It looks like Ohio is setting up for another hot summer similar to last year. I need some guidance on what to spray or drench in the propagation bench to hold cuttings down especially Snow cap. I have been using cycocel with pretty good success up until last year when we experienced higher temps then usual.

A combinatio of B-Nine/Cycocel may be more effective for you, especially on a vigorous cultivar like Snowcap. We suggest 1000-1500 ppm B-Nine combined with 1000 ppm Cycocel applied as a spray which can begin in week 2 of propagation. Medium vigor varieties may only need 1-2 applications applied at 7 day intervals but Snowcap will probably need more like 2-3.

I like to use the B-nine / Cycocel early in the season on finished material.
When using the B-nine more than one time in the propagation bench. Is there any build up of in the cutting ?

As long as you keep the rates low you shouldn't have to worry about over doing it with the B-Nine. The use of B-Nine as you know does need to be discontinued by flower initiation to avoid a delay in flowering and reduction in bract size. If you are worried about too much B-Nine if you are also using it in propagation you shouldn't have to worry, especially on a vigorous cultivar like Snowcap. B-Nine is not residual in the plant long enough to cause problems with flowering or excess reduction in growth when it’s applied in propagation and well before flower initiation.