Some Info Re The Effect Of Latitude When Growing Hops

[billvelek]

The recommended latitude for growing hops is from 35 to 55 degrees in both the northern and southern hemispheres, but hops can often be grown outside that band. I have broken this post down into labeled sections in case you prefer to go straight to your own area of the world. After reading about your area or country, please continue with my "EVERYWHERE" section at the end of this post for additional information. Sections are as follows:
Australia
New Zealand
South Africa
U.S.
Canada
Europe
Asia

Australia:
In the southern hemisphere, the same recommended latitude band of 35-55 degrees applies. In Australia, only the southern portion falls within it -- south of a line from about Adelaide to Canberra -- but Perth and Sydney are well within that addition area above 30 degrees in which hops can be grown in the U.S., so perhaps it works there, too.

New Zealand:
All of New Zealand is in the preferred band.

South Africa:
For all practical purposes, all of South Africa lies below the preferred band, with most of it even lower than the marginal 30-35 degrees where hops are sometimes grown successfully, which is why electric lights are usually used to supplement daylight, as will be explained below.

U.S.:
Contrary to the impression that many people have, cultivation of hops is not limited to the Pacific Northwest in the U.S. -- Washington, Idaho, and Oregon -- despite that this is where commercial hop farming is concentrated; hops have been grown, with varying degrees of success, throughout _most_ of the continental U.S. Hops do _prefer_ latitudes between 35 and 55 -- which is everything in the continental U.S. that lies north of a line that runs from just north of Los Angelos and goes east across the Texas panhandle through almost the center of Arkansas and almost along the southern border of Tennessee and includes most of North Carolina; however, we do have reports, within my Grow-Hops group, of successful growers in South Carolina, Georgia, and even as far south as Austin, Texas, which has a latitude of about 30.25 -- and which is farther south than ALL of California, Arizona, New Mexico, Mississippi, Alabama, and Georgia, and all but the very bottom of Texas and Louisiana and the Florida peninsula. We also have a successful grower in Hawaii. So, hops should be _capable_ of growing in nearly all of the continental U.S. with the proper care, if anyone is interested in giving it a try.

Canada:
The recommended 35-to-55 latitude band covers probably 95% of Canada's populated area, including everything south of a line that runs east-west through _about_ the middle of British Columbia, Alberta, Saskatchewan, and Manitoba, and includes most of Ontario and Quebec. Unlike the additional 'marginal' band in the south (see U.S., above), I will be surprised if hops will grow _much_ farther north than latitude 55 degrees because of late frost days and cold temperatures which can't be remedied as easily as short daylight. But we do have a member in Sweden who is going to try, and I believe we also have members in Scotland (most is N of '55').

Europe:
The recommended latitude band of 35-to-55 includes almost all of Europe, including all of Spain, Italy and Sicily (although they are not known for growing hops), and excludes only part of Northern Ireland, and most of Scotland, Denmark, and countries around the Baltic Sea and north of Poland. However, we do have a member in Sweden who is going to give it a try.

Asia:
I'll mention part of Asia, too, since I've read a _few_ posts in brewing forums from homebrewers in Japan and South Korea -- almost all of those two countries lie within the preferred band, with the rest being inside the marginal band, so hops should grow there, too. China, of course, is a major grower of hops with plenty of area in the preferred band.

EVERYWHERE:
The problem with latitudes which are much below 35 -- actually probably below '30', since they apparently will often still grow okay from 30-35 -- is that the length of daylight is too short; yes, despite the hotter climate, 'daylight' is actually shorter in places closer to the equator because during summer in the southern hemisphere, it is lit 24 hours/day at the South Pole and dark 24 hours/day at the North Pole. But there is still a reasonable solution even below latitude 30 for any diehards out
there; in South Africa, for instance, which also has daylight which is too short, growers use electric lights to trick the hops into thinking that the daylight is longer, and the number of lights and their wattage is not as high as one might think would be necessary. In other words, for just a couple of bucks worth of electricity, you can still grow many times that amount worth of hops. However, an added problem in warm climates is 'vernalization' already discussed in another thread. More detailed info is available about all of this in our discussion forum.

Our 'Grow-Hops' Yahoo Group is less than nine months old but already has 1,012 members as of this post, and has been growing very rapidly in the past couple of months due to rising interest among homebrewers trying to find ways to ensure a supply of the hops they want at reasonable prices. If interested, please visit http://groups.yahoo.com/group/Grow-Hops

Cheers.

Bill Velek

 

[Duff]

Guess you boys growing hops at the Sunshine Coast and north - Lat. 25 and less - could be a case study in the concept of genotype x environment.

 

[Screwtop]

Guess you boys growing hops at the Sunshine Coast and north - Lat. 25 and less - could be a case study in the concept of genotype x environment.

Bugger: Latitude here -267847, last winter was pretty tame, didn't dig up the rhizomes to give em a winter in the fridge for a few weeks, not much chance of 'vernalization' so only had three flowerings this season

 

[lochrockingbeers]

Bugger: Latitude here -267847, last winter was pretty tame, didn't dig up the rhizomes to give em a winter in the fridge for a few weeks, not much chance of 'vernalization' so only had three flowerings this season

Wow only 3 flowerings! Makes me seriously question this vernalization vs production idea. I searched the past century's worth of scientific literature and could not find one source discussing hops rhizomes and vernalization. There were some relating to hops seeds needing vernalization prior to germination but that's a bit different. It is known in other plants but not all plants require vernalization to reproduce. Can anyone supply a reference supporting this (that isn't a website!) or I'll stick in the unsubstantiated old wive's tale camp. There are simply too many examples of hops growing and producing in parts of Australia with mild to non-existent winters.

I'm growing hops in not the most suitable place on earth but have no trouble getting them to flower, even the German varieties. And some of the American varieties are so vigorous and flower so early that they flower almost repeatedly for several months. The latter possibly has something to do with me letting the vines go and not cutting back new shoots. Not ideal commercially but fine for me.

 

[bindi]

Bugger: Latitude here -267847, last winter was pretty tame, didn't dig up the rhizomes to give em a winter in the fridge for a few weeks, not much chance of 'vernalization' so only had three flowerings this season

Ditto picked more yesterday [not as big a crop as the first 2 crops] but small flowers a starting for a 4th.
Same latitude, winter :huh: what's winter, It does get cold for a week or two will that do it? :lol: No chance.

 

[billvelek]

Reading the various replies which disprove the conventional wisdom which is given so often -- almost universally -- is GREAT news for me and other hop growers throughout the world. Not ever having tried to grow hops besides in my present location at latitude 35, and also not yet experiencing whether vernalization is a factor as I've read that it is, I therefore have no personal knowledge of such things and was only passing along a summarization of info from other sources which seemed to be reliable. Having read your responses, it isn't even worth my time to try to do any research on hop vernalization because I can't dispute your actual experiences ... and I'm not the defensive sort who feels that I need to justify myself or try to prove that I was actually right. You say vernalization isn't necessary, and I believe you, and I'm actually relieved that I was wrong and that I won't need to dig each crown up and refrigerate it each year; doing that would be a real pain in the butt and not something I'd want to do. In fact, that prospect, in itself, would probably be enough of a reason to dissuade many homebrewers in warmer climates from ever even attempting to grow hops.

The latitude part doesn't affect me, but I'm puzzled why commercial hop farmers in South Africa are known to install and run electric lights in their fields; I've seen pictures posted by one of our members in South Africa, as well as read literature about it. Maybe there are other reasons; perhaps this helps to bring on the flowers at an earlier time so they can be harvested before some seasonal rains hit, or something like that. I don't know. I am curious about the statement of "flowerings"; are you suggesting that you get a _distinct_ flowering, i.e., that all your bines and laterals all flower at one time, and that after picking you get another distinct flowering? I have had only one loooong period of continuous burring and flowering on my plants -- nothing even remotely distinct enough to say that I've had two or three flowerings. I could go out and pick everyday for awhile, picking only the largest cones which seem dry enough, because at that time I would have brand new burrs, and little tiny cones that were burrs just a day or two earlier, and some small cones, and medium ones, and large ones that are not quite dry enough.

Anyway, despite the apparent 'bad' info that I've disseminated -- in good faith -- I still hope that those of you who are interested will join our group. Sharing your personal experiences in 'Grow-Hops', as you have here, will help the hop growing and homebrewing community to learn what is accurate or inaccurate. We're now up to 1,034 members, so we still have a lot of collective experience with a lot more to come as new growers begin to share with us. Thanks for the replies and information; I will pass it along to our group.

Cheers.

Bill Velek

 

[lochrockingbeers]

Vernalization may still be valid with hops, at least it seems to be with hop seeds but there does not seem to be any genuine supporting evidence for rhizomes requiring vernalization that I could glean from anywhere other than a few mentions on websites, and information on the web is hardly ever scrutinised.

And hops do seem to go pretty well in many parts of Australia, although commercially it is confined to southern Vic and Tasmania where you should achieve better yields with longer summer daylengths. Not all varieties would require the same conditions so some I suspect like the German varieties will flower much more in southern parts of Australia. Some varieties are probably more tolerant of the heat so will do ok in northern parts of Australia. Would be interesting to see what effect the different growing conditions in Australia have on hop compounds for bitterness and aroma - a bit like wine terroir - i.e. a Cab Sauv from Margaret River and Yarra Valley tend to have different characters that define wine from these areas.

As for multiple flowerings, it is something that is probably not desirable if you were growing them commercially. You'd want them all flowering and ripening around the same time as several smaller harvests is more costly than 1-2 large harvests. I think the multiple flowerings with many growers here is a combo of vigorous growth of the first shoots in early spring combined with multiple later shootings that we don't cut down so you have different aged shoots. The conditions are still ideal for flowering so the later shoots flower after the first shoots have flowered. I suspect if you fertilise at say monthly intervals you could also induce extra flowerings. The different flowerings are quite noticeable even such that you may pick the first crop and the plant begins flowering again. Think of them as waves of flowering. I find it happens mostly with chinook and columbus, which are most vigorous growers for me.

 

[Ducatiboy stu]

From what I have read, Hops require long hours of light ( ie Twilight ) and cold to produce the flowers in abundance. The higher the latitude the less twilight Hrs, which is why the grow particularly well in Tassie & NZ. Of course this would vary with different varieties as the try to breed them to grow in diferent areas


Screwy..You could always black out your windows, fiddle the meter box and pretend you are a Hop lord....

 

[billvelek]

From what I have read, Hops require long hours of light ( ie Twilight ) and cold to produce the flowers in abundance. The higher the latitude the less twilight Hrs, which is why the grow particularly well in Tassie & NZ. Of course this would vary with different varieties as the try to breed them to grow in diferent areas ... snip

Actually, wouldn't it be that the HIGHER the latitude, the MORE twilight hours? Not only is daylight LONGER during the summer in higher latitudes, culminating in 24 hours of constant daylight each day at the South pole, but the closer you get to the pole, the lower the sun is on the horizon throughout the day and also the longer it stays close to the horizon after it sets, thus giving you more 'twilight' until, of course, you go far enough south that the sun doesn't set and you aren't getting any twilight.

Anyway, on the subject of "vernalization" and questions/comments by 'lochrockingbeers', my only source up to this point was http://pw2.netcom.com/~dluzanp/nov.htm but I just happened across a NON-internet source which appears to be scientific, of sorts. The following two quotes were posted in our Grow-Hops groups by a professional hop grower here in the U.S., so I presume that his reference material, which he refers to as his "bible", is considered as somewhat authoritative (I know that if I were growing professionally, I'd want 'professional' advice). His reference is to an apparent book titled "Hops" by R.A.Neve.

He first quoted R.A.Neve as follows:
"Dormancy is initiated by changes in the day length. The onset of dormancy is noted when the plant will not make new growth even though subjected to ideal growing conditions. Next will come the death of the shoots and finer root system and the transfer and accumulation of food reserves in the storage roots and the development of large resting buds on the crown. Experimental plants grown where there is no cold during winter broke dormancy erratically. Some were vigorous and some showed no growth at all." (emphasis in bold added by me)

He next quoted Neve, in a different post, as follows:
"Checking my 'bible' (Hops by R.A.Neve), I cannot find where a hard freeze is necessarily needed, however, experiments have been done where a 6 week period of at least 3 degreesC or less were necessary. (emphasis in bold added by me) The onset of dormancy is initiated by changes in the day length and involves the death of the shoots AND the finer root system, the transfer and accumulation of food reserves in the storage roots and the development of relatively large resting buds on the shoot system below soil level. If it stays too warm, the plants develop large fibrous root systems containing little storage material. The stored nutrients are not just for overwintering but for the huge growth in the spring. (emphasis in bold added by me) The breaking of dormancy is the result of ideal growth conditions and day length, at which point everything starts all over again."

So, once again, I am not disputing the empirical evidence of actual experiences of growers in Australia and South Africa, and I will accept your word that vernalization has been unnecessary down there; I'm merely offering up what I suppose is a scientific non-Internet source. By the way, just so we understand one another, what, exactly, do you consider a good crop -- regardless of how many flowerings you have. Commercially, in the U.S., growers engage in a single picking (bines are actually cut down for harvesting so it is impossible to get more than one picking), and obtain an average of from 1.75 to 2.25 pounds (.79 to 1.02 kg) of DRIED hops per plant. One homegrower with a plant on a chain link fence harvests about 2.5 pounds (1.13 kg) from one plant.

For better or worse, I have already begun my experiment and will post the results in about 6 months.

EDIT: By the way, our Grow-Hops group is now up to 1,096 members -- http://groups.yahoo.com/group/Grow-Hops

Cheers.

Bill Velek

 

[capretta]

thanks for the info guys.. good stuff.

 

[Ducatiboy stu]

Actually, wouldn't it be that the HIGHER the latitude, the MORE twilight hours? Not only is daylight LONGER during the summer in higher latitudes, culminating in 24 hours of constant daylight each day at the South pole, but the closer you get to the pole, the lower the sun is on the horizon throughout the day and also the longer it stays close to the horizon after it sets, thus giving you more 'twilight' until, of course, you go far enough south that the sun doesn't set and you aren't getting any twilight.


Um..yeah..

Basically the further Sth you go, the longer the twilight....

 

[billvelek]

Not to beat a dead horse, but would some of you hop growers mind posting some data about your crops so that we can do some comparisons and try to learn more about any effects of latitude and/or vernalization; I recently received a comment from a grower in South Africa who made this remark:

"I think you've hit the nail on the head by asking the growers with mild winters what their actual harvest is. I visited the guy who grows SAB-species hops here in Pretoria, and his plant is much less vigorous than my own, even though he is growing flowers throughout the season. When he saw my plant, his own words were that he was "blown away" by my crop. I think most amateurs don't realize how prolific hops plants can be, particularly just how much 1 kg of dry hops is on the plant. (I've harvested 300g, but the season is not yet complete).

Similarly with lighting: The pro's know how much extra crop the lighting gives. Even a 1/3rd crop will look fantastic to an amateur. The best way is to measure the weight of the dry harvest."

That has been backed up by other people, and then later I posted in this thread what I think is probably an authoritative source on the topics -- "Hops" by R.A.Neve. Also, I think common sense suggests that commercial farmers wouldn't be spending money on electric lighting unless it were actually profitable by increasing the yield of their plants. So, if possible, I would REALLY appreciate receiving the following info from any growers who would like to help us:
1. Your latitude
2. General assessment of how your winter typically compares with an average of "at least six weeks at 3 degrees C"
3. Variety of Hops
4. Age of Hops
5. Average and/or Last Yield per plant per year in DRY mass

Besides helping me and a lot of other hop growers, you might personally benefit from this comparison, too.

Thanks in advance for any help.

Cheers.

Bill Velek -- Grow-Hops now has 1,112 members -- http://groups.yahoo.com/group/Grow-Hops

 

[lochrockingbeers]

Not to beat a dead horse, but would some of you hop growers mind posting some data about your crops so that we can do some comparisons and try to learn more about any effects of latitude and/or vernalization; I recently received a comment from a grower in South Africa who made this remark: That has been backed up by other people, and then later I posted in this thread what I think is probably an authoritative source on the topics -- "Hops" by R.A.Neve. Also, I think common sense suggests that commercial farmers wouldn't be spending money on electric lighting unless it were actually profitable by increasing the yield of their plants. So, if possible, I would REALLY appreciate receiving the following info from any growers who would like to help us:
1. Your latitude
2. General assessment of how your winter typically compares with an average of "at least six weeks at 3 degrees C"
3. Variety of Hops
4. Age of Hops
5. Average and/or Last Yield per plant per year in DRY mass

Besides helping me and a lot of other hop growers, you might personally benefit from this comparison, too.


Bill

Nice idea and it could be beneficial but there are so many variables other than latitude, some of which like age of plant you have listed above. As an example, I'm sure I could get a much bigger crop if I let my vines grow taller but I am limited by the height of my lattice trellis and so the vines tend to fall back over each other, run horizontally etc. However, I harvest enough to use in many brews and I typically don't harvest the lot because I run out of storage room and time. The vines are also competing with a few other plants, although I suspect the reverse is more true. Location would also play a part as in are they in full sun or partly shaded. Soil type from full clay through to sand would play a part. Watering and nutrition is obviously vitally important, and every amateur grower will fall somewhere between over and under watering and fertilising. Summer temps. Disease? Pests? etc. etc.

These are just a few variables that will muddy any such data.

Also, although the book by Neve may be considered something of a hops bible, don't count on everything in the book being accurate. As the something for kate song goes "Believe everything you read and in twenty years they'll put you behind glass for all the people to come and see" . Textbooks often have mistakes or inaccurate author wisdoms, plus their information quickly dates as new research becomes available.

The 6 weeks at average 3 degrees C also needs clarification. How do they determine the average? I doubt even Australia's commercial hop growing areas achieve that. Bushy Park, for example, has mean mins of around 2C and mean maxs of around 11-12C during winter (From bureau of meteorology).

And I don't want to knock the south african hop growers using additional lighting but from my experience working in different sectors of the agricultural industry, you can never assume that a farmer does something because it is proven to be profitable. I've seen and heard of some bizarre farming practices, which are often as much about tradition and ignorance.

Sorry to be difficult. I forgot to mention that I haven't bothered weighing harvested hops - you'd better include accuracy of measuring scales too as another area of error.

Lochy

 

[mfdes]

Just out of interest, each string of this season't Tassie high alpha varieties will be earning the hop growers $400+ That's $1200 per plant (three strings is the norm) at the farm gate.
Gives you an idea of a) Yield and B) the effect of the shortage.

MFS

 

[Screwtop]

Just out of interest, each string of this season't Tassie high alpha varieties will be earning the hop growers $400+ That's $1200 per plant (three strings is the norm) at the farm gate.
Gives you an idea of a) Yield and B) the effect of the shortage.

MFS

Weight per bine or plant might have been easier to comprehend. Those following podcasts out of the US would be aware of the wildly fluctuating prices being bandied about. What are the growers receiving PKg for OZ high alph varieties?

Screwy

 

[mfdes]

AU$1100 per kilo of alpha acid. For a 15% variety, $165 per kilo TO THE GROWERS.

 

[Screwtop]

AU$1100 per kilo of alpha acid. For a 15% variety, $165 per kilo TO THE GROWERS.

Thanks mfdes, is that AA% of cones only or are complete bines consigned by the grower.

Screwy

 

[billvelek]

... each string of this season't Tassie high alpha varieties will be earning the hop growers $400+ That's $1200 per plant (three strings is the norm) at the farm gate.

... coupled with ....

AU$1100 per kilo of alpha acid. For a 15% variety, $165 per kilo TO THE GROWERS.

... and I deduce -- ($1,200/$165=7.27kg/plant=16pounds in U.S. weight) -- that you are claiming they grow about EIGHT TIMES the U.S. yield on their hop plants down in Australia. Frankly, that's a bit hard to believe. Have I misunderstood you or have I made a math error? It would be nice if you would be more direct and just come right out and say how many kilos of cones are produced per plant. Again, the U.S. average seems to vary from .8 to 1 kg -- or about .9 kg/plant. If they're really producing over 7 kilos per plant in Australia, then we ought to just quit growing them here in the U.S., because I don't see how we can possibly compete.

Cheers.

Bill Velek

 

[billvelek]

snip my list of questions for a survey to compare crop yields under a few conditions

Nice idea and it could be beneficial but there are so many variables other than latitude, ... I am limited by the height of my lattice trellis ... and I typically don't harvest the lot because I run out of storage room and time. The vines are also competing with a few other plants, .... Location would also play a part as in are they in full sun or partly shaded. Soil type from full clay through to sand would play a part. Watering and nutrition is obviously vitally important, and every amateur grower will fall somewhere between over and under watering and fertilising. Summer temps. Disease? Pests? etc. etc.

snip

The 6 weeks at average 3 degrees C also needs clarification. How do they determine the average? I doubt even Australia's commercial hop growing areas achieve that. Bushy Park, for example, has mean mins of around 2C and mean maxs of around 11-12C during winter (From bureau of meteorology).

And I don't want to knock the south african hop growers using additional lighting but from my experience working in different sectors of the agricultural industry, you can never assume that a farmer does something because it is proven to be profitable. I've seen and heard of some bizarre farming practices, which are often as much about tradition and ignorance.

Sorry to be difficult. I forgot to mention that I haven't bothered weighing harvested hops - you'd better include accuracy of measuring scales too as another area of error.

Lochy

You're not being 'difficult', Lochy. We're just engaged in a friendly discussion here, and you've pointed out some definite shortcomings in my limited survey. I was aware of those things but didn't ask because the more questions then the fewer growers will bother with participating, plus we would have difficulty quantitating many of those factors, and it would be impossible for most of us to deduce which factors were having more of an impact -- positively or negatively -- etc. So I just figured if we could get a reasonably large sampling, that all of those other factors would sort of 'average out', in that there are probably just as many growers in the U.S. dealing with just as many ancillary issues like partial shade, limited height, and improper watering/fertilization, etc. At least if we would see some sort of a trend, it would be a bit insightful. For instance, if the AVERAGE yield among Australian growers exceeds the average for the U.S. growers, I think we could absolutely conclude that vernalization and latitude have nothing at all to do with hop productivity. On the other hand, if the average for U.S. growers exceeds the average for Australians, then we could reasonably conclude that vern and lat might be factors and then possibly look more closely, depending upon the degree of disparity -- a small difference wouldn't justify any further investigation, while a large disparity would have greater implications. As for the "at least six weeks at 3 degrees C" criteria, that is the recommended exposure reputedly required for vernalization; if we are going to try to evaluate vernalization at all, we need a starting point, and I realize that I have been a bit simplistic in asking for a "general assessment" compared to that standard, which could predictably be expressed like "No way", "Hardly ever gets that cold", "Maybe just a week or two at that temp", or "Occasional periods below 3C, but never for more than a few days at a time", etc. But again, no one is going to provide a detailed chart of their temperature fluctuations, and even if they did it would probably be impossible, scientifically, to draw more than just a very general conclusion from it. I was just trying to get a 'rough' idea of if and when vernalization is occurring for different growers. Maybe it would have been better to ask for an assessment on a scale from 1 to 10 where '1' means full vernalization for '6 weeks at 3C' (which equals 42 days) and '10' equals 'none whatsoever' (zero days at or below 3C). But even that is problematic because there is likely to be a different effect for a grower who has 15 consecutive days at 3C compared to one with 15 non-consecutive days spread over a period of three months. I'm just trying to get some rough idea at this point.

Thanks for your interest. And by the way, if Australians are actually producing over 7 kilos of cones per plant, as I understood 'mfdes' to imply, then there is no point in going any further with this. YOU WIN!

Cheers.

Bill Velek

 

[lochrockingbeers]

AU$1100 per kilo of alpha acid. For a 15% variety, $165 per kilo TO THE GROWERS.

I'm a bit surprised by these numbers as well and Bill's maths seem sound based on the $1200 per plant claim.

So something like Suped up Pride of Ringwood and other high alpha varieties are seriously going for over $150 a kilo? What will this mean for the homebrewers' market: P.O.R. at $200-300 per kg! What does this also mean for the price of commercial beer?

mfdes, what are the usual prices per kg of dried hops in Australia paid to growers?

It is possible that Australia may have higher yields than other places but the varieties tend to differ. Also, worth considering is plant spacing.

As a side example, yields of Australian wine grapes can vary markedly as do the prices per tonne achieved by growers. Growers at Griffith in the Riverina can get up to 40 tonnes of grapes per hectare whereas other growers elsewhere may grow only a few tonnes per hectare and go for a higher quality grape.