Meet Roundo and Olympo: Two New Long-Day Onions on Display at Future of Veg
Syngenta Vegetable Seeds is introducing two new long-day onion varieties at Future of Veg this August in Woodland, California. Roundo, an early-season yellow onion, and Olympo, a main-season white onion, represent the latest additions to a portfolio built around one principle: growers need varieties they can depend on. Developed with an emphasis on consistent bulb quality, strong single center percentages, and reliable bolting tolerance, both varieties reflect Syngenta’s ongoing commitment to breeding onions that perform where it counts, from field to packout. Attendees at Future of Veg will have the opportunity to see Roundo and Olympo in the field firsthand on August 11–13 in Woodland, California.
Grower Feedback Plays an Essential Role in Innovation
Every innovation in vegetable seeds starts in the field — with our customers. As Syngenta Vegetable Seeds’ onion breeding program expands, customer collaboration remains the foundation for how we develop, test, and refine new varieties.
“Grower feedback is absolutely essential,” says David Whitwood, Onion Breeder at Syngenta Vegetable Seeds. “The best opportunity for grower success is listening to the grower, pulling in their current requests and needs, and then putting that together in the germplasm we currently have to develop the best product.”
“The most important qualities that we breed for in onions are shape uniformity, and we’re also breeding for single centers and storability,” says Miguel Guillén, Product Specialist for the western United States at Syngenta Vegetable Seeds. “It’s a careful balance between agronomic traits and consumer traits.”
Disease resistance is also part of the equation. Syngenta’s onion breeding program incorporates a global approach to resistance, addressing challenges like downy mildew, Fusarium, and powdery mildew that can affect yield and crop quality across growing regions.
Roundo
Roundo is an early-season, long-day yellow onion bred for reliability and adaptability across diverse growing regions. With an average 105-day maturity, Roundo offers growers a premium, globe-shaped bulb in a colossal size, with excellent skin quality and a high percentage of single centers. Its strong agronomic package, including low bolting tolerance even under challenging growing conditions, makes it a dependable choice for both fresh market and processing segments. Roundo’s broad adaptability across different growing areas in the West US gives growers confidence that performance will hold across varying field conditions.
Olympo
Olympo is a main-season, long-day white onion focused on delivering the appearance and consistency that fresh market buyers demand. Maturing at 125 days, Olympo produces premium globe-shaped, jumbo-sized bulbs with exceptional skin quality and thin necks, the kind of packout quality that maximizes marketable yield. A high percentage of single centers, combined with reliable bolting tolerance, gives growers the crop performance and consistency they need from plant to market.
Innovation Rooted in a Global Perspective
Expanding a portfolio that performs across diverse growing regions requires more than local observation. Syngenta’s onion breeding program draws on germplasm from around the world, testing varieties across a wide range of environments to ensure that what reaches growers has been refined for both agronomic performance and marketable quality.
“We are building our portfolio to expand in all colors for the short day, intermediate, and long-day segments,” says Guillén.
That global-to-local approach shapes how every variety is developed. Products are tested across a variety of environments to help breeders predict, refine, and deliver what growers need in the field.
“What’s significant about our onion breeding program is that we are pulling in germplasm from around the world to pull together the best product for the local consumer,” says Whitwood.
Roundo and Olympo will be on display at Future of Veg in Woodland, California, August 11–13, 2026. Join Syngenta Vegetable Seeds in the field to see these new long-day varieties up close and connect with the breeders and specialists behind them.
All photos are either the property of Syngenta or used with permission.
Performance results may vary based on local climate conditions, geographic location, soil type, and growing practices. Consult with your local agronomist or extension service for region-specific recommendations.
© 2026 Syngenta. Some or all of the varieties may be protected under one or more of the following: Plant Variety Protection, United States Plant Patents and/or Utility Patents and may not be propagated or reproduced without authorization. The Syngenta logo is a trademark of a Syngenta Group Company.
