Mildew on Sweet Peas

happycottontail

What’s the cause, and how can you prevent it or stop it in its tracks? I have been watering the plants every day through the heatwave 😒

lovegardening77

I googled it and RHS say to water round the base trying not to dampen the foliage.

Fairygirl

Pretty normal, even in a normal summer. I don't have many of mine in full sun either - and we don't have the prolonged heat that more southern areas have.
They're just dry, and watering once a  day in the kind of temps some areas have had isn't actually enough. Sweet peas need huge amounts of food and water to keep them going. They also need good air flow round them, so if there are too many planted closely together, that can have a  negative effect.
Bear in mind that a lot of watering can also eliminate food from the plants, so if you have to water a lot, you also have to replace their food, especially if they're in pots. 

Fire

Mine are certainly struggling this year. I'm watering and feeding a lot but they are sulky. Some mildew, no great display and almost no scent. It seems a shame with all the work that's gone into them since Easter. Ho hum.

Fairygirl

You win some - you lose some, Fire 
It probably hasn't been ideal for them this year in many areas.Mine are the same as usual, but we haven't had the longstandinghigh temps that you've had. 
I also think it's misleading when people are told to plant sweet peas in full sun. I think they do better with a bit of relief from full sun.

Mary370

Mine are doing fine this year, but they are in the ground.  Put some in pots last year, they were hard work and didn't do nearly as well as the ones planted in the ground.

Pete.8

I think it's the unusually hot weather we've had this year that is the root cause.
Peas, beans and lettuce all prefer cooler temperatures.
My sweet peas had bad mildew last year for the same reason. I've not grown them this year