Rhubarb is very easy to start from seed. Wet the seeds thoroughly, then keep them moist for several days until they germinate . Pot up the sprouted ones in individual cells. Transplant to the garden when the starts have at least 4 true leaves. Start as many plants as you have space for, then choose the strongest ones that best represent the typical traits of the variety. To save seed, allow only one variety to bloom in a given year to prevent unwanted crossing.