If vermiculite is chosen as the planting soil, all nutrition for the minituber plantlets will be depended on artification supply. For the first 15 days, induction nutrition is sprayed to promote roots spreading. The nutrition amount is not big since the plant is small. Fertilization period is one time per week .
After 15 days, fertilize the plant one time per week with nutrition based on MS perscription. To be notice, since the plants are still small, spraying fertilization should be adopted, when big enough, use root fertilization, if all condition permitted, dripping fertilization is also preferred.
In real production, if the cost of nutrition is too high, the solution of double-layer soil can also be considered. First, at the bottom of the planting basket, pave one layer of manure from cow or sheep, 1~2cm thick. Then use vermiculite for a 2cm layer. In this case, the plant will keep absorbing nutrition from underneath. To prevent the plants keep growing instead of tuberization, the growth inhibitor should be used on the leaves, for induct tuberization, but be very cautions about the density and frequency.
If the plantlets are growing in spring or autumn when the temperature is low, build up a small plastic tent for the warm keeping. In principle, the temperature should never be lower than 14 degree, most suitable is 25. If all conditions are good, the plantlets will survive after one week. Along with the growing, water consumption keeps growing, especially during the first 15 days, drought or overflow are not allowed. Therefore in the first 15 days, using spray irrigation and when big enough, dipping or watering. Thicken the vermiculite 2~3 times, it will increase the tuberization. The over-growth will have negative impact on tuberization, the best plant height is 30cm. Over that limit, use growth inhibitor to promote tuberization.