I guess what I am wondering is if the reason why people are now wanting to spray oil later is that everyone is using light oils and they don't work very well in full dormant periods. So, maybe the heavy oils actually would work well in full dormant, just as well or better as a lighter oil later. I looked around for studies of different kinds of oil compared and could not find anything (well I found one paper stating that heavier oils are more effective but just that sentence). There still is at least one heavier dormant-only oil being sold that is made by PBI Gordon. Hey I just found an interesting old study, see below. It states that heavier oils work better, but it also points out that the rosy apple aphid wakes up later and that is the biggest aphid problem for apples showing the importance of a later spray. On apples the rosy apple aphid is about the only reason why I spray oil so it sounds like I should aim my oil spray at them only, and do the later spray with lighter oil. Harvestman, this may be the reason why you prefer the later spray. This study suggest lime-sulphur later because the light hort oils did not exist when it was written. Overall, it sounds like for scale a heavier oil is better at delayed dormant, and for aphids a light hort oil later is better. Scott Here is a link that might be useful: study

Every brand will be different. You really need to follow the label directions of the one you are using. In the past, the ones I've used have had different concentrations for different crops at different seasons. There would be one concentration for fully dormant roses, and a different one for roses during the growing season. More is not better. If the concentration given on the label doesn't work, then you need to try something different, not a stronger concentration of the same thing. Lime sulfur is not a cure-all and using more of it wont' make it work on things it doesn't work on. Too high a concentration can cause damage, to your plants, to your soil, to yourself. What is it you're trying to fix by spraying with lime sulfur? Are you mixing it with dormant oil?

Lime sulfur can be sprayed at any time of year (except when trees are in flower to avoid harming pollinators). It is just a fungicide - and a natural one at that - and is used frequently to combat fruit tree ailments that can occur after leafout - like scab. One of the recommendations for treating scab is to spray just as the leaves are falling, as well as during the dormant period and again as the tree is leafing out or until the climate conditions for scab no longer exist. In my area, that was well into June this year :-) It is sulfur that can become phytotoxic to foliage. Adding lime to the mix reduces the phytotoxicity - the more lime, the less phytotoxic the mix. The lime itself has no antipathogenic effect. It is included only to neutralize the sulfur. Copper fungicides can also produce phytotoxic results. But using them at this time of year hardly creates any sort of serious threat of phytotoxicity. Any leaves treated with dormant spray (horticultural oil) and/or copper or lime sulfur fungicides - all of which are considered natural or "organic" controls - are harmless when included to compost in a moderate amount.

Go to weather underground, enter your zipcode, on the left side go down to weather history. The link below is to Buford Georgia. You'll see a choice of day, week, month, and year. Look the the yearly averages. (You may also have an option to copy last years temeperature history, which is really worth having.) What you need to know is when the historic warm spells happen and which are followed by serious cold. What you don't want to do (contrary to some comments above) is shock the roses into dormancy, only to have them hit by a January warm spell when new growth will happen, only to be killed by cold in February. Lime sulphuring now, will just kick the premature spring growth into the warm spell in early December, which is a total disaster. Try to understand what happens in your garden. In Jean's garden, in the heat island east of Nashville, her best use of LS is often the last two weeks of December. My garden is colder than hers by about 7 degrees + or -. My most effective uses of LS have been the first two weeks of January, which is often before buds begin to swell whether I want them to, or not. I look to LS to adding a couple of weeks of cold and maybe take the roses through the early Feb warm. This business of temperature swings happens every winter, sometimes I can hit with LS and get really good results. There have been winters that have been warmer and dormant strength LS just doesn't get applied those years. While I'm muttering: you can spray LS when it's below freezing. Just use hot water in the sprayer. The air makes sure that it doesn't hit the rose warm, but it keeps some of the sulfides in solution effectively. Here is a link that might be useful: Buford Georgia weather underground portal