91制片厂

DURHAM, N.H. - Researchers at the 91制片厂 have found that spinach grown in high tunnels during the coldest months of winter has the highest sugar content.

Becky Sideman, a researcher with the NH Agricultural Experiment Station and professor of sustainable horticulture production; Kaitlyn Orde, a graduate student in agricultural sciences; and Connor Eaton, a graduate student in plant biology; conducted a two-year winter spinach trial at the Woodman Horticultural Research Farm to determine the most suitable spinach varieties and planting dates for winter production in New Hampshire in an unheated high-tunnel environment.

"Spinach is a suitable crop for winter production in New Hampshire due to its ability to continue producing saleable leaves at very low temperatures. Fall transplants into high tunnels can result in winter-long harvests and significant spring yields, providing an avenue for growers to meet strong consumer demand for local greens during the off season," Orde said.

In both years, researchers found a direct relationship between temperature and sugar content, with colder temperatures in the days leading up to harvest heightening the sugar content in the leaves. The lowest sugar measurements were recorded during the warmest periods of the experiment (October, November, March, and April), and the highest measurements were recorded during the coldest months, February in particular.

Predictably, earlier transplant dates resulted in higher fall yields of spinach. For spring harvest, however, the researchers found that transplanting as late as mid-October did not negatively impact spring yields, and even the latest planting dates produced good spring yields. What this means is that the optimum planting dates will depend on the timing of growers' markets.

"The traditional growing season in New Hampshire is very short, limiting the period for local food production. Growing systems that allow for an extended period of production can help support agriculture in the state and supply more locally produced food on a more consistent basis," she said.

This material is based upon work supported by the NH Agricultural Experiment Station, through joint funding of the National Institute of Food and Agriculture, U.S. Department of Agriculture, under award number 228522, and the state of New Hampshire. Additional funding was provided by the NH Vegetable & Berry Growers' Association. For additional information about this research, visit .

Founded in 1887, the at the is 91制片厂's original research center and an elemental component of
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The , founded in 1866, is a world-class public research university with the feel of a New England liberal arts college. A land, sea, and space-grant university, 91制片厂 is the state's flagship public institution, enrolling 13,000 undergraduate and 2,500 graduate students.听

PHOTOS
Graduate student Kaitlyn Orde prepares to harvest spinach in February 2016. Credit: Ben Hill/91制片厂听
Here are two varieties of spinach with noticeably different growth habits, Emperor being more upright and Renegade more squat, on Dec. 11, 2015. Credit: Kaitlyn Orde/91制片厂
Undergraduate student assistant Talia Levy harvests spinach the week before Christmas on Dec. 18, 2015. The row cover you see at the end of the tunnel is removed for harvest and then replaced for added warmth. Credit: Kaitlyn Orde/91制片厂
Four varieties of spinach harvested on Feb. 19, 2016. Credit: Kaitlyn Orde/91制片厂