Carrots

Why is NOVIC breeding carrots?

In relatively mild climates, farmers who can harvest carrots from October through mid-April have a crop to sell when demand for fresh produce is very high and when cash flow is often low. However, managing carrots for winter harvest can be particularly difficult due to weed management challenges, late season top degradation, and late season lateral root development.

Because carrots are generally slow-growing and have relatively short, sparse tops, managing weeds in carrot plantings is always a challenge. Holding carrots for winter harvest adds to this challenge because once the crop has developed a full foliar canopy and can no longer be cultivated, it may remain in the ground for up to six more months. During this time, the crop canopy remains static in size or begins to die back as quick growing winter annuals grow amongst and at times completely overtake it.

Another challenge particular to winter-harvested carrots is that carrot tops generally begin to degrade before April, making harvest more difficult. In addition, carrots often begin to grow lateral roots before April, greatly reducing their marketability.

NOVIC is breeding carrots because farmers who want to extend their season need varieties that have superior weed suppressive ability; strong, slow-to degrade tops; and minimal lateral roots into early spring. And they need all of this without compromising on texture, flavor, shape, or color. 

What is the breeding plan?

In the past three seasons plant breeder John Navazio and participating farmer Nash Huber have evaluated several open-pollinated carrots that may extend Huber’s season. They found that ‘Spring Market,’ a New Zealand overwintering carrot, was superior to the varieties Huber has traditionally used in terms of its unusually large, dense foliage that doesn’t readily degrade. It also exhibited slow development of lateral roots and excellent root quality into early April. Unfortunately, ‘Spring Market’ lacks the cylindrical Nantes shape and the deep orange color needed for his market. Huber and Navazio started a participatory plant breeding (PPB) project by crossing ‘Spring Market’ and ‘Rumba.’ ‘Rumba’ is Huber’s best late winter Nantes, with superior flavor, texture, and color. Huber and Navazio will evaluate and select the offspring of the ‘Spring Market’ by ‘Rumba’ cross for:

• weed suppressive ability,

• strong, slow-to degrade tops,

• minimal lateral roots into early spring,

• texture, flavor, shape, and color.

Which varieties are included in the trials?

Listed below are carrot varieties tested in years 2010 and 2011 of the project. In some cases, varieties were used in consecutive trial years. Visit the Organic Variety Trial Database to view trial results on the varieties below.