Major depressive disorder (MDD) represents a complex psychiatric disorder characterized by the interplay of psychological, neurobiological, and inflammatory factors. Cognitive behavioral therapy (CBT) is recognized as the primary non-pharmacological intervention; nevertheless, a significant number of individual’s experience either partial or delayed therapeutic outcomes, thereby underscoring the necessity for safe adjunctive approaches. Lavandula angustifolia (lavender) and Echium amoenum have been identified as promising phytotherapeutic options exhibiting antidepressant and anxiolytic effects, bolstered by an expanding body of both preclinical and clinical research. This review aims to synthesize contemporary insights regarding the potential efficacy of these herbal remedies as adjuncts to CBT in the context of MDD, emphasizing the relevant molecular and neurobiological pathways involved. Both L. angustifolia and E. amoenum have been shown to influence monoaminergic neurotransmission, specifically the serotonergic, dopaminergic, and noradrenergic systems, which are pivotal to the regulation of mood and cognitive function. These botanical species demonstrate neurotrophic properties through the enhancement of brain-derived neurotrophic factor levels and associated signaling pathways, thus facilitating synaptic plasticity and neurogenesis. Their anti-inflammatory and antioxidant properties, achieved by the inhibition of pro-inflammatory cytokines and oxidative stress. In summary, the incorporation of L. angustifolia and E. amoenum into CBT signifies an innovative, multimodal strategy that resonates with individualized and preventive mental health paradigms, necessitating further exploration into the underlying mechanisms and clinical implications.