© 2020 American Physical Society. Single crystals of solid solutions of ferromagnetic superconductors UCoGe and URhGe were investigated by magnetization and specific-heat measurements. These compounds behave as anisotropic ferromagnets with the easy-magnetization direction along the orthorhombic c axis. The maximum Curie temperature TC=20K has been observed in UCo1-xRhxGe for x=0.4. The main interest of the study was the intriguing behavior in magnetic fields applied along the b axis. The temperature dependence of the b-axis magnetic susceptibility exhibits a maximum at a characteristic temperature Tmax. For low Rh concentrations (x<0.4)Tmax>TC and the magnetic entropy Smag at TC is very low, whereas Tmax=TC and the Smag at TC is much higher for x≥0.4. A metamagneticlike anomaly in magnetization is observed in all compounds, at a critical field which appears on a similar energy scale with the value of the corresponding Tmax. The character of three paramagnetic regimes which can be distinguished in the T-x and H-x phase diagrams, normal, correlated, and field polarized, is discussed in relation to the field-induced reentrant superconductivity in the parent compounds.