Pull apart the smaller tubers growing on the sides of the main large tuber. Plant both these small and main tubers. Cut up the main tuber into smaller pieces to grow more plants. Note that the larger the pieces, the larger the plant will grow.
Dip the tubers and seed pieces in a benzenoid fungicide with the active ingredient metalaxyl. Dilute with water per manufacturer directions. Use a pair of tongs or wear gloves during this step.
Lay out the seed pieces and tubers on a tray. Air dry for one to two hours in an airy location. Flip them and dry for another hour. Plant the dried and cured malanga seed pieces and tubers within two weeks.