides do work pretty well, they can often end up harming the annual in the long run.

In today’s article, let’s go over some legit ways to treat powdery mildew on zinnias without the use of chemicals. Like always, all these solutions are tried and tested beforehand to ensure a good mix of anecdotal and theoretical evidence.

Zinnia with Powdery Mildew

If you’re unsure of what to look for when trying to spot powdery mildew, some quick visual cues can help.

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You’re looking for some sort of unusual white or greyish powder that may be coating the flowers and plant foliage.

Oftentimes, this powder goes unnoticed because it’s on the backside of leaves, so make sure to flip every single leaf over and inspect carefully.

Catching mildew early is key. And if you’re aiming for the fullest blooms possible, these simple tips can help you maximize flowering on your zinnias.

Zinnia flower

While powdery mildew is a fungal infection, it rarely kills plants. More often than not, you’ll find the powder to be purely cosmetic, but that doesn’t mean it’s not causing harm behind the scenes.

Powdery mildew can actually weaken the blooming potential of your zinnias and cause them to take on a paler, more dull appearance. Early spotting of this fungal disease ensures long-term health and blooming of your zinnias.

And if your zinnias are looking a bit dull, it might not just be disease, here’s how to feed them properly for stronger growth and vibrant color.

watering zinnias

  • Avoid getting the foliage wet when watering. A drip hose is ideal for watering this water-sensitive annual. 
  • Space your zinnia plants out at least 10-18 inches apart to lower any chances of overcrowding and airflow restriction. 
  • Mulching around the base of your zinnia plants can help with temperature regulation and moisture control. 
Zinnias

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