Pick up know-how for tackling diseases, pests and weeds.
Farm bill, farm marketing, agribusiness webinars, & farm policy.
Find tactics for healthy livestock and sound forages.
Scheduling and methods of irrigation.
Explore our Extension locations around the state.
Commercial row crop production in Arkansas.
Agriculture weed management resources.
Use virtual and real tools to improve critical calculations for farms and ranches.
Learn to ID forages and more.
Explore our research locations around the state.
Get the latest research results from our county agents.
Our programs include aquaculture, diagnostics, and energy conservation.
Keep our food, fiber and fuel supplies safe from disaster.
Private, Commercial & Non-commercial training and education.
Specialty crops including turfgrass, vegetables, fruits, and ornamentals.
Find educational resources and get youth engaged in agriculture.
Gaining garden smarts and sharing skills.
Timely tips for the Arkansas home gardener.
Creating beauty in and around the home.
Maintenance calendar, and best practices.
Coaxing the best produce from asparagus to zucchini.
What’s wrong with my plants? The clinic can help.
Featured trees, vines, shrubs and flowers.
Ask our experts plant, animal, or insect questions.
Enjoying the sweet fruits of your labor.
Herbs, native plants, & reference desk QA.
Growing together from youth to maturity.
Crapemyrtles, hydrangeas, hort glossary, and weed ID databases.
Get beekeeping, honey production, and class information.
Grow a pollinator-friendly garden.
Schedule these timely events on your gardening calendar.
Equipping individuals to lead organizations, communities, and regions.
Guiding communities and regions toward vibrant and sustainable futures.
Guiding entrepreneurs from concept to profit.
Position your business to compete for government contracts.
Find trends, opportunities and impacts.
Providing unbiased information to enable educated votes on critical issues.
Increase your knowledge of public issues & get involved.
Research-based connection to government and policy issues.
Support Arkansas local food initiatives.
Read about our efforts.
Preparing for and recovering from disasters.
Licensing for forestry and wildlife professionals.
Preserving water quality and quantity.
Cleaner air for healthier living.
Firewood & bioenergy resources.
Managing a complex forest ecosystem.
Read about nature across Arkansas and the U.S.
Learn to manage wildlife on your land.
Soil quality and its use here in Arkansas.
Learn to ID unwanted plant and animal visitors.
Timely updates from our specialists.
Eating right and staying healthy.
Ensuring safe meals.
Take charge of your well-being.
Cooking with Arkansas foods.
Making the most of your money.
Making sound choices for families and ourselves.
Nurturing our future.
Get tips for food, fitness, finance, and more!
Understanding aging and its effects.
Giving back to the community.
Managing safely when disaster strikes.
Listen to our latest episode!
by James McClellan and Amanda McWhirt - August 9, 2019
Graduate student James McClellan shares what we have learned so far from a study being
conducted on the potential of growing hops in Arkansas!
During the Fall of 2018, a study was initiated at the University of Arkansas Fruit
Research Station located in Clarksville, Arkansas by Drs. Renee Threllfall, Jackie
Lee and Amanda McWhirt concerning the feasibility of growing Humulus lupulus, or hops, in Arkansas’ climate. The team is also working with two established on-farm
sites (Booneville and West Fork, Arkansas). This project is supported by a grant from
the Arkansas Department of Agriculture’s Specialty Crop Block Grant Program.
Although hops are primarily grown in the Pacific Northwest, the state’s burgeoning
microbrewery industry along with a general trend toward enjoying the unique aroma
and flavor profiles that hops impart on craft beer has piqued the interests of Arkansas
researchers, home growers, and microbrewers alike regarding the possibility of growing
hops in our region. Possible limitations to growing hops in Arkansas are the state’s
warmer, more humid summer days and fewer daylight hours which may limit optimal hop
cone development. Therefore, one of the major goals of this research trial is to evaluate
the potential for hops production in the state by assessing the rate of growth and
morphological characteristics of cultivars during their first year, including canopy
and lateral shoot formation, the impact of pruning at different times, node number
and location along bines, overall yield, and the susceptibility of the cultivars to
pests and diseases.
The trial at the UA Fruit Research Station is composed of nine 18’ plots, each planted
with six common hops cultivars (Cascade, Nugget, Zeus (CTZ), Cashmere, Centennial,
and Crystal). The cultivars are randomized within each plot and evenly spaced 2.5’
apart. An additional 22.5’ plot of nine hops (Cascade variety) is being used to assess
the effects of shoot pruning at three different dates. Each plot is separated every
twenty-four feet by a 15’ tall wooden post that supports a metal trellising wire.
Each plant has three training lines going to the trellising wire to support three
bines per plant. Prowl pre-emergent herbicide was used in September 2018 prior to
planting, and in late October of 2018 each hop was planted using a hand trowel and
immediately watered. Planting hops later in the Fall, while acceptable, is not the
only time that they can be planted. In fact, planting early in the Spring may be ideal
due to the longer growing season each hop plant will have before going dormant the
following winter. A small amount of compost was placed around each plant to conserve
soil moisture. The hops then entered a dormant state during the winter and all above
ground growth died back to the ground.
New growth shoots began emerging in late March of 2019, and assessments of plant survival
were taken on March 25. It was evident that several of the varieties struggled to
survive through the winter, especially the Nugget and Cashmere cultivars. Plants were
sourced from two locations in the fall of 2018 and differences in transplant size
at planting in October may have contributed in part to this observation.
Pruning Date Trial
There were 3 pruning dates: Early (April 15th), Mid (April 30th) and Late (May 15th).
Pruning involves cutting all newly emerged shoots to ground level in order to encourage
the emergence and rapid development of later bines that will be trained (Pictures
4 & 5). This trial was only conducted on a block of Cascade plants separate from the
variety trial. All variety trial plants were pruned on April 30th.
On April 30th, 2019 the first application of fertilizer (approximately 48.68g of 13-13-13
per plot or 8.11 g per plant) was scattered by hand. On May 15th, the second round
of fertilizer at the same rate was applied, Prowl pre-emergent herbicide (2qts/ac)
and a fungicide (Pristine - 28oz/ac) was also used.
Plant Vigor Assessments
On May 17th, 2019 most of the missing Cashmere hops plants were replanted and immediately
watered, and all remaining plants were assessed for regrowth. All cultivars, except
Zeus, experienced slow shoot reemergence. The missing Nugget variety plants were left
unplanted at this time due to a shortage of available transplants.
Training and Trellising
On May 31st, a hand-crank system was installed to the first wooden post which fed
a metal wire across the top of each 15’ beam in order to bolster and eventually lower
the bines to facilitate the harvesting process. Also, the third application of granular
fertilizer (97.36g of 13-13-13 per plot or 16.23g per plant) was spread by hand, and
multiple two-prong landscape fabric staples each with three 15’ pieces of bailing
twine attached were implanted at the base of all remaining hops and tied to the top
of the trellis wire. During the following week (started June 11th), the three most
promising, newly-emerged shoots from each plant were trained clockwise on the twine
(Picture 6) while any additional shoots throughout the remainder of the summer season
were cut back to the ground.
Picture 6: Zeus shoots (3) trained along twine - taken June 12th
Shortly after training, several tell-tale signs of insects (specifically army worms
and spider mites) and fungal disease (thought to be downy mildew) developed on the
foliage (Pictures 7-8). A weekly scouting regimen began on June 12th in Clarksville, and biweekly at other
sites. Pest scouting entailed randomly sampling 5 leaves from each plant and, often
using a watch repair eyeglass kit with a 10x magnification lens. Both sides of the
foliage were examined and any pests or diseases found were recorded and overall plant
health was rated according to the percent of foliage affected.
An initial fungicide spray application of 2.5lbs/ac of Aliette was applied on June
12th. An insecticide spray application (4oz/ac using Mustang Maxx) was sprayed June
19th. Biweekly, spray applications of both fungicide and insecticide (alternating
Aliette or Pristine with Mustang Maxx) commenced to control for pests and fungal growth.
The previously established, observational grow sites in West Fork and Booneville also
experienced infestations of army worms and downy mildew, so a backpack spray application
of Dipel (2tsp/g) in West Fork and a combination of copper and B.T. (Bacillus thuringiensis) in Booneville were spread on the 14th and 16th of June, respectively.
Once trained, each of the three shoots from all remaining plants continued growing
upward along the twine and each bine was checked biweekly for relative height to the
trellis wire, overall plant vigor (rated as poor, good, or excellent), presence of
flowers, and the formation of laterals to assess the progression of growth. Additionally,
one plant from each cultivar was flagged and photographed on a weekly basis for visual
documentation. Lateral shoots or side stems typically form at each node along the
entire length of the main bines (one or two laterals per node may form, 2 is most
common). Lateral shoots are usually where the plant produces flowers and eventually
the cones are formed (Picture 9) . For this reason lateral shoot production may be
a key indicator of potential yield.
Picture 9: Female flowers emerging from the lateral of a ‘Zeus’ bine in late June
The first data collection and observations on plant characteristics took place at
the UA Fruit Research Station on June 23rd and it was evident that the bines of the
Zeus and Cascade cultivars (variety trial and pruning study) exhibited the greatest
lateral shoot production, grew to the top of the trellis wire more quickly (Pictures
10-13), and had the greater plant vigor compared to the other four varieties within
the trial. Each bine was measured for overall height, the number of nodes were counted,
and it was noted whether each node emitted one or two laterals.
The other varieties, with the exception of Nugget which had one surviving hop plant
by the end of the summer, also grew and formed laterals over the course of June and
July, but not to the extent that Cascade and Zeus did. These three varieties also
showed flower emergence and cone set several weeks after Zeus and Cascade. During
the first week of July, nearly all Zeus and Cascade hops exhibited cone formation
along 2’-3’laterals while several of the Crystal and Cashmere cultivars produced flowers.
The remaining Nugget variety and all Centennial hops did not flower until the fourth
week of July.
No major visual differences in hop plant vigor were noticed between the different
pruning dates on Cascade. However in late June the “early” pruning date had a taller
plants, more nodes per bine and more nodes with 2 laterals. Later in July these differences
were not as evident and all of the pruning dates has similar measures of node number
and lateral number and all bines had set cones.
Pictures 14-16: Zeus bines reaching top of the 15’ trellis wire and beyond with cones
emerging from all upper laterals (July 11)
After the third date of data collection on plant characteristics, it was evident that
practically all of the Zeus and Cascade cultivars were ready to harvest based on several
factors: overall shape, texture, size of the cones, development of lupulin glands
within the hops cones, and the comparison to harvested hops at the observational grow
sites. During development, the hops cones feel compressed and moist to the touch,
and as they age the hops develop a distinct paper-like, crisp consistency and they
exude an aroma that is often compared to freshly cut grass or green onions when crushed.
Another sign that the cones were ready to harvest was the development of bright yellow
lupulin inside of the thin folds called bracteoles; these sticky compounds contain
the acids, aromatic oils, and resins that give the hops their distinct smell and taste
once dried and incorporated into tea or beer.
The hops are still being collected and analyzed at the Fruit Research Station and
at the University’s Food Science Department, and by comparing the latest data regarding
the physical characteristics of the cultivars alongside the harvest information, several
key takeaways are evident. Both Zeus and Cascade exhibited the most promising lateral
growth and cone development, and they resisted disease pressure to a greater extent
throughout the growing period. The Cascade cultivar produced slightly more double
laterals on average (standard and pruning study) while the Zeus variety displayed
the most rapid growth to the top of the trellis along with an earlier flowering time,
slightly longer lateral length, greater overall cone size and relative height to the
trellis. Within the Cascade shoot pruning trial, the data also indicates that the
bines cut down at the early or late times (April 15th and May 15th) have slightly
smaller average cone weight than the May 1st date. This is despite that the May 1st
planting data had slightly shorter bines and similar node and lateral counts. These comments are only based off of preliminary observations and comparisons of numerical
not statistical differences. Further analysis will be required to determine if these pruning dates impacts Arkansas
The remainder of the hops from these two varieties along with the Centennial, Cashmere,
Crystal, and Nugget cultivars are expected to be harvested on a weekly schedule over
the course of several dates in August. This information will add to the ongoing study
at the Fruit Research Station and allow the team of homegrowers and researchers to
assess the feasibility of hops production in the region.
Stay tuned as we will continue to keep you updated on this study!
Find the full report here.