I have not in the past few years but this year I'm thinking about it. My only concern is that I have praying mantis out there. If it will harm them, I change my mind.

Why-are we going to get a new ``Ice Age''?

A lot of people on the forum swear by it, and so this spring, if it proves to be fairly benign, I will give it a try too.

Pete, it sure feels like an Ice Age has arrived around here today.....

Judith

Ice Age here today too. It is UGLY outside. I miss Pete.

Dormant oil spray and lime-sulfur dormant spray.
Yes, indeed.

In a pinch, if we can't find lime-sulfur dormant spray, just a good heavy dormant oil spray.
Goes a long way toward suppressing various pests and diseases.

Jeri

I didn't the past two years because I was vigilant about my regular spraying. But last winter and this fall I have a lot of blackspot. We had a warm spell last week and I spray with my regular spray (Bayer) because many of my roses still have leaves and some had new growth.

It's going to get colder after today (when it rains! Yeah!) so at least the leaves that drop will not carry bs with them.

I plan on doing the lime sulfur spray on the canes and I usually also spray the mulch surrounding the roses (because that's where the spores harbor). Last spring my roses had bs as soon as they leafed out because our winter was so mild, it over wintered on them. I don't want that to happen this year.

The only down side is the sulfur smell.

Is the lime sulfur something you buy or mix up yourself? What would a heavy dormant oil spray intail? Do you wait until very late in the Winter season to spray them?

Red, lime-sulfur dormant sprays and dormant oil sprays are availble in most good garden centers here.
You can actually use any good horticultural oil for the purpose -- just mix it at the strength recommended
for dormant spray purposes.
Sunspray oil, Neem Oil, ANY horticultural oil will do.

We apply them after whatever pruning we do. Sometimes, with roses to big to defoliate, we spray them and
wait for a good East wind to get rid of the killed leaves. On our hillside, that works well.

Jeri

So what about my mantis's? They are probably laying eggs. Will dormant spray kill them?
Mary

Sorry Mary. Don't know.
I would probably recommend that you avoid spraying the eggs, as the oil certainly does smother the eggs of less-desirable insects.
Usually, dormant-spraying is done AFTER pruning, so at that point, you are spraying a nekkid plant. Would there be mantis eggs on nekkid plants?

Jeri

Jeri, thanks. Duh, of course. I will hopefully find my big egg cases, glue them to a chopstick and set them in the nandinas where they will be safe. I am just not quite altogether today. Must be all those Christmas cards I have to work on today when I really want to be out puttering in the roses....LOL
Mary

Red, the classical dormant spray is a mixture of horticultural oil and lime sulfur. The lime sulfur is a fungicide, mostly, and the horticultural oil is mostly an insecticide although it will destroy fungus spores. Rose leaves are easily burned by lime sulfur/ oil mixtures and that's why their use is restricted to the dormant season. I don't know about your zone 6, but here in my zone 5, I don't see a lot of use for a dormant spray. The few insects that bother my roses (japanese beetles and aphids, mostly) do not spend the dormant season on my roses either as hibernating adults or as eggs. The only serious fungal disease in my garden is blackspot and several studies have indicated that blackspot spores: a) are not released during our winters, b) do not germinate at our winter temperatures and c) in the absence of germination, do not survive for more than a few weeks. This means that the only source of blackspot reinfection that's present in my garden near the end of the dormant season is the adult fungus, living either in infected fallen leaves or in infected lesions on the canes. Lime sulfur/oil sprays do appear to kill blackspot spores, by smothering or perhaps dehydrating them, but what's the point of that during the dormant season in a cold climate? I know of no evidence that lime sulfur/oil sprays do anything at all to the adult form of the blackspot fungus.

I spray Volck oil on my roses after pruning every year. I
am not sure if it helps, but I like the idea of a "fresh
start" every year. FWIW, I have plenty of praying mantis in
my yard even with the spraying, but even though they hang out
on the roses I rarely find any egg cases on them. As said
earlier, you are removing the foliage anyway, so no harm done
unless there are egg cases attached to your canes.

So I can mix the oil and the sulfur together and spray at the same time? Does anyone know what the ratio is?

I do. And it really seems to help. I mix the oil and lim sulfur together when I spray (seems to mix better in warm water. I always go with the directions on the label, in case some brands have a different ratio than others.

I also skip the winter spraying. In March, I will spray Daconil and maybe repeat in April. Come May, I will begin spraying Bayer and hopefully keep up my program.

I didn't use dormant spray last year, and regretted it. I had lots more rust and blackspot than usual even with fungicide spraying. I am in zone 8 and prune in late Feb. I spray lime/sulfer mixed with horticultural oil in the amounts called for on the container immediatly after pruning. This will burn any leaves that are left on, but new leaves will take their place as the roses start growing in the spring. I highly recommend it.
Kathy

Lime sulfur spray is harsh stuff and though I don't wear a mask or respirator when spraying regular fungicides, I do when spraying Lime sulfur. It is not good for your lungs. It also can stain.
Linda