An experiment was carried out to study the growth of Eucalyptus grandis seedlings produced in different sized tubes and N-P-K fertilization. A mixture of 80% organic compound (CO) and 20% charcoal powder fertilized with and without N, P and K was used as substrate. Four sizes of hard plastic tubes at the volumes of 50, 110, 200 and 280 cm³ were used as containers. The tube volumes must be considered for producing Eucalyptus grandis seedlings. Although the highest growths occurred in the larger tubes, these tubes should not be used because the seedling heights far surpass the ones considered as technically optimum for planting, and have a higher production cost. At 60 days of age, the seedlings are still small and quite tender, and do not present the hardness appropriate to field planting. At 120 days after sowing, the restriction to root growth and seedling height is affected even in the larger tubes, thus this is not the indicated age. The 110 cm³ volume tube must be considered for 90-day old seedlings.
Eucalypt; containers; seedlings and nursery
