6 inch minimum. Small but viable
Willamette was originally Golding that was taken to the US. It was the predominant hops grown in the Willamette valley for almost 50 years. Very closely related to Golding but with a bit less florals and a bit more fruit. Absolutely lovely for English ales and American pale ales. Also good in IPAs used late!
US testing has put it at 6.5%AA with 23% Cohumulone
Probably the closest hops to Amarillo thats available to the Australian growers.