Post-Harvest on the Hop Farm: Jobs Change, But Work Continues

By: Gerald Dlubala

After all the time and energy spent on vine training, pest-free growth and meticulous care that hop farmers put into raising the best possible crop, the harvest can feel like a whirlwind that’s over in a flash. Depending on the types of hops grown and the climate in which they are farmed, hop harvest can run anywhere from early August to late September. But the actual timeframe to get hops picked during peak ripeness and quality is a short, week to 10-day span.

  Hop ripeness and quality are directly related to the moisture content and alpha acid levels of the hop cones. Hops too high in moisture aren’t considered at peak alpha acid content. Hops harvested too late can degrade quickly in storage, be more susceptible to oxidation, and become more vulnerable to disease and pest contamination. Timing is everything, and sampling is critical to make sure hops are at peak ripeness.

  “It’s not that you can’t harvest and get good hops after that peak ripening period,” said Sean Trowbridge, co-owner of Top Hops Farm, LLC in Goodrich, Michigan. “It’s just that after peak ripening, the hop integrity comes into question and can result in product shatter during the picking process. Then you’re talking about the potential of considerable product loss.”

  Even when the harvest is completed, there’s little time to relax. When not evaluating the year in general, focus switches to working on sales and starting the farm tasks involving post-harvest sanitation, soil care, weed eradication and addressing any pest and disease issues that need attention. Since hops aren’t generally considered a pick and pack crop, there are several drying techniques to bring the moisture down so they can be stored safely without damaging the qualities that they bring to craft beer.

  “Immediately after harvest, it’s drying and baling time for the hops,” said Trowbridge. “Then we move 100% of the harvest to our pelletizers to have a fresh crop of current year hop pellets for the breweries.”

Fall is Spent on Cleaning and Maintenance

  “Cleaning, repairing and readying our equipment for next year is usually done in the fall. Just by their nature, hop cones can be pretty sticky, so after harvest, our equipment and work areas can get gummed up just with all of the contact with the hops,” said Trowbridge. “We take the time right after harvest to thoroughly clean the pickers, conveyors, belts, totes, wagons and anything else that gets used during harvest. Equipment like sprayers, whether boom or air blast type, need to be winterized. You know, it’s initially just a lot of manual work, cleaning and maintaining our equipment and getting our barns ready now for the next growing season.”

  Trowbridge told Beverage Master Magazine that after the equipment and buildings have been taken care of, late fall is generally spent in the hop fields on end-of-season responsibilities and plant management issues. Hopyard sanitation and cleanup is a critical function to get done right after harvest because it decreases the chances of disease and deters pest infestation for the next growing season. This also includes some type of weed suppression, usually by laying down a pre-emergent herbicide. 

  “As far as our hop yards here, we let our vines go into dormancy and apply a pre-emergent in spring. There’s no specific reason for that other than it seems to work better for us, and just like in farming in general, each farmer has his way of doing things that may not be the norm but have shown success in the past,” he said. “You still have to monitor moisture levels, because even after harvest, the hop vines need moisture for optimum winter survival. But once temperatures dictate action, we have to blow out our suspended drip lines and irrigation systems to prevent freezing and damage. Fall is the best time to get soil samples analyzed for pH to see what’s left in the soil and what needs to be replenished. Hops thrive in soil with a pH between 6.2 and 6.5, so fall is the time to make corrections if needed. Liming is common, but takes time to become widely incorporated into the soil.”

  Hop scrap can be a subject of contention. Some farmers take the hop scrap and compost it for use elsewhere. Others return the composted scrap right back onto the fields, while others take the scrap that’s not composted and spread it onto the fields. Every farmer has their opinion on the matter. The decision on what to do with the hop scrap is largely based on its condition. Were the hop vines healthy? Were there any signs of downy mildew or other diseases that can overwinter in clippings and on the ground?

  “Late fall is also when we switch our tractor to a mowing head and weed badger to cut all the remaining parts of the hop vines down. There’s usually about 1½ feet left of the vines after harvest, so we cut them and leave them be,” said Trowbridge. “Then, in spring, we go back over the rows with a brush head to remove all of the debris off of the plants and leave only clean rows for new growth. We won’t typically tear out or replace any vines that are healthy and productive. Good healthy rootstock can last fifteen years easy.

Some of the European heritage farms may have fifty to a sixty-year-old rootstock. Sometimes after about ten years, the Western-based hop farms will replace a portion of their hops with a more vigorous growing stock or different variety, but it’s not common. We’ve only done it once, and that was based purely on economics, replacing a portion of very low-income generating hops with a higher income-generating variety.”

Winter Involves Building Relationships And Business

  Trowbridge told Beverage Master Magazine that winter activities differ depending on where the hop is grown. West Coast farms can just keep growing, putting their harvest into the hands of brokers while they get back to producing more. In Michigan, Trowbridge first focuses on wrapping up sales for any product that remains unsold. Much of the harvest might already be spoken for, but any unsold product will be made readily available for anyone interested.

  In addition to sales duties, Trowbridge said that winter is typically the time to refresh and renew business contacts and associations and try to get more exposure for his farm. He uses the winter months to attend any conferences or expos put on by hop farmers associations or by the Craft Brewer’s Guild. He especially likes those that allow him to set up a vendor tent or booth so he can personally get his hop farm more exposure, make new contacts, refresh older ones and reach potential customers on a personal basis.

Growing Organic: Norton’s Hop Farm

  On the other side of the hop growing spectrum, smaller, organic hop farms have a different view of the post-harvest season.

  Don and Tina Norton maintain and operate Norton’s Hop Farms in Springfield, Oregon. Since 2008, they have grown Cascade and Nugget varietals on their family-run, certified organic hop farm. Because they’re organic growers, their post-harvest routine is a little different than others.

  “Well, we obviously don’t have to spend the time applying the herbicides or pre-emergent weed killers,” said Don Norton. “Most of my days are spent doing a lot of grass cutting and weeding out in the fields. We don’t chemically treat for unwanted growth, so it has to be continually weeded and mowed. We get a lot of blackberry growth in this area in addition to the grass and weeds, so it all has to be kept up with regularity. I do get basic soil testing done to see if we need to add lime and adjust pH levels in our fields. We don’t fertilize until just before we expect the new growth to appear, and that can happen in early January.”

  In between weeding and cutting, Norton spends time in the off-season on equipment maintenance as well as checking and winterizing his water and irrigation lines. He doesn’t have the same sales and marketing push that some larger volume farmers do because one of the benefits of being a smaller volume, organic farm, is that his product is generally sought after and already spoken for by regular customers.

  “We’ve sold to our local craft breweries in the past, but as of late, our harvest is sold to a locally well-known organic herb company—Mountain Rose Herbs in Eugene, Oregon. They need the whole flower of the hop, so we supply that to them. There’s also an emerging market for our hop cuttings and vines for use in-store or in other decorative displays, and also by local florists that like to use them in their creations.”

  “One thing that makes us different than a regular hop farm is that we don’t plant any cover crops or use any mulches in between rows,” said Norton. “Instead, we lay a ground cloth with holes cut out over the growing area for our hop plants to grow through. Doing it this way helps keep our weeds and grasses to a manageable level so we can remain organic.”

Email This Post Email This Post

Leave a Reply

Your email address will not be published.