I think it's a Deutzia. Here is a link that might be useful:

Last night I changed all of my sprinkler heads to Hunter MP Rotators, the system ran at all zones, plenty of pressure. This morning my first cycle started, about 55 pounds system pressure, the heads in several zones would not pop, they raised about an inch and puked water, no spray pattern, and system pressure dropped to about 20 pounds during the tries. When I shut the zone off at the controller, system pressure jumped back to 50 - 55 psi. Yesterday I closed all heads off and activated the zones, one at a time, pressure remained high, around 50 psi, never changed, and no leaks came to the surface. By bypass valve I assume you mean the bleeder screw? There is no bypass on these valves, just the solenoid and a bleeder screw. I'll disassemble the valves this afternoon to see if there are any stoppages or debris. After that, I'm at a total loss! Thanks for the reply lehua.

I see you are in zone 2/3. Would this be difficult to grown in zone 8, hot humid south? Did you grow these from seed? If you think they will grown down here, I may just have to give them a try. Very pretty. Regina

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