Announcements

Job offersmore »



Tweeting Growers

Top 5 - yesterday

Top 5 - last week

Top 5 - last month

Exchange ratesmore »




US (UT): Soil heating, secondary plant covers influence high tunnel spinach

High tunnel (HT) winter production may be limited by extreme low air temperatures, suboptimal soil temperatures, large diurnal temperature changes, and short daylengths and associated low light conditions. To determine the productivity of spinach in extreme climates, HT production trials were conducted in the fall (October to December) and winter (January to March) of 2010–12 at the Greenville Research Farm in Logan, UT (lat. 41 N. elevation 1455 m).

Soil heating (±) using electric cables and secondary covers (fabric rowcovers and plastic low tunnels) were evaluated to determine combined effects on fall and winter spinach production. Soil heating significantly increased yield in all cover treatments in the Fall 2010 (F2010) trial when spinach was planted in November, but had little to no effect on plant productivity in the other three trials (more appropriate planting dates) even though it did increase soil temperature marginally.

The addition of secondary covers significantly increased plant biomass and leaf area when compared with the uncovered control. Excluding the F2011 trial when spinach was planted earlier under more favorable temperature and light conditions, the use of low tunnels resulted in significantly higher spinach yields (biomass and leaf area) than when grown under fabric rowcover. In the fall, relative growth rates (RGRs) decreased exponentially regardless of whether the soil was heated or not heated or if a secondary cover was used. This response was because of the seasonal decline in light levels and temperatures.

In the winter production cycle, spinach relative growth without covers was similar or increased as climatic conditions improved. For plants grown under fabric or plastic rowcovers, RGR remained more constant or decreased during the production cycle. Increased yields were possible with secondary covers as air temperatures increase more quickly in the morning, maintained optimal temperatures longer each day (higher growing degree hours), and retained trapped heat later into the evening. Statistical interaction between heating cables and secondary covers were rarely observed.

Fall and winter HT spinach production increases when further protection with secondary plant covers is provided; however, supplemental soil heating is not necessary.

Access the full study at HortScience.

Publication date: 10/26/2017

 


 

Other news in this sector:

12/15/2017 Ghana: Improving all-year availability of safe and fresh vegetables
12/14/2017 Organic fibre netting offers alternative to plastic in the fresh produce industry
12/13/2017 Japan's increasing interest in Myanmar's agricultural sector
12/13/2017 Hi-tech plug nursery (4 acres) opened in India
12/12/2017 Azerbaijan and Pakistan keen to expand agricultural cooperation
12/12/2017 Berry and nut industries in Australia get over $600k to develop new leadership
12/11/2017 "Horticulture industry NZ needs to innovate or lose competitive advantage"
12/11/2017 NL: New cultivation application QMS Mushrooms
12/8/2017 US (FL): Screen houses may help prevent grapefruit greening
12/8/2017 India: "Protected cultivation could double farmers’ incomes"
12/7/2017 India: Rainfall damage 90% strawberry plantations Mahabaleshwar
12/6/2017 India: Farming in the heart of a ‘dying’ city
12/5/2017 BVT reports on successful blueberry trial with honey bee dispenser
12/5/2017 6 things you need to know about potassium in aquaponics
12/5/2017 From the greenhouse to space
12/4/2017 UK: Grant scheme to boost productivity across Shropshire farms & food processors
12/1/2017 Zimbabwe urged to seek new ways to foster growth in horticulture
12/1/2017 CFAES helps increase agricultural productivity in Tanzania
12/1/2017 NL: RHP debuts video about quality mark substrates
12/1/2017 Vietnam: High demand in training of high-tech agriculture