Semanggi (Marsilea crenata Presl.) is one of the aquatic plants that have been widely used by the community as food and medicinal raw materials. One of the important factors in cultivating clover is optimal fertilizer management. The incorporation of organic and inorganic nutrients has an effect on soil fertility has been repeatedly demonstrated in several studies, but there are not specific guidelines on clover cultivation. The challenge now is to combine organic matter of different qualities with inorganic fertilizers to optimize nutrient availability for the clover plant. The results of research on clover cultivation have also not been widely carried out. Therefore, it is very important to do this research with the aim of knowing the optimal effect of organic (cow manure) and inorganic (nitrogen, potassium) fertilizers on the growth and yield of clover (Marsilea crenata Presl.). The research was conducted at the Screen House of the Faculty of Agriculture, Brawijaya University. The study was designed using a non-factorial randomized block design (RBD) with 8 (eight) treatment combinations of soil types and fertilization [inorganic (N, K) cow manure organic fertilizer (CM)], namely: P0 = soil, without fertilizer; P1 = soil, 138 kg N ha-1; P2 = soil, 136 kg K ha-1; P3 = soil, N and K, 138 and 136 kg ha-1; P4 = soil, 20x103kg of cow manure ha-1; P5 = soil, 20x103 kg of cow manure ha-1, 138 kg N ha-1; P6 = soil, 20x103 kg of cow manure ha-1, 136 kg K ha-1; P7 = soil, 20x103 kg of cow manure ha-1, N and K, 138 and 136 kg ha-1 with 3 replications, so that 24 experimental units were obtained. Each experimental unit consisted of 5 plants. Growth observations were observed destructively at the ages of 4, 8, 12, 16, 20, 24, 28, 32 days after planting (DAP). The results showed that there was an increase in the growth and yield of biomass in the soil combination, 20x103 kg of cow manure ha-1 (P4) was compared with the treatment without the addition of organic fertilizers (cow manure) on plant growth and yield parameters, such as stolon length (74.78 cm), number of leaves (160.44), leaf area (1379.28 cm2), root length (23.85 cm), stomata density and number of stomata (13.25); Stomata width (10.87 cm); Stomata length (19.76 cm), leaf fresh weight (12,907 g), leaf dry weight (1,802 g), total fresh weight 210,830 g, total dry weight 7,823 g, leaf harvest fresh weight (64.19 g); stalk (130.54 g); root (79.75 g); total 274.48 g), harvest dry weight of leaves (11.36 g); stalk (24.88 g); root (9.55 g); a total of 45.78 g) and the chlorophyll a content (0.804 mg.g-1); chlorophyll b (1.121mg.g-1); and total chlorophyll (1.924 mg.g-1).