That will be March 2011, here are details, 'Enter the Secret Garden" (don't you love it):
http://www.ballaratbegoniafestival.com/
I hope it does not coincide with the Altona Bayside Festival, which is also held each March:
http://altonabeauty.blogspot.com/2010/07/attraction-15-altona-bayside-festival.html
I will like to take some photos of the Festival and write an article.
You've just missed the Golden Wattle Festival in Maryborough, but the Goldpanning championships are coming up, then there is Lavandula Lavender Farm, very, very beautiful:
http://www.lavandula.com.au/
It's just up from Daylesford. Incredibly beautiful.
I have not been to Maryborough but agree with you that the Lavandula Lavender Farm is indeed very beautiful. Like the lunch at the La Trattoria too!
Been there twice:
http://www.flickr.com/photos/anthony-linda/sets/72157608107226487/detail/
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