INTERVIEW: Hops in the Heat – Root Imaging and Research on Hops at University of Florida

Plant Physiologist Shinsuke Agehara (University of Florida) sits down with Application Scientist Eric Munoz (CID Bio-Science) to talk about root imaging and growing hops in the subtropics.

TRANSCRIPT:

Eric:    Hi, my name is Eric Munoz. I’m an application scientist here at Felix Instruments, CID Bioscience.

Shinsuke:    Hi, my name is Shinsuke Agehara. I’m a plant physiologist at the University of Florida. I study crop stress physiology and crop management practices for vegetable and small fruit crops including tomato, strawberry, peppers. I also study new crops in Florida, including hops, [0:30] artichokes and blackberries. My main focus is stress physiology and, you know, in Florida heat stress is one of the major stress. So, I studied heat stress management for strawberry production, and I also study the basic crop management practices, nutrient management and irrigation and so on. And I do a lot of studies on roots too. [1:00] I have a rhizotron that we built in the built in the lab. So the one we use is the box one. You know, the root box with the transparent window. And so we try to focus on the root development in our soil, and then try to optimize nutrient management practice based on the root morphology, and also try to develop, you know, a root stimulating practice, something like that. [1:30] And we also use the minirhizotron that we purchased from your company, and right now we are using that for hops. And I don’t know if you are familiar with this crop but hops, you know, is an ingredient for beer.

Eric:    Yeah. Go ahead. I’m sorry.

Shinsuke:    Yeah. So, hops are typically grown in the Pacific Northwest; Washington and Oregon [2:00] and Idaho. And we are trying to see if we can grow hops in subtropics. And therefore, you know, the adaptation to the climate is the major challenge. So, you know, this is kind of related with stress physiology. So this is one of my projects here and we are working on many different management aspects, but we are also looking at roots; [2:30] how hops develop roots in our soil. And so that’s the main application of the root scanner.

Eric:    Oh, wow. Okay. That’s really interesting though, trying to grow hops in Florida. I know hops is a very important crop here in the Pacific Northwest, there’s a lot of breweries. The field has grown a lot.

Shinsuke:    Where are you located?

Eric:    Me, I’m outside of Portland, Oregon.

Shinsuke:    Oh, okay. Good. [3:00] So yeah, right in the area. Yeah.

Eric:    Exactly. My old company actually, it was a dietary supplement company, they grew their own hops for herbal supplements.

Shinsuke:    Okay.

Eric:    As a, you know, diuretic for…

Shinsuke:    Right.

Eric:    Yeah.

Shinsuke:    Okay.

Eric:    But CID Bioscience is actually in Washington, just alongside the river.

Shinsuke:    Okay, okay. Wow.

Eric:    Alongside the Columbia River.

Shinsuke:    Yeah. Pacific Northwest. Okay. Yeah. [3:30] I’ve been to Portland and Yakima, that’s where hops are grown.

Eric:    Yeah.

Shinsuke:    And to see the commercial production and, yeah. And so we didn’t have good success in a couple of past years, but that’s mainly because the environment is very different and the major limitation was that we don’t optimum daylight hours, [4:00] that we don’t have enough day length to promote enough vegetative growth before flowering. So we use supplemental lighting so we can change the photoperiod, and then we can control the timing of flowering. So, after that the project is going better, and because of the warm climate we can grow hops twice a year; so we have spring season and fall season. And so, that’s what’s unique about growing hops in Florida. [4:30] So, and that’s also making interesting to look at the roots, because they have kind of two growing cycles, which is very unique for a perennial crop. You know, normally a perennial crop, they have one growing cycle each year. You know? They produce, and then they go senescent and then go dormant and then they start over. Right?

Eric:    Yep.

Shinsuke:    But here plants go dormant, but only like for one and a half months. [5:00] Then they start the spring season two to two and a half months earlier than the Pacific Northwest. Then they can finish the first season by June and then right after that they start the fall season. So, you know, between the two seasons the growing habit is different. But you know, I also think that, you know, the roots, you know, the morphology development maybe also different between the two seasons. And then also, you know, [5:30] dormancy too. So…

Eric:    Yeah.

Shinsuke:    So that’s why we try to study using the minirhizotron.

Eric:    I see. So you haven’t collected any of that data yet. Have any, do you have any initial results possibly? Have you noticed any trends?

Shinsuke:    We have some data. Well, I would say images. We haven’t analyzed the images yet. So, we installed minirhizotron this spring. [6:00] So we started a new trial in the spring, and we installed… let me see. How many did we install? 3, 3, 9… Maybe between 30 to 40. So we installed at different positions for each plant, and so what we did is we installed one tube right by the ground. [6:30] You know, right by the, you know, the plant.

Eric:    Yeah.

Shinsuke:    And then we used another tube 12 inches from the plant and then another tube 24 inches from the ground. And the tube 24 inches from the ground is actually outside of the bed.

Eric:    Oh, okay.

Shinsuke:    So, one in the middle of the bed, just by the plant, one on the shoulder of the bed, which is 12 inches from the ground, [7:00] And then an additional camera tube, you know, outside of the bed. So we are trying to see how, you know, how much the roots can spread. And so, trying to see the vertical distribution, but also horizontal distribution of the roots.

Eric:    I see. My next question is, so are these are grown in beds, not in the field? And how… [7:30] and then for the soil, what kind of soil did you use? Were you using something that would, say, kind of imitate soil from Florida as opposed to, you know, possibly something from more of our region?

Shinsuke:    So, we grow hops outdoors.

Eric:    Outdoors.

Shinsuke:    Yeah. We make beds. Well, the beds are not tall. It’s just that we installed ground [8:00] cover, and that’s mainly for the weed control.

Eric:    I see.

Shinsuke:    And the weed management is very important in Florida because our climate is so warm, and the winter is short. So, we don’t really have a break for the weeds. They can continue to grow almost year round.

Eric:    Yeah.

Shinsuke:    And so we try to cover as much bare ground as possible. So, we put a ground cover [8:30] along the row, and then between the rows we planted grass so the bare ground is minimized. So, we don’t cultivate the soil. You know, we don’t till the soil between the seasons. But that’s, you know, we control weeds just by covering the ground as much as possible. And our soil is sandy soil; more than 95 percent is sand. [9:00]

Eric:    Yeah.

Shinsuke:    And so that’s also a big difference from Pacific Northwest. We have to change the irrigation and nutrient program based on our soil. And we have to use a lot of water, and during the peak time we put 6 gallons of water per plant every day.

Eric:    Wow.

Shinsuke:    Yeah. And we have, during the peak time, [9:30] 6 irrigation cycles a day: 6 times. And then each time we put about a gallon. Okay? And starting from approximately 8am, you know, 10am. You know, every two hours that we have. And it’s a lot of water.

Eric:    That is a lot of water.

Shinsuke:    Yeah. We have soil moisture sensor, so we monitor the moisture, but if you don’t put this much water the plants can get stressed. So, they use a lot of water. [10:00] They have a lot of vines, they transpire a lot of water. And then also the soil; it doesn’t hold the water well. So, you know, our irrigation program is pretty intense. And also nutrient program. I think we are applying, you know, not much higher than university recommendation. Like a typical recommendation.

Eric:    Yeah. So, why the interest in hops in Florida? [10:30]

Shinsuke:    So, I think, you know, the one is, you know, I mentioned we have two seasons; the spring and fall seasons. And our goal is to maximize the production in each season by, you know, optimizing the crop management practice and supplemental lighting. You know, changing the photoperiod. That was, you know, the first step. And now the plants are growing better, and so we have to [11:00], you know, redevelop the optimal nutrient program. You know, when plants grow, you know, better they require more. Then we had to find out what’s the optimum amount of nutrients to apply. So that’s why we are looking at the amount of nutrients we have to apply, optimum plant spacing. Initially we are using narrow spacing because plants didn’t grow so well. But with supplemental lighting plants are growing [11:30] much, much better. So, wider spacing we’ve found is better. So now we have to re-evaluate the plant spacing and many other things too. We are trying to see what’s the best pruning practice, and then also the timing of the supplemental lighting. We can control the timing of flowering by deciding when to turn off [12:00] the light. But that timing I think is important in each season. So the timing, we are trying to find out when is the best time in spring and fall. We also have to consider the hurricane season. We have hurricanes, that season is from, typically from June to September, that’s our peak time. So we are trying to harvest hops in June before [12:30] we might get hit by a hurricane. And then, so you know, trying to start the fall season when the plant, you know, like are starting from late June are already dry. And even when we have hurricane, if the plants are small the damage, you know, can be minimized. And another reason why we schedule the spring harvest in June is because we have rainy season, and we don’t want to [13:00] be picking hops, you know, when it rains a lot. So, there are a lot of things that we have to consider, and then try to, you know, optimize what we do based on our unique environment.

Eric:    Yeah. Well, that’s very interesting. Florida has, you know, it’s one of the most interesting areas for production, just because of it’s such… it has such a unique environment. [13:30]

Shinsuke:    Yeah, yeah. But we have a lot of craft breweries. So we have more than 300, and I think maybe about 100 just in Tampa alone. I work in a research center located near Tampa.

Eric:    Oh, I see.

Shinsuke:    So I know a lot of local craft breweries, and then they also support the project. And then, so I invite them to come to our hopyard to a sensory evaluation. And then we provide [14:00] hops to them so they can brew beer using our hops, and then we also do a beer tasting event and things like that. And so we have a market for hops.

Eric:    Yeah.

Shinsuke:    A lot of interest in locally grown hops. It’s just that, you know, it was not, you know, it’s not easy to grow hops here, so a lot of things to figure out, but  I think we are, [14:30] you know, I think doing better, and then coming up with a good practice now. This season our yield was more than 60 percent of commercial yield in the Pacific Northwest. And that was our first season yield. And you know, hops is perennial so it takes a couple of years to get the maximum production. So, we could get [15:00] more than 60 percent in just the first season’s yield. So next year it should go up. And then plus we have two seasons: spring and fall. So, when we combine the two seasons, even in the first year we can get almost the same yield as Pacific Northwest. And so we are excited now, and you know, we are hoping that we can develop a new industry here for growers and a craft brewery industry.

Eric:    Yeah, that’s very exciting. [15:30] It’s one of my… I mean beer is such a fun thing.

Shinsuke:    Yeah, yeah.

Eric:    And important. So, I think that’s really interesting work. Especially, you know, with those types of yields, initial yields. So, I really appreciate you for joining me on this session, Shinsuke. And I wanted to see… I want to, you know, keep in touch. Maybe we can do this again in the future. [16:00] I’d love to hear more about your hops experiment and research. You know, maybe next year after your initial… your first initial… Oh wait, did you begin this year? Or last year was your first?

Shinsuke:    We started the project this spring.

Eric:    Okay.

Shinsuke:    So, we’ve been collecting root images starting from the planting. So, and we are scanning those every two weeks, so we have [16:30] more than, I think… let me see. Like 15, 16 sets of images now, starting from the spring. So we are going to continue like year round so we know, you know, how roots are behaving during spring season, fall season, and then also in the senescence and dormancy. And then also after dormancy, you know, again the next growing cycle. [17:00] So, next spring we will have the concrete, you know, set of data for, you know, one year starting from spring of year one to, you know, spring of year two.

Eric:    Oh wow. Okay. Sounds great. Let’s plan to meet then and talk a little bit more about your research.

Shinsuke:    Sure. Anytime. Yeah.

Eric:    Appreciate it Shinsuke.

Shinsuke:    You’re welcome. Okay.

Eric:    Have a good day. [17:30]

Shinsuke:    Yeah, nice working with you, and have a nice day.

Eric:    Nice talking with you.