I just spawned out three dubtubs. In each, I had intended to retain a portion of the substrate to spread thinly over the surface after loading and leveling the spawn/sub mixture but on the first one I spaced out and forgot to save that portion so now the spawn/sub mixture is the surface and wheat grains are exposed.
Ordinarily I would just sterilize a little coir or verm and put it on top, but this is a comparative grow to test yield and potency from different substrates, so I cant add anything. Even verm could effect yield by altering pinset, I assume, so I'm hoping to avoid that.
Will having exposed grains increase risk of contam? And if so, will that risk drop off once its fully colonized and ready to fruit, or will it also pose a risk to the later flushes?