Sentence:  Disbudding is merely a species of pruning, and should be done as soon as the lateral buds begin to develop on the cane. It diverts the flow of the plant's <WSD>blood</WSD> from many buds into one or a few, thus increasing the size of the flower, [...] 
Meaning of the word marked with <WSD> tags:  The sap or juice which flows in or from plants.