you can pick them when they're ready. typically they'll all be ready about the same time though. In the past my first years have put out 2 mini harvests (both combined weren't enough for a batch).
PrimaryLambic (WYeast blend), Local Lambic (spontaneous fermentation), Flanders Red with ECY02
SecondaryFlanders Red, Oud Bruin,
Bottled Burton Ale, Wet Hopped IPA, Roese Kriek, "Grimm" RIS 23%, Saison Du Flood,"Warrior" IIPA 17%, "Oaked Warrior" IIPA 17%
Kegged Little Bastard IPA 3.5%, Top Secret Barleywine aged on vanilla and oak