I am not sure if I posted on your question about Downy Mildew, but Mancozeb/Manzate will NOT handle this problem. I took advice from a CR and professor of horticulture and ordered the Aliette (overnight, with the extra expense). I lost 2 roses but saved the rest of the bed. This is nothing like Powdery Mildew although many posters here have confused them. This is a potential killer.

You need to understand that hardiness concerns are different for bush roses such as hybrid teas as opposed to climbers. If bush roses are damaged all the way to the ground, they will still bloom in flushes through the season on new shoots from underground. If you plant with the graft or bud union (if any) below grade, they will do OK in midwestern zone 5b (not necessarily northeastern zone 5b). However, plants will stay small, maybe regrowing to 40" by fall. Do try Earth Song, it is more hardy, vigorous and disease resistant than any hybrid tea, and the flowers are similar, if slightly less glamorous. On the other hand, if climbers are severely damaged, the regrowth is mostly canes with few flowers. Climbers need to be cane-hardy every year in your climate, and most are NOT cane-hardy in zone 5b. Local advice would be good, or tell us where you live. Aloha, for example, has been cane hardy in southern Michigan. Alchymist should be good. Quadra and Ramblin' Red are often recommended for zone 5.

Sounds like whitefly, a very common hibiscus pest. The miracle chemical to get rid of whiteflies is a systemic called imidacloprid. You can buy it in Bayer Rose and Flower spray or Bayer Tree and Shrub drench. The spray is good for smaller plants, the drench for larger shrub sized plants. Both of these are only labelled for outdoor use, however, and I can't spray outdoors in the winter, obviously. I used to wait until a relatively warm day, drag the plants down a flight of stairs to the garage, line the floor with newspapers, spray and let them dry, then drag them back upstairs. A real nuisance and rarely would we get a suitably warm day when I needed one. The drench lasts for a year, so theoretically you could treat outdoors in the summer and be good for a year, but that won't help you NOW. I finally bought a jug of marathon granules, which also contain the same chemical. Unfortunately, the granules are geared towards commercial growers and the smallest size I could find was a jug of 4 or 5 pounds, which costs around $130! I have a lot of plants, so I'll use it up eventually. We also use the granules in my job taking care of office plants - they work very well on fungus gnats, scale, mealybugs, thrips, pretty much any sucking insect EXCEPT spider mites, and we don't have to worry about spraying inside the offices. Your best bet now would be to spray thoroughly with a horticultural oil, repeat every week for several weeks, and hope that does the trick until you can get the plant outside to use some form of the imidacloprid on it. (I see that you are in Canada - I hope the stuff is available there!) My first winter with a lot of hibiscus I had spider mites and root rot. The second year I had horrid whiteflies. The third year I used the granues in March (that was March of 2006) and also used a horticultural oil for quick knockdown (the systemic takes a while to work its way into the plant, especially the woodier ones). I have not seen any whiteflies indoors since March of 2006 and I haven't re-treated yet. Some people claim that using imidacloprid can make plants more susceptible to spider mites, but I haven't found that in my experience. Good luck, and let me know how things work out!

I will assume you are referring to bearded irises. If not, ignore the following advice. Try removing the potting soil and replacing it with a lighter mix, mixing lots of perlite into the potting soil to create a sort of "dirty perlite". Then be very sparing with the water, allowing your irises to dry out between waterings. If you're getting fungus or mold, you're overwatering. Overwatering potted irises can easily lead to bacterial soft rot infections. Don't fertilize potted irises over winter. This is supposed to be their dormant period, so it is counterproductive to promote growth right now. Place them in your sunniest window or under lights. Even so, the foliage will grow weak and floppy until the irises get back in the ground next year. The weak foliage won't hurt the plants; it'll just look messy. Watch your potted irises for aphid infestations. I always have problems with aphids on irises I overwinter indoors. If you squish them daily, you can keep aphid populations in check. Laurie