Studying the Type of Environment and Volume of Growth Media on Seedling Growth Characteristics of Marigold (Calendula officinalis L.)

Calendula officinalis L. is a herbaceous plant which is used as a herbal and ornamental plant. Nowadays, different materials are being used as seedbeds, each of which has unique characteristics. The soil texture which is used for planting C. officinalis must facilitate easy ventilation. This experiment was carried out on the basis of a factorial experiment in completely randomized design (CRD) with 26 treatments and four replications. The first factor included the types of seedbed at 13 levels and the second factor encompassed two types of volume for the seedbed i.e., 42cc (with 70 cells) and 24cc (with 104 cells). The seeds were planted in two types of seedbed with perlite, cocopeat, and peatmoss content and different proportions. The measurement characteristic included root length, seedling height, stem diameter, fresh and dry weight of shoot and root, and SPAD value. The result showed that the experimented treatments have a significant effect on most of the measured indices. According to the results of the effect of volumes and types of seedbed on the seedling of C. officinalis, the highest amount of leaf fresh weight, leaf dry weight, stem dry weight, and total fresh weight were observed in the treatment of 25% cocopeat and 75% peatmoss with the volume of 42cc for the seedbed; and the greatest content of fresh and dry weight of stem were observed in the treatment of 25% cocopeat, 25% perlite, and 50% peatmoss with the volume of 42cc seedbed. Perlite and cocopeat are suitable for seedbed because of saving water and causing porosity.