Belgian yeast strains.

I'm planning on brewing a Belgian golden ale and was thinking of combining wlp500 (Trappist) with wlp568 (Saison blend). I planned on starting fermentation around 68 and letting it ramp up naturally. I'm wondering if there is any way to tell which yeast would be dominant in terms of flavor profile?

No way to really tell, but my guess would be that because the wlp500 is a slow starter, at the other yeast would get going first and contribute more flavor.

I have been working on a Tripel recipe using 2 yeasts. I used 1214 and 3787. The first time I brewed it the 3787 flavor was more pronounced. I think that the first yeast to take off is the one that contributes the most flavor. The second time I brewed it I did a starter of the 1214 and pitched it at high krausen and just added a pack of 3787. This batch has more 1214 flavor but the 3787 does come through.

It is fun to experiment.

Interesting. I may go the route of starting with the wlp500 and adding the Saison yeast later in the fermentation then. Maybe ferment the wort with wlp500, rack the beer, then add the candi sugar and referment with the Saison yeast.

If you want one to be more dominant, you could always grow a starter of it before pitching, in an attempt to control the ratio of yeast (by strain) pitched.