- Growers Grow Greens for Winter Harvest in High Tunnels
- By Mary and Bill Weaver
Pennsylvania Correspondent
- Art and Kathy King, who farm with Art’s brother Larry in Valencia in western Pennsylvania, are innovative growers and marketers. This is their second year of growing lettuce and other greens for winter harvest in their two 16x96 foot high tunnels.
“Last year,” Art relates, “we planted lettuce transplants into the tunnels in mid-October. Unfortunately, we learned that full-sized lettuce is more sensitive to the cold than smaller plants, and all the lettuce did was survive.”
The growers used three layers of row covers over three-quarters mature lettuce plants. The plants withstood 10° temperatures, but it was January before they were able to harvest much. The size of the plants was the problem.
This past October, instead of using transplants, Art and Larry seeded their two high tunnels in Johnny’s Gourmet Lettuce Mix, which includes six varieties of lettuce. “We’ll cut them at four to five inches tall this year,” explained Art, “and sell them as a spring mix.”
In their half-length high tunnel, also in mid-October, the Kings seeded a mesclun mix, which is for late fall harvest and will not take severe cold, and an all-greens mix, including kale, mustard, and tatsoi. When we spoke with Art in late November, he said that the all-greens mix and part of the mesclun mix were ready for harvest.
Their winter greens and lettuce are sold to a local restaurant or two, and they have no difficulty moving all of their crop.
“We plant the lettuce in groups of four rows,” explained Art, “and put up wire hoops over that, then cover the hoops with a .5 ounce row cover. Growth has been very slow this year because of the lack of sunshine. In a high tunnel, your only heat is the sun, and when there’s no sun for days and days, everything grows very slowly.
Art recently asked William Lamont of Penn State Extension for suggestions. Lamont suggested replacing the row cover with a clear plastic with holes in it for the daytime, to admit more light and increase the daytime temperatures around the plants. Lamont suggested covering the clear plastic with a row cover at night, Art said.
Last year, aphids were a problem in winter high tunnel plantings, and were actually multiplying under the covers in January and February. The insect’s adaptability is amazing, said Art. “Aphids are an exception to insect rules. They reproduced rapidly. This year has been cold and wet, which is bad for aphids, so we don’t anticipate significant winter aphid problems this year.”
Last year, the Kings made a second winter planting of lettuce in their high tunnels in mid-February, and soon were harvesting 20 pounds of lettuce at a picking. “You’d never think there could be so many pounds of lettuce in there,” commented Art. “We just cut and cut and cut. We could have continued cutting longer, but the last week of April, we had to take the rest of the lettuce out so the tomatoes could go in the tunnels.” They are planning to repeat the mid-February lettuce sowing next February.
For tomatoes in their high tunnels, the Kings’ mainstay has been Sunstart. “We’ve been very successful with this,” said Art. In addition, they tried several other types of tomatoes last year. Juliet, a large grape-type tomato, “made us money, but the plants got seven feet tall. They were just out of control.”
Mountain Belle performed well in the tunnels, and brought $2 a pint at the local farmers’ market. They also grew some romas in the tunnels, but the prices for these were somewhat disappointing.
The tunnel tomatoes were planted the beginning of May last year, and are staked, using a Florida weave pattern. “This year,” said Art, “we may get a little more daring and plant the end of April. Our last frost can be the third week in May. We try to plant three to four weeks earlier in the tunnel than we could in the field. Because the heat in the tunnel increases the growing rate, we have tomatoes for market four to five weeks earlier. And because the tunnels keep the plants dry, there is almost no disease pressure at all, right through into October.”
Art does caution, however, that with the tunnel tomato crop, the grower must be extremely vigilant to watch temperatures in the tunnels. “Even when the weather outside is cold in May,” he explained, “on a bright morning, the temperature in the tunnel can quickly reach 120°, and at that temperature, the tomatoes will drop their flower buds. You need to be right there ready to roll up the sides of the tunnel to ventilate it before it overheats. Then you need to be right there again in the afternoon to roll down the sides to conserve the day’s heat.”
For the future, the Kings are considering growing seedless watermelons in their high tunnels, hoping to reap several advantages. First, they’ll have earlier melons. Second, Art explained, “Watermelons are temperature-sensitive. With the additional heat in the tunnels, we can produce better melons than in the field. And third, disease pressure will be cut, and not only because the foliage will stay dry.” The growers also reduce disease by covering the entire soil surface in the tunnel with black plastic.
Red potatoes are another crop the Kings are considering for tunnel culture. Their red potatoes are always grown with drip on silver plastic, to repel aphids, and are mowed rather than chemically vine-killed before harvest.
Another of the King operation’s innovations concerns their garlic, which they begin harvesting the third week in June. The Kings have neatly sidestepped all the work of drying garlic by selling their whole crop as green garlic, for $1 a stem.
Customers can use the bulb and the stem and the leaves, Art said. “People love it. With fresh garlic, they don’t have to peel the cloves.” Offering fresh garlic saves the grower time, as well. “We simply don’t have time to deal with drying garlic.”
The operation grows both softneck garlic, including California and Italian types, and a Canadian stiffneck garlic called Music. They plant 500 feet of row in early December, by hand, through black plastic. “The black plastic heats the soil and conserves moisture, giving you a larger bulb faster,” explained Art “We’re always the first at the farmers’ market to come out with garlic.”
The King’s extensive pepper plantings include Apple, from Johnny’s. “It’s a sweet red variety that we market as a supersweet pimento. It’s the sweetest pepper we’ve ever grown, almost like a Macintosh apple.”
Haricot Vert green beans are another recent addition to the King’s plantings. “We’ll plant some at each green bean planting to have a supply for restaurants,” he said. The pencil-slim beans “have no sense of stringiness at all, and they hold up to cooking. You can boil them a really long time, and they stay firm.”
Fava beans are another specialty bean variety grown, mostly for the ethnic Italian and gourmet market. “We grow two crops of 500 feet of row each, and they sell for $2 to $3 a pound.”
The Kings market their produce with well-established markets, selling, by the end of July, to five farmers’ markets a week and six restaurants that get deliveries twice a week.
Art is also vice-president of the board of directors of the Penn Corner Farm Alliance, which sells to 10 restaurants and four stores in Pittsburgh. The Alliance, funded in part by the Pennsylvania Alliance for Sustainable Agriculture (PASA,) gets very good prices, according to Art.
“The manager is a constant marketer of our produce. He talks directly to chefs and produce managers, and can relay details about quality. I tell him what I have to sell. He presents that to the customers, and gives me the order. I take the packed order to a regional drop-off site, and the Alliance delivers it. Then they do the billing and pay me.” Twenty-three farmers were part of the Alliance last year.
In addition, the Kings tried running a CSA (community supported agriculture) last year, after a friend suggested it. They had 11 members. “The response was very good,” said Art. “I made money and had a good time, and met some really nice people.”
Members picked up produce at the farm on Tuesdays from 4-7 p.m. Members took home three to four items that were mandatory and the CSA offered 10 to 20 other items, of which members could have a choice of six.
“We had memberships at two levels, one for $350, or an advanced membership for $400. The CSA lasted for 21 weeks, from the last week of May through October. Most members said they usually got more vegetables than they could eat in a week, so for next year, we’re offering fewer vegetables per week to accommodate that concern.”
“For the future, 400 members would be great! You can sell predictable amounts with a CSA, with only three hours of your time, and because we use a refrigerated display case, there’s not a lot of waste like there is at a farmers’ market.”
The King operation maintains freshness and quality, and it pays. They sell to several farm stands, one of which buys a lot of fresh green beans. “Even though they can buy green beans for $12 to $15 a bushel at the Pittsburgh Terminal Market, they prefer mine at $20 a bushel,” explained Art. “When they put mine out for sale, they know they’ll have no bad beans. (All are hand picked.) And if they don’t use the beans right away, they know they’ll keep well.
“We’re moving product so fast that it’s always fresh. The key to successful retailing today is postharvest handling - cool it promptly and keep it cold.”
Art has a degree in nature conservation, and is very conscious of soil erosion and soil quality. “None of our fields is more than 46 feet wide, and we have green grassways between all the fields, and seed most of them in a rye cover crop,” he related.
“We do a lot of mulching with straw, baling up to 800 bales of rye straw a year, and 90% of that is mulched, usually for erosion control on our hilly fields. We have a zero tolerance for erosion.”
