Virginia fanpetals (Sida hermaphrodita) as a crop plant is characterized by high biomass yield, high protein content and good fibre composition. The aim of the study was to evaluate ruminal degradability of Virginia fanpetals herbage and silage of first swath and regrowth. In situ ruminal degradability was determined using 2 rumen fistulated heifers fed standard diet. Degradation was estimated using nylon bags with dried feed placed in the rumen for 2, 4, 8, 16, 24, 48 and 72 h. Ensiling accelerated the dry matter (DM) degradability of first swath in the first hours of incubation and slowed down in the following hours. Ensiling the regrowth accelerated DM degradability both in the initial and final hours. In the silage from regrowth effective rumen degradability (ERD) of DM and neutral detergent fibre (NDF) were higher than in herbage. Ensiling accelerated crude protein (CP) degradability in both swaths so ERD of CP was higher in both silages. The results of the present study show that Virginia fanpetals green fodder preserved by ensiling can be successfully used as supplementary forage for ruminants. In particular, first swath silage, due to its high protein content, can be used instead of legume silage in diets for cattle, and also it can reduce the need to use high-protein concentrate. However, ensiling caused significant acceleration of rumen protein degradability, which with unchanged DM and fibre degradability rate is not a desirable effect and requires simultaneous delivery of easily digestible carbohydrates into diets.