Hi smdmt: The biggest cause of death in roses through the winter is not cold, but dryness. Mildew is the 1st sign of dryness. We have a dry fall, early winter in my zone 5a, Chicagoland.

I should had mulched the base of my roses weeks ago. My leaves haven't fallen off yet. I'm waiting for warmer temp. to dump soil, then rake leaves around roses. My bags of top soil are frozen.

I collect used kitchen-water when I wash veggies, and use that to water my roses, even during the winter. Seil in MI, with many roses, also water her roses during the winter. I have a few roses that survived last brutal winter, but died early spring ... we had a dry spring.

Another person in zone 4 stated that roses die in the winter NOT because of cold, but because of drying out. Leaves and mulch on top help to protect roots from drying out.

Strawberryhill, should I wait until the leaves naturally fall off or should I pull them off? Don't want the mildew hanging around.

Hi smdmt: I would prune roses down to 1 foot, and let the leaves fall off naturally. We have free-yard-waste disposal until end of Nov. But if I wait until spring to prune roses, there are disadvantages:

1) I have to pay money for yard-waste bag disposal.

2) My Firefighter hybrid tea WAS NOT pruned before winter, so it was tall & lanky and the wind broke the bush.

3) My neighbor pruned over a dozen hybrid teas down to a foot tall, then piled woodchips on top ... they all survived the winter and very bushy in spring.

4) It's easier to pile up alfalfa hay or leaves on top of pruned roses. It's safe to prune roses and winter-protect after the ground has frozen, or when the temps are in 20's.

Smdmt, regarding mildew: From my experience, mildew occurs when the soil is too acidic, plus too much salt from fertilizer. There are a few roses with mildew in my garden: either I put too much gypsum (calcium sulfate, with 17% sulfur and 8% salt), or acidic cracked corn (pH 4), or milorganite (high-salt sewage sludge). One time I induced mildew on Mary Magdalene rose by dumping acidic high-nitrogen chemical, thus high salt fertilizer. That occurred despite tons of watering. I learned my lesson.

The roses in my alkaline clay, pH 7.7, fertilized with zero-salt alfalfa hay have zero mildew. Same with roses which I dumped horse manure, aka mushroom compost, at pH over 8.

This post was edited by Strawberryhill on Mon, Nov 17, 14 at 14:06

I have to do things different here...

We can't pile anything around our canes because the canes would all canker from the wetness we get from our winter snows & rains... Been there done that...lol
(Now I'm talking about putting a material against or covering the canes) not material over top the root system and away from the canes...
Each of our gardens is different...
So I only will plant winter hardy roses that will survive zone 4-5 winters without any protection needed...
Winter winds dry out roses...

And we do not hard prune until early Spring...

If you want to after some hard freezes just pull the leaves off and clean the area up then its up to you whether you prune them down or not and/or apply protection...

This post was edited by jim1961 on Mon, Nov 17, 14 at 17:00