These are NOT recommended for use as foliar sprays.  Firstly, the calcium in Cal-Mag additives (and base nutrients) will cause white staining on the surface of foliage.  During daylight (lights-on), this can hinder photosynthesis and cause burning of foliage (aka “necrosis”).  Also, the nutrient species used in Cal-Mags or base nutrients are not ideally suited for uptake via stomata.  For maximum uptake and efficacy, it is best to use a specialized foliar spray such as FloraMax Clone Spray.  This can be used for seedlings and clones, then throughout veg and in early bloom through to about week 3 or 4 – but generally not later than this.  The ingredients in Clone Spray are designed for maximum uptake via stomata and will impart the necessary benefits desired from a foliar spray e.g. improved foliage growth, increased number and quality of bud sites, improved plant structure and increased root mass.