I read Maurice's posts with interest. When I first started, what I heard was that JERSEY SPIDER was the only reliable rebloomed in Zone 4. It certainly is reliable - it has rebloomed every single year. However, 2014 was a long summer for us, with a lot more heat and sun than usual, and I had tons of plants rebloom. I do give nitrogen early, then in June organic chicken manure fertilizer, and I try to do a liquid kelp foliar spray (for minerals) two or three times a season. I'm also blessed with an inexhaustible well, so can leave the tower sprinkler on all night any time it gets hot and dry. So it does seem that, with these culture benefits and a long enough season, many many plants can rebloom even way up here. I have to say, though, that besides JERSEY SPIDER, the most outstanding dip rebloomer that year was ORANGE VELVET. It bloomed once in August, then a full rebloom - with five fully budded scapes, in October. Here is a picture of a scape taken on November 8, 2014 - still buds! That just NEVER happens here. So it was an usually long growing season, and these things seem to affect rebloom more than anything. This year was not as hot or sunny and there was nowhere near as much. 2014 was really a banner year.
