The combination of both effects enables manipulating the relative stability of lying and standing polymorphs substantially: In detail, we predict that the phase boundary between lying and standing polymorphs can be shifted in a temperature range of about 100 K when applying electric fields between -3 V nm -1 and +3 V nm -1 in a pressure range that is experimentally relevant (1 × 10 -12 to 1 × 10 -3 mbar). A permanent dipole is not required to use external electric fields to impact the polymorphism if the dipoles created during adsorption are sufficiently distinct. However, how strong the effect of an electric field is, of course, depends on the investigated system. This is because effects other than the anisotropy of the polarizability, e.g., the nature of the bond to a (possibly partially passive) substrate, can play an additional role. Regardless, introducing electric fields as an additional lever in deposition experiments opens doors to conduct growth in technically less challenging temperature and pressure regions or even to stabilize polymorphs at hitherto inaccessible regions.