Drainage must also be maintained. Petals, which fall to the ground from spent blooms, are a potential disease hazard to the bulbs. For this reason the blooms are sheared off by a mechanical topper just before they pass their peak, much to the consternation of tourists visiting the fields. The flowers are picked beginning in late March. The exact time of the harvest varies due to weather conditions.
Bulbs remain in the ground until the summer when digging up and cleaning begins.
For the most part, human labor is used for the cutting of flowers while the digging, sorting and cleaning of bulbs has largely become mechanized. The amount of summer labor used by each grower depends on the farm size and ranges from 120 to 800 workers. These workers are usually part time farm workers and high school and college students.