Hops: A growing cash crop
AMES — While looking for a new crop to put into her research program, Diana Cochran, an Iowa State University Extension fruit specialist, said hops kept getting brought up in conversations, so she decided to dedicate some of her time to research them
Cochran said her hops research began back in November 2014. Eventually, in spring 2015, she planted an acre of around 100 hops plants.
Thanks to Iowa’s growing craft beer industry, interest in hops and hop production has grown.
According to Cochran when she first started at ISU a few years ago, there were only four or five growers in Iowa. However, there are more than 10 that have started their own hops production.
Based on conversations with growers, Cochran estimates there are 50 to 60 acres of hops being grown within Iowa.
Hops, she said, was originally used in beer production as a preservative, but now is used to help with flavor in the beverages.
In addition to beer, Cochran said hops have been used as sleep aides where she has heard of people stuffing their pillows with hop cones.
They have also been used for wreath-making and some medicinal purposes, such as hormone supplements.
Hops are a trellis crop. The vine, she said will over-winter in the soil and its typical growing season, depending on the spring and weather, is from April to August and flowers during the summer solstice in June.
When hops are harvested, the entire plant is cut down and sent through a harvester.
Hops, Cochran said, are a rapid-growing crop with typical growth of 18 feet in five to six weeks.
They require a heavy-duty trellis system which results in a big initial input cost to grow it.
Hops can be harvested in limited yields the first few years, but by the third or fourth year the vines should be in full productivity.
Hops have an expected plant life of 20 to 25 producing years, Cochran said.
The picking and drying process of growing hops, Cochran said, can be challenging as harvesting and drying systems can be expensive and hard to find.
“There’s definitely a lack of harvesters and driers, but some are being developed on a small scale,” she said.
After harvest, Cochran said hops are typically pelletized, however some growers prefer to use fresh hops.
Within her one acre plot, Cochran said she has eight different cultivars and two different fertility and irrigation studies being conducted.
In her cultivar trials, she is researching how each performs in Iowa in terms of disease and insect pressures.
“This research will help local growers understand what can best be grown here,” said Cochran.
Within her fertility trials, Cochran is working on verifying particular nitrogen levels and just what appropriate nitrogen levels that needs to be applied.
According to Cochran, depending on the soil type, the crop needs an estimated 70 to 75 pounds of nitrogen per acre its first year before requiring 100 to 150 pounds applied the following years.
Hops also like a lot of water. But depending on soil types, that could differ, so she has irrigation studies being conducted and is trying to fine-tune those irrigation levels.
In addition, her trails are considering Iowa’s high organic matter soils versus sandy soils, in which many hops around the U.S. are grown.
Cochran said the plant needs approximately 1.5 inches of rainfall per week, so with Iowa’s average of 31.5 inches of rain each year, she is providing additional moisture through drop or trickle irrigation.
“We are just trying to fine tune a fertility and irrigation program,” she said.
Cochran said she is hoping with her research to also assist hops growers in getting connected with one another.
Working with Erin Hodgson, an entomologist with ISU Extension, Cochran said they are gathering information and conducting producer workshops and hosting open houses to help growers start networking with each other.