Powdery mildew on perennial sweetpeas
 

Hello,

I recently received perennial sweetpea plants in the mail, and as the instructions said they shouldn't be put out when temperatures are below 10C, I've potted them on and stuck them in the conservatory as I don't have a greenhouse. They're putting on lots of new growth, but they've also now got a lot of powdery mildew. Any ideas for getting rid of the mildew? Is there a spray that is human/pet-safe?

Thank you!

Mildew is often worse when the roots are dry. See if you can move them to somewhere cooler, pinch out the tops, possibly repot them, and don't let them dry out.