April 15 will be meaningful for at least two reasons next month. It’s not only the deadline day for filing tax returns, but it’s also the day the state’s Vidalia onions officially start shipment.

The crop’s yield last year suffered from higher-than-normal temperatures during the growing season, which caused smaller onion sizes, and the downy mildew disease. The mildew affected an estimated 20 percent of acreage in the 20-county south Georgia growing area.

The result of last year’s problems was a crop that produced one-third less onions than the year before and one that left many storage facilities unfilled.

Growers are more optimistic this year, according to state Agriculture Commissioner Gary Black’s office said. It expects less of a problem with plant disease and more uniform growth. Growers plan to harvest more than 12,000 acres this year.

The crop can’t be shipped before April 15, although there are exceptions to the rule. Black said shipping restrictions help ensure crops have matured and meet marketing standards.

“Onions that are harvested and shipped too early and do not meet the grade requirements can damage the reputation of this important crop,” Black said.