Scott, I've just been treating pear blister mite for the last three years. I had it before that, but it took me some time to figure out what was causing the blistered leaves. After I learned it was blister mite, I sprayed pears with oil in the fall and spring for a couple years. Last year I sprayed just in the spring (according to my records it was on 3/24). I tried to follow Cornell's recs at first. They recommend a fall and spring app. As I mentioned, last year I just sprayed in the spring (with oil) and saw no evidence of blister mite. This year I totally forgot about it and didn't remember to spray until the first week in April. Still at that point there was little (if any) green tissue showing on pears, so I think I was still in the window. To date, the pears have all leafed out and I don't see any signs of blister mite. Cornell recommends a fall spray in early Oct. followed by another oil app. in spring just before green tissue begins to show. I'm sure you're aware the mite has a somewhat complex life cycle. In the fall, they move into the bud scales (mostly preferring flower buds) and overwinter (The idea for the fall oil spray is to nail them before they move into the bud scales.) In very early spring, they move out of the bud scales (this is the second opportunity to nail them) but females start laying eggs in green tissue once it starts to emerge. The new colonies are protected from insecticides inside the blistered leaves. So in that sense, pear blister mite is like peach leaf curl, once damage is visible, it's too late to treat.

Fall-Winter is my favorite time to garden! The hot weather here in the Central Valley, California, makes me very sick (heat/sun stroke, losing my pigments, sunburned very easily). I measured the temperature in my garden this morning about 6:40 a.m., between 27-31 Degrees F. Our roommate's car at 7:15 a.m. still has solid ice all over the entire car! I'm amazed that all of my Tomato plants (Pear and Cherry) are still looking healthy, with no signs of stress. My Tomato plants have always died before when the temperature drops below freezing. Maybe they are acclimatizing to the cold weather ..... Looks like all of my seedlings are enduring this chilling weather. I have over 100 different kinds of plants growing now, including summer plants: Tomatoes, Eggplants > Thai, Peppers, Basil, Zinnias, California Poppies, Morning Glories, Four O'clocks, and more ... Now, if only the gophers will leave me something to eat this Winter .... Stray cat's nearly destroyed my most recent seed bed. Picked fresh Southern Curled Mustard and Red Giant Mustard and Chinese Cabbage to add to my sandwich yesterday! Looking forward to fresh Lettuce, Beet Greens, Collard Greens, Kale, Kohlrabi Greens, Swiss Chard, Radish Greens, Stinging Nettle, Dandelions which should be ready soon ..... -- Jim (Central Valley, California) > Climate Zone #8/14 > Hardiness Zones #8-9a

Heart breaking pictures. Sorry. BUT, as you know, this is simply a fact of life in the world's most continental climate. (in the sense of ridiculous swings. While Siberia and Northern China are cold as can be in winter, they stay cold, and when spring arrives, it arrives for good) I've assumed the facilities that have to contend with it either use sprinklers or tyvek-like row cover/blankets to protect rare plants. We can just get so darn warm in winter. Resin and I had a chat a while ago about where to collect the Cornus florida that would do the best in the UK. He brought up the issue of northernmost collections being used to a winter that stays winter...but even that's not true. Syracuse NY is probably its northernmost range in the interior of the east coast, and even it can get warmer in February than London. Yes, only by a degree celcius, but you're talking about a zn 5 with 100+ inches of snow versus a zone 9 with many subtropical plants like Eucs being quite common. Of course a C. f. from Asheville might still be a better collection for the UK, but the notion even our northlands always stay cold is a false one. Related to the reason I came here today, apparently the guy who had the largest collection of magnolia hybrids in the SE lost a huge number of them back in 2006 or 2007 when a freeze in SC/NC brought temps to the teens in April after they were fully leafed out. 30' Gresham magnolias died totally...not even able to sprout again from the base. They have the Chinese & Himalayan genes that are used to the far more consistent winters there. This post was edited by davidrt28 on Tue, Feb 26, 13 at 14:28

Well I just checked my containers, well I got good news and bad news. Bad news that lupine that had germinated before the freeze is not going to make it, though now I have another new sprout so I will cross my fingers it may get a cotlydon before another freeze moves in. Also lupine does not reseed in my area, it does not even grow in my area and yes this is the perennial that needed a cold period. Good news pretty much everything else looks great, I found some new sprouts also. Now my soapwort, mexican tea, bronze fennel, rosemary and a dianthus has now germinated. So for what I think no matter if it is perennial annual herb veggie if it reseeds you can winter sow it with no extra protection after germination even if a freeze moves in. If doesn't reseed you may lose it after a freeze that happens after germination!!