Answered by Hum Zhou Wah from Canada | Apr. 14, 2013 14:24
May;
I think that what is in your heart is more important than any actual date. The traditional dates for observance are simply too cold here in Canada. This year, right now, gravestones are still buried under snow. So, my family has changed the dates to warmer dates, months after the traditional Chinese date of the first signs of Spring in China. Typically, we don't make the trip to the grave until after May 24, after the muddy mess of early Spring thaw, and after vegetation has had an opportunity to "come back to life".
That is to say, so long as you do set aside a somewhat regular date for annual observance and treat that day with appropriate reverence, then your duty to honour your ancestors`memory would be fulfilled, IMO.