The British company Haygrove was started in 1988 as a strawberry farm, with a little over 2 acres of production in poly-covered high tunnels or hoophouses. Since then, Haygrove has expanded to nearly 250 acres of soft fruits, including strawberries, raspberries, blackberries, red currants and cherries, grown under plastic in England and Eastern Europe. Along the way, Haygrove’s owners decided they didn’t like the French and Spanish single-bay high tunnels they were using, so they designed and manufactured their own.
Today, Haygrove claims that half the United Kingdom’s strawberry production is grown in its tunnels and that it has sold 3,000 acres of tunnels throughout Europe.

Beginning this year, Haygrove tunnels are being erected in the United States. Ralph and Keith Cramer of Cramer’s Posie Patch in Lancaster County, Pennsylvania, bought the first range of Haygroves when they became a distributor for the company. A grower in Maryland has also become a distributor, and several others on the West Coast and in Hawaii are on the way to becoming distributors.

The main advantage the company claims for its tunnels is that they are less expensive than the hoophouses or cold frames most commonly used in the United States. One acre of Haygrove tunnels delivered, including steel, poly ropes and all essential parts, costs about 55 cents a square foot, or about $24,000. In comparison, the manufactured cold frames we use on our farm as unheated hoophouses cost us about $1.38 a square foot, or about $60,000 an acre with all materials included.

Because we believe that hoophouses can be of enormous benefit to market growers, we have been keenly interested in this cheap alternative. We have kept in touch with Ralph Cramer as he has experimented with them, and we went to Pennsylvania to see them for ourselves this summer.

It’s too early for us to pass judgment on Haygrove tunnels, and we want to emphasize that this article is not intended as an endorsement of these structures. However, we do want Growing for Market readers to know about Haygroves, so this article will describe the benefits and limitations of these structures so that you can decide for yourself whether they might be a good fit for your farm. We hope that readers who do purchase Haygroves will keep us informed about their performance.

Potential uses
The most important distinction between Haygrove tunnels and single-bay cold frames or hoophouses is that the Haygrove tunnels are not designed to carry a snow load, so they cannot be covered with poly during winter in cold climates. If your goal for a hoophouse is winter production, this is not the structure for you. Instead, you should be looking at a greenhouse or cold frame rated to withstand the kind of snow loads you normally experience.

Haygrove tunnels can be used to extend the season spring and fall by providing a few degrees of frost protection. Even greater frost protection is afforded inside a hoophouse when crops are covered with row cover. Eliot Coleman, author of Four Season Harvest, reports that a small tunnel of row cover held up on wire hoops, inside a hoophouse, provides 6 to 7 degrees of frost protection at 25°F.

Another good use we see for the Haygroves is for crops that require a chilling period, such as raspberries or tulips. In our hoophouses, which are covered in winter, the soil has stayed so warm during mild winters that we didn’t get adequate chilling for tulips. With the Haygroves, the plastic would be off during the winter, thereby exposing the crops to more cold.

The Haygrove tunnels can be used for production in summer, as well as spring and fall. Crops grown under plastic generally have higher yields and more marketable fruits or flowers because they are protected from wind, hail, excessive rain and, to some degree, insects. Because of the Haygrove design, the tunnels can be vented to provide temperatures nearly identical to ambient temperatures, or they can be kept closed to provide warmer temperatures for heat-loving crops such as tomatoes.

Design
The Haygrove is a multi-bay system with no walls between units. Each bay is 24 feet wide by 312 feet long. The structure consists of Y-shaped poles spaced about every 7 feet. The poles have an augur at the bottom, so they can be screwed into the ground, with 24 inches below ground and 48 inches above ground. Hoops are then inserted on top of the Y ends, creating an arch that is 13.5 feet at center – high enough that you can work inside the tunnel on a tractor.

Unlike greenhouses, Haygrove tunnels don’t need to be built on flat ground but can be built on slopes.
The poly covering on the Haygroves is held in place with ropes that are laced across the top, between the hoops. To vent the tunnels, the poly is just pushed up underneath the ropes. In winter, the poly can be gathered in the Y between bays, covered with black mulch and tied up with fishing line to protect it from UV rays while it’s not in use. On the outside walls, a sheet of plastic is attached to form side curtains. Adjoining bays can be separated with plastic side curtains when the grower wants to keep different temperatures in them. End walls are sheets of poly attached to poles that can be pulled back to form doors.
Our biggest question about Haygrove tunnels is whether they can withstand the strong winds in many parts of North America. Here’s what Ralph Cramer said:

“Haygrove has tunnels right on the North coast of Scotland where it’s very windy. All the tunnels that I get quotes for in the US are actually pretty deluxe, strength wise, because I automatically include the optional side bracing, top bracing and the 25% stronger grade of steel. In England and in many other milder climates, growers often opt to build without the bracing and use the cheaper steel to save on construction time and cost per sq. ft., but I felt it was best to include the bracing and stronger steel in every quote.

‘The hoops are normally spaced 7’ 3” apart. This spacing offers the best compromise of strength vs cost for most areas. In extremely windy areas, Haygrove has specified structures with the hoops spaced closer (6’) for added strength. This pushes the price up a bit, but compared to the cost of cleaning up a wrecked structure or the cost of moving to California, it’s worth it!!

‘Additionally, some growers in extremely windy areas simply add their own guy wires/anchors to the “Y” legs on the outside rows and/or to the top of the end hoops. This is done much like you would anchor a fence post. Sometimes, they just leave the end guy wires in place through their windiest season or they put a pole in 20’ or so away from the end of the tunnel and run a guy wire from the end hoop to the top of the pole and down to an anchor, much like they do for utility lines. The advantage of using poles is that the guy wire doesn’t obstruct the “headland” area. The anchors can be as simple as a 2’ piece of a pressure treated 4×4 buried 3’ deep in the soil “crosswise” to the direction of the tension with the end of the guy wire secured around the middle of it.

“Without the side and top bracing, fully vented tunnels have withstood 65-70 m.p.h. winds. Here in Pennsylvania, we had some pretty extreme thunderstorms this Spring and the tunnels did fine without being vented, just the doors were open. One time, we dropped the side curtains too (quick and easy), but I doubt it was necessary. We don’t get a lot of warning here because the thunderstorms pop up real fast, so running out and venting instantly was difficult to do before the storms hit. Unless they are in a protected area, the ends of the tunnels should always be towards the prevailing wind. Planting a windbreak is always a good idea as I’m sure all of you people from the Heartland already know!!!”

The augured uprights struck us as another good idea for strengthening the tunnels. While we were at Cramer’s, a mild storm wrecked one of our hoophouses. The upright posts on it are straight poles pounded into the ground. We had been told repeatedly that there was no need to cement them in, so we didn’t. But during this summer’s drought, the soil shrank away from the posts and a gust of wind got under the plastic and pulled the posts right out of the ground. Unfortunately, the result was that the hoops were twisted and about half of them will need to be replaced. It would seem that the augur would prevent the posts from pulling out as readily as ours did.

Pricing
Because Haygrove tunnels are made in England, shipping is a big part of their cost in the U.S. They are shipped by sea in containers, and the shipping cost will be the same whether the container holds an acre, a half-acre or a quarter-acre (the smallest size available). Growers wanting less than an acre should order together to share shipping costs. There is also a 2.9% duty.

Haygrove has come up with a special package for university researchers collaborating with farmers to do research on these tunnels. In this program, a farmer can purchase a one-third acre of tunnels (three bays 26 feet by 200 feet) for about 40 cents a square foot, with most of the money paid a year after they have been in use. Here’s how it works:
•The university pays $2,000 for the “consumables” such as poly and ropes. In addition, the university pays half the 2.9% duty and half the shipping (about $1,200 to the Midwest).
•The grower pays the other half of the duty and shipping (again, about $1,200).
•The researcher and farmer erect the tunnels and collaborate on a research project for a period of up to 18 months. At the end of that time, the farmer can decide whether he or she wants to keep the tunnels. If so, the farmer pays Haygrove about $5,000. (Prices aren’t exact because the exchange rate varies.) If the grower doesn’t want the tunnels, Haygrove removes them.
The basic Y-design of the tunnels is not unique to Haygrove. Similar tunnels are used in southern California, as well as in Europe. Some growers choose to have the structures made locally and claim they can do it for a much lower cost.

Payback
Ralph Cramer says he expects the tunnels to pay for themselves within two years, even with all the mistakes he made during his first year of production in them. Ralph is a flower farmer, and his main crop so far has been early sunflowers. He transplanted single-stem sunflowers in mid-April, about 4,800 plants per tunnel, and started harvesting sunflowers three weeks before his field sunflowers were ready. He charged 40% more for the early crop and grossed $10,000. He hopes to harvest a fall crop after frost takes the field sunflowers.
He stressed that the biggest management challenge he experienced was learning how to regulate the temperature in the tunnels. They heat up faster than he expected, so he advises growers to ventilate them early in the morning on sunny days.

Sources
•Ralph Cramer can be reached at 1-877-CRAMERS or 116 Trail Rd. North, Elizabethtown, PA 17022 or email rcramer@supernet.com.
•Haygrove’s web site is www.haygrove.co.uk