Budidaya krisan di daerah tropis seperti Indonesia, diperlukan pemberian cahaya tambahan. Penambahan cahaya dilakukan dengan pencahayaan buatan dari lampu listrik di malam hari selama 4 jam, setelah matahari terbenam. Penelitian ini bertujuan menentukan pola siklik terbaik untuk menghasilkan laju pertumbuhan tertinggi. Perlakuan yang diberikan dalam penelitian adalah penambahan cahaya lampu LED kombinasi warna merah-biru secara siklik (off, on, off). Jumlah siklik yang diberikan adalah 1 siklus, 2 siklus, 3 siklus, 4 siklus, 5 siklus dan kontrol. Data yang diperoleh analisis secara regresi. Variabel yang diamati adalah tinggi tanaman, jumlah daun, luas kanopi daun, dan diameter batang. Hasil penelitian menunjukkan bahwa pemberian tambahan cahaya LED kombinasi warna merah-biru secara siklus memberikan pengaruh yang baik terhadap laju pertumbuan tanaman krisan. Penambahan cahaya lampu LED kombinasi warna merah-biru dengan 1 siklus memberikan pengaruh paling baik terhadap pertumbuhan tanaman krisan yang ditunjukan dengan menghasilkan laju pertumbuhan tinggi tanaman tertinggi (y = 1.106x + 2.11), jumlah daun (y = 0.514x + 3.163), luas kanopi (y = 2.346x + 21.61) dan diameter batang (y = 0.082x + 0.168). Kata kunci: Krisan, produktivitas tanaman,cahaya LED kombinasi warna merah-biru, siklik, fase vegetatif. Chrysantemum cultivation in tropical region like Indonesia required the provision ofadditional light..The application of additional light is done by using artificial light fromelectric lamp in the evening for 4 hours after the sun set. This research determine the bestcyclic pattern to generate the highest growth rate. The application that had been given inthis research was the addition of LED lights of red-blue combination in a cyclic (off, on,off). Cyclic number given is 1 cycle, 2 cycles, 3 cycles, 4 cycles, 5 cycles and controls.The collected data were analyzed by regression analysis. The variables observed is plantheight, the leaves number, the canopy area, and the rod diameter. The result showed thatthe addition of LED lights of red-blue combination for one cycle gave the best impact forrate of growth of chrysanthemum plant. The addition of LED red-blue combination onecycle gave the best effect against chrysanthemum plant growth, which was showedproduced the highest growth rate of plant height (y = 1.106x + 2.11), the leaves number(y = 0.514x + 3.163), the canopy area (y = 2.346x + 21.61), and the rod diameter ((y =0.082x + 0.168).