Biopolymers are novel materials that are slowly gaining momentum in ground improvement, especially for ameliorating cohesive soils. However, their biodegradability and reduced stiffness under soaked conditions have led to a significant reduction in resistance. Crosslinking of biopolymers has been reported to overcome this limitation of biopolymers. The current study investigated the influence of crosslinked biopolymer made at different concentrations of chitosan and gellan gum for enhancing the wetting and drying (w-d) and California bearing ratio (CBR) behavior of silty clay. The curing period was varied from 7 to 28 days considering the practical applicability. The highest unconfined compressive strength (UCS) measured before the onset of the first w-d cycle was reported as 2.75, 3.0, 3.5, and 3.9 MPa after 7, 14, 21, and 28 days of curing for sample treated with 75% chitosan and 25% gellan gum. At the highest curing period of 28 days, the formation of a three-dimensional fibrous network increased the stiffness and reduced mass loss of soil-biopolymer mixes prepared at 75% chitosan and 25% gellan gum and sustained up to 10 w-d cycles. The scanning electron microscopic images of the samples revealed the presence of soil aggregations linked by biopolymer fibers. Additionally, the soaked CBR at chitosan content of 50% and 75% satisfied the minimum CBR criteria of 5% as per IRC 37. The key findings established the potential of utilizing crosslinked biopolymers to enhance the resistance of cohesive soils against harsh weather conditions and thus can be suitably used as subgrade material.