Yes you can primary with Lambic blend. Lambic breweries spontaneously ferment, so nothing is added to a secondary. Be aware that the blend is a crazy active fermentor and you will need a blow-off. Once it's finished primary you can leave it, but also be aware that with all the blow-off you will have quite a bit of head space and may want to carefully transfer to a secondary to avoid excess oxygen permeation over the long time it takes to make a good lambic. A pellicle will help protect the beer if not transferred, but once the effects of oxygen set in it ruins a batch.