Chemical vapor deposition is a single-step processing method for forming functional polymer films on unconventional substrates, such as commodity textiles and living plants, and allows fabrication of rugged and sensitive fabric-, fiber- and/or plant-based sensors for wearable electronics and smart farms. I will the detail the materials science and engineering advances made by my team during the process of assembling various garment-integrated sensor systems and plant-based sensors for longitudinal health monitoring in native environments. In particular, I will highlight our recent work in developing garments for portable brain activity monitoring and activity tracking, and systems for in-home sleep monitoring.