By: Alyssa L. Ochs
Hop growers spend much of the year planning and preparing for harvest, which is typically a busy time in the late summer through early fall. But once harvest season has wrapped up, there is still plenty of work to be done on a hop farm.
Hops by the Season
Running a hop farm is a four-season endeavor because there is something unique and important to do every time of the year.
In the winter, it’s time for trellis construction, planting cover crops and transferring potted plants to greenhouses.
Springtime is ideal for applying fertilizer, pruning primary shoots to prevent early disease, and tying twine to the trellis. Spring is also the time to establish training dates and install drip irrigation tubing.
When summer rolls around, hop farmers see the blooms occurring, monitor the crops to prevent loss to disease and pests, and plan for harvest between August and October.
In fall, it’s time to inspect the quality of the harvested crop, have brewers visit the farm to select hops, and plan for the first frost when plants go into dormancy.
While sometimes overlooked and not given the attention it deserves, the post-harvest season is crucial for hop growers as part of a year-around maintenance schedule. The tasks relevant to this time prevent pests and disease for the next season and help growers get their orders in well in advance, so they’re not rushing at the last minute. Meanwhile, post-harvest provides an opportunity to set up the next season for success by recalling lessons learned from the past growing season.
Soil maintenance should be at the top of the priority list for any hop grower’s post-harvest season. After harvesting the hops, growers can spend their time wisely by draining irrigation systems, cleaning filters, tilling the hop yard and planting winter crops or perennial cover crops. This time is also when growers can run harvested bines through a chipper to create mulch or add to a compost pile and fertilize the area to replace nutrients in the soil. Typically, applications of nitrogen—80 pounds per acre or less—are most effective. Fertilizer should be applied along rows, not on top, to prevent rot and disease.
Consider changing the irrigation frequency after harvest, and only irrigate if the area is experiencing a drought to prevent downy mildew and other diseases. To restore nutrients and increase the health of next year’s hops, add lime, potassium or gypsum. It is often best to apply sulfur to the field soil after harvest in small applications to lower the soil pH. It’s also a good idea to dig up a selection of plants to inspect the roots and assess the soil compaction, decay and lesions before simply replanting the crowns.
Pest and Disease Control Considerations
Hop growers can get ahead of pests and disease problems by paying more attention to these issues right after harvest. To fight downy mildew, a common problem on hops at this time of year, try using systemic fungicides and developing a protectant treatment program for next spring.
Other common insects to watch for in fall are two-spotted spider mites, damson hop aphids and potato leafhoppers. When high populations of these pests exist, it may be beneficial to apply insecticide in the post-harvest period. It may also be required to obtain a burning permit if burning pest-infested plant debris is allowed in the area.
Post-harvest Hop Drying
Also important is the post-harvest drying of hops to prevent mold and mildew, while allowing for proper storage to maintain high crop quality. This task is timely and relevant because harvested hops are rarely needed for immediate use. Right after harvesting, hops have high moisture content, often greater than 75% moisture contained within the fruit, leaves and flowers. Moisture content between 10 and 15% is ideal for preservation, but this may vary slightly based on hop varietal. Timely drying of hops will help preserve their flavors and aromas while keeping them fresh.
Growers can dry hops in ambient air with no heat added or use an oast to dry hops with temperature and air controls in a dedicated building or cabinet. Oasts can be convenient for large-scale hop producers but are often not practical or affordable for smaller hop growers with more modest crop yields. Alternatively, food dehydrators, ovens and microwaves are used by hop growers to aid the heated drying process. A drying rig can be used for the small-scale, low-cost drying of hop cones and other plant material where low-temperature drying is preferred.
Packaging the Hops
After hops are dried, it is time to store them in airtight packaging in a cool, dark, dry place. The hops should remain there until they are ready to be used.
Preserve hop cones and pellets in tightly sealed bags, while getting as much air out of the packaging as possible through manual pressing, vacuum removal, or nitrogen gas-assisted removal. Nitrogen purging is most effective but requires specialized equipment. Many medium-sized hop producers rely upon a food-grade vacuum sealing machine to package and store their hops in either multi-layer plastic or mylar vacuum-sealed bags. Hops are generally best used within a year of harvesting; however, properly packaged hops can often enjoy an extended shelf-life of up to five years.
Pruning and Trimming Considerations
Concerning maintaining the plants, this is the time to prune long stems off at the ground level. Top-dress hops with compost and mulch now too, which is especially important when winter temperatures drop below zero degrees Fahrenheit.
For infected hops, trim the bines short after leaf drop and then remove the debris. Cut at about two inches above the new crown buds for bines that are still green and not killed off from the frost. Then cover the remaining crown buds lightly with soil or mulch before winter comes. It’s best to get rid of weeds promptly, so they don’t lead to higher disease infections.
Trellis Repair Considerations
After harvest, but before winter is also an ideal time to inspect trellises and make any necessary repairs to the construction. If any trellis repairs are needed, stock up on supplies including anchor and interior pole materials, cable, anchor pins, clamps, staples, nails and wires. Tools and machinery potentially needed for the job include a tractor, shovels, cable pullers, hammers, sockets, tampers and a flatbed trailer.
Hop Stock Considerations
To prepare for the growing season ahead, start browsing different hops and the pricing from several competitors. This way, hop growers can learn about new varieties, the care they require and their general characteristics and benefits.
Contract Review Considerations
On the administrative side, early fall is an ideal time to review current contract options with trusted suppliers to secure high-quality hops for many years to come. Work on establishing good long-term relationships with suppliers and other relevant companies while reevaluating hop needs and plans for the future. Compare the cost options, and look into getting a private pesticide license if needed. Such a permit may be required in some areas for any use of general or organic pesticide on a crop for sale.
Other Post-harvest Tasks
Around this time of the year, make sure that trickle and drip lines and tape are drained and don’t have water pockets that could freeze in the winter. Cover lines that will remain in the field with plastic or mulch to prevent rodent damage. Growers with animals on their property can allow chickens or sheep back into the area to finish the cleanup process in the fall. Some hop growers even use hop bines as materials for winter wreaths as a side hobby or small business, so think creatively during any downtime after harvest.
Reflect and Reassess Operations
Post-harvest is also a valuable time to reflect upon the past season. Jot down a few notes about problem areas in the hop field or general operations to address anything related to nutrients, pests or other issues for next season.
With the craft brewery scene continuing to expand worldwide, now is an exciting time to be a hop grower and be such an integral part of the craft beverage industry.