Pumpkins are suffering from a nasty case of mildew, so are the courgettes.

Holyhocks have had rust and the roses black spot.

So, am I just a terrible gardener or is there something about gardening in Eastern Ontario (or elsewhere in Canada) that I should know?

And any tips on getting rid of mildew on the veggies - seen a bunch of stuff on the interweb but interested to see if anything works well locally...

Yep, been having problems with me zucchinigettes too. Some rot from the flower down, some are ok. No other squash yet.

Hollyhocks are sad looking but the roses are ok

It's a damp year and have been told the zucchini thing is blossom end drop due to lack of pollination, so you need to get out there with a feather and cross pollinate. All I have done is to try and keep the fruit off the ground and let the air get to them by moving the leaves.

we are in coastal Nova Scotia (south shore) and have had all kinds of diseases in our plants this summer.
Apple trees are full of bugs, the mallows are rusty, beans have weird grey spots and our first crop of potatoes had all the leaves dying early, so we had to dig them up prematurely to prevent it from spreading into the rest.

Contrary to the rest of Eastern Canada, we haven't had a lot of rain in our particular area, but mildew has occured nevertheless in our hanging baskets.

sorry I can't help with any tips of how to prevent this, we don't use any poison to spray and just let nature take its course

A pretty good enviromentaly freindly method of control is to spray the leaves with a 10% solution of milk covering the upper and under surfaces. Most chemicals I have tried work but you need to repeat applications on a bi weekly basis.

Dithane 945 is the best spray if you can get it, spray every 2 weeks but hold off for the harvest.

Sprayed the milk/water solution last night. Now have lots of happy flies sitting on the pumpkin leaves. Maybe I overdid the milk...

Good luck with that, dont forget to retreat in 2 weeks or after heavy rain!