Sap Analysis Takes Progressive Hops Growers from Good to Great

Sap Analysis Takes Progressive Hops Growers from Good to Great

Gooding Farms in Idaho uses the world’s first blood test for plants to reduce plant pressure, increase bine height and improve crop yield.

What if a simple test could transform the way farmers approach their crop, giving them the tools to make in-season changes that minimize pest and disease pressure, maximize the nitrogen cycle, and improve crop quality and yield? Agro-K’s sap analysis provides the insights growers have been searching for by taking a real-time look at 21 nutritional indicators and their levels in the plant sap.

For Gooding Farms in Parma, Idaho, this testing has made all the difference in their hops. The farm, which spans more than 950 acres and grows 12 varieties of hops (including Idaho Gem™ Brand, a proprietary variety developed in-house), has experienced the science-driven results of sap analysis firsthand.

“Rather than relying on the science of sap testing, the farm had been doing things the same way for years,” says David Bloxham, Northern Rocky Mountain Sales Consultant at Agro-K and the person who first introduced Gooding Farms to the benefits of sap analysis. “They were putting on way too much nitrogen, and as a result, they were having a lot of mite issues and disease issues. With sap analysis, we were able to show them that they could address these problems more effectively and a lot sooner.”

The Importance of Proper Nitrogen Management

Some of the biggest issues Gooding Farms encountered each year were those common to hop growers across the country: spider mites, downy mildew, elevated nitrate levels. Each of these issues can be attributed to mismanaging the plant’s nitrogen cycle. While nitrogen is an important nutrient for growing tall bines and maximizing cone production, too much nitrogen can be detrimental to the growth process.

“Managing the nitrogen cycle is particularly important for this crop,” says Rick de Jong, International Business Development Manager for Agro-K. “Hops are very photosensitive crops that grow a bine from the crown to a wire that can be 20 feet in the air. In order to grow from crown to wire every year, the hops have to grow while the days are getting longer. After the longest day of the year, the bind will stop growing and start producing cones. The higher the bine, the more cones that grow. Because farmers are concerned with getting the bine to the top wire, they push the nitrogen applications.”

While some nitrogen is important, de Jong says, too much can back up the nitrogen cycle, preventing it from functioning properly within the plant. Sap analysis reveals when excessive nitrogen has become a problem because the report will show spikes in the plant’s nitrate levels. These spikes can ultimately lead to increased mildew and disease pressure.

Bloxham and de Jong worked together to help Gooding Farms to understand this vicious cycle. Using sap analysis, Gooding Farms tested two fields against one another. The first followed the nitrogen recommendations from the sap tests, while the workers maintained their regular nutrition program on the other.

“As the farm neared harvest, the block following the traditional program already had multiple miticide applications at more than $50 per acre per shot,” de Jong says. “The other part of the block, where the nitrogen was better managed, had yet to cross the threshold for a single spray. Managing that nitrogen cycle is really key to growing hops, and the sap is showing us what’s really going on inside that hop plant. We weren’t seeing it before sap analysis because we had no way of really measuring the total nitrogen cycle until now.”

Employing Science-Driven Nutrition™ for Better Hops

The benefits of sap analysis go beyond nitrogen management. The testing revealed other things, too. For one, Gooding Farms was suffering from water quality and management issues. When the farm endured a significant drought period, it would hammer the crops with water. As things cooled off, the workers cut back on the water to conserve resources, sometimes creating a water deficit in the process.

“With the sap analysis, we’re tracking old leaves and young leaves separately, which has given us a glimpse into nutrient mobility within the crop, which gives us guidance from a water management perspective,” de Jong says. “When the farm was in a water deficit situation, certain nutrients were not moving within the crop from the young leaves to the old leaves. If we don’t have enough water coming in, we don’t have enough water to move certain nutrients to where they need to be. On top of that, we don’t have enough water to start moving the sugars that then move other nutrients where they need to be. It becomes a cascading impact where we’re constantly playing catchup with the watering.”

The sap analysis also helped to illuminate some of the water quality issues Gooding Farms suspected were having an impact on crop quality. The operation had been on the fence about purchasing a sulfur burner to manage these issues. Sap analysis provided the final justification for taking the plunge. The expense, Bloxham says, has already been showing dividends.

Irrigation management and water quality aside, sap analysis also reveals which nutritional products are having an impact and which are a waste of time and money. After hops reach their maximum bine height, they go through a bloom and cone set period that require the right nutrients to support and drive the crop forward.

Boron and molybdenum are important during cone set, and potassium is essential for hops development from cone development to harvest. Potassium is the nutrient that helps manage heat stress and water regulation, but it also impacts how the alpha and beta acids build up in the cone—the process that determines quality, aroma and flavor. Those who mismanage the nutrient early will play a fruitless game of catchup for the rest of the season.

“With sap analysis, we certainly got a better understanding of which products were moving the needle, not just from a foliar application perspective but also from a fertigation application perspective,” de Jong says. “The growers were playing around with a lot of potassium thiosulfate through the drip system, and we found that the nutrient wasn’t really showing up when we tested the sap. When we switched over to a potassium acetate through the fertigation system, we saw that it was actually moving the needle.”

Sap analysis also revealed that Gooding Farms’ new overwintering program was successful. When the silica levels shot up significantly during the spring months, it proved that the crop’s root system benefitted from the gypsum and organic matter applied in the fall post-harvest.

“When we first started working with Gooding Farms, their silica levels were non-existent,” de Jong says. “Now, looking at how those binds with these silica levels came out in the springtime, we know that the crop has a solid base to grow healthier crowns. This really affirms to us that the operation’s overwintering program, which they spent a lot of money on, worked. We’re now seeing improved sap numbers and differences in the silica that will translate to stronger binds, less disease and insect pressure, and a bigger, higher-quality yield.”

Taking a Hops Grower from Good to Great

Sap analysis continues to inform Gooding Farms’ science-based approach to nutrition. In 2021, the farm has opted to test the crops continually. One week the farm tests 21 blocks, the next it tests the remaining 20. Because the operation is more organized and taking the nutrition recommendations more seriously, Bloxham says, the crop is thriving.

“Gooding Farms is really adhering to the program this year, and it’s showing,” he says. “They’ve been very pleased with the results they’re getting. Recently, they told us that they had improved yields and some of the best quality cones in the state. ”

This acknowledgement is just one of the many reasons Gooding Farms has embraced sap analysis. As the operation continues to sharpen its nutritional programs, it is finding new and better ways to manage product applications that improve efficiency and return on investment.

“Rather than randomly cutting back on fertilizer to save money, Gooding Farms is utilizing science to ensure that when they do spend money on fertilizer, it’s needed, it’s warranted and they’re getting bang for their buck because it’s actually working,” de Jong says. “That’s the power of sap analysis. It took a really good hops grower to the next level.”

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