Nikki Ortega answer is correct
Oct thru Feb are the best months. However October tends to be warm until the very end sometimes until Thanksgiving. Butterflies will show up during the cooler monthes. Remember the caterpillar comes first & if its too hot they sort of cook in their cocoons. So the more mild years weather here are best. Also the more Eucalyptus trees or trees in general the better. Personally I lean toward February. Sadly, they have been disappearing over the past several years for some reason I dont know. However when the butterflies do finally show up, they are seen all over our area for miles.
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