Raspberries: Challenging but Potentially Profitable

“Raspberries are one of the more challenging crops I deal with,” says Maine’s vegetable and small fruit specialist David Handley. “I have more people get started in and get out of raspberries than any other crop I deal with.” People often see raspberries priced around $5 per half pint and plant the fruit. “But when the reality sets in as to how much labor is involved in getting the crop off the plant and to market in good shape, you see it’s worth every penny of that $5, and the

Growing raspberries in high tunnels can extend the growing season by several weeks, increasing yields and profits (and labor requirements) and enabling growers to raise varieties that aren’t winter hardy otherwise. Photo courtesy of Pennsylvania grower Wayne Breisch.

Growing raspberries in high tunnels can extend the growing season by several weeks, increasing yields and profits (and labor requirements) and enabling growers to raise varieties that aren’t winter hardy otherwise. Photo courtesy of Pennsylvania grower Wayne Breisch.

growers are earning their money. Lack of labor tends to be the downfall … The market is certainly there.”

Handley spoke at the November 2004 Farmer to Farmer Conference in Bar Harbor, cosponsored by MOFGA and Cooperative Extension, as did Kathleen Demchak of Pennsylvania State University and Jean Hay Bright and David Bright of BrightBerry Farm in Dixmont.

Site Selection

A raspberry planting should last 10 or 15 years or longer – if you start right. Plant in full sun and in a well drained soil with good organic matter. “Raspberries simply won’t tolerate wet feet,” said Handley. In addition to physiological problems, poor drainage can promote diseases, especially Phytophthera, a serious disease in Maine, particularly in wet springs. “I’ve had several plantings go down to it, even in what I thought were well-drained soils. Some varieties are more resistant than others.”

Drainage can be improved by adding organic matter, installing tile drainage, and growing on raised beds, where raspberries do well because “the bulk of the root system is in the top 8 or 10 inches; but you have to make sure you have adequate irrigation, and they may be more susceptible to winter injury.” Maintain a soil pH of about 6.0; raspberries tolerate a range of soil acidity.

In exposed sites, establish windbreaks before or at planting. “In Europe and New Zealand, some of these horticultural meccas, they don’t grow any kind of bramble or bush crop planting over an acre without a windbreak,” Handley noted. Wind shortens plants and can reduce yields and increase winter injury.

A gentle slope (8% maximum) and good elevation are desirable. Run rows against the slope, and don’t set plants at the top of the hill, where wind can be damaging, or at the bottom, where water and frost can settle.

Irrigation “is essential for the success of a commercial planting. Trickle irrigation is best. You can run it off of a well, or small pond if you’ve got a decent filtration system.”

Eliminate perennial weeds, especially grasses, before planting. “Quackgrass will come back with a vengeance. Going into a field that was in hay and carving out rows … and putting plants in is not going to work.”

Eliminate wild brambles within 500 feet of your planting – or whatever distance is practical – since viruses, endemic in Maine’s native brambles, are carried by aphids and leafhoppers. Windbreaks help with disease control, too, since aphids are weak flyers.

Life Cycle

Raspberries have a biennial growth habit. The above-ground part of the plant, the canes, emerge from buds on root suckers in the spring. The first, “primocane” year of growth is vegetative and has green “bark” or epidermis. Primocanes form flower buds in their leaf axils in the fall in response to short days. These buds stay dormant through winter.

Second-year canes that came through winter, “floricanes,” have brown “bark.” Buds that set the previous year now break and produce little branches called fruiting laterals, and flower buds on these produce fruit. The floricane dies after fruiting, and new primocanes that will produce the following year’s crop arise during the summer.

Everbearing, or primocane fruiting raspberries are different. Their primocanes form buds in the leaf axils and at the cane tips. The tip buds break and produce some fruiting laterals and a small crop in the fall. Buds lower on the cane stay dormant over winter, then break the following year for a summer crop, just like summer-bearing varieties. These canes die after fruit production.

Varieties

Only a handful of raspberries are winter hardy in our region. “‘Boyne’ and ‘Killarney’ are probably the hardiest.” They are reasonably early and have relatively short, stocky canes with lots of very fine thorns that aren’t bothersome.

‘Boyne’ fruit is small to medium and tends to be a little soft. This is the variety to grow in northern Maine; others are possible in southern Maine.

‘Encore’ ripens very late; and is a good bridge between late summer bearing and everbearing types. The fruit is large and of very good quality. Canes of ‘Encore’ came through the winter of 2003-2004 fairly well.

K81-6 is a good midseason variety with good fruit size, but it will have difficulty in a really hard winter.

‘Killarney’ fruits are a little bigger and brighter colored than those of ‘Boyne’ but ripen a few days later. Both are early to mid-season types.

‘Latham,’ a “fail safe,” very hardy variety, comes through most winters, seems to resist some common diseases and doesn’t have a lot of thorns; but the fruit is crumbly and medium sized with “a fair flavor at best.”

‘Lauren’ is only for the most protected spots or for very southern Maine. The fruit is very large and of pretty good quality, and plants are productive.

‘Nova’ is a “nice hardy one; good to follow up ‘Killarney;’ it’s just a little bit later. It seems to have very good winter hardiness and some resistance to the more common diseases.”

‘Prelude,’ a new everbearer, is even earlier than ‘Boyne,’ and Handley thinks its fruit is better, but it doesn’t quite have the yield of ‘Boyne’ and ‘Killarney.’ “If we get a long fall, it will produce a very late second crop, but in our area, a second crop is usually lost to frost.”

‘Reveille’ overwinters well, is very productive and has very large but soft fruit. “After having it at my place and at a grower’s place a little north of me, it came through the winters very well, was very productive … I would only recommend it for PYO. If shipped, it’s going to be mush.”

‘Taylor’ is “the row to have next to the house for yourself. It’s probably the best tasting raspberry out there.” Plants are reasonably tall and not too thorny. Fruits are not the largest but have excellent quality. Winter hardiness can be a little questionable, and it’s very susceptible to diseases, but customers will like it.

Everbearing Varieties

In New England, we want varieties that will mature their crop before the first fall frost, Handley pointed out – eliminating some popular everbearers. ‘Heritage’ is the top seller in nursery catalogs (although that’s changing as new varieties are developed), “but if you’re north of Portland, ‘Heritage’ is probably a no-go. South of Portland, in a protected site, it’s a possibility. At the Experiment Station in Monmouth, just south of Augusta, the first frost is usually Sept. 15, which is just about when ‘Heritage’ is starting to come on.”

‘August Red,’ probably the earliest maturing of the bunch, starts the first or second week of August. The fruit quality is OK, but plants are “small, wimpy and ugly” and not fun to work with. If you’re in a real early frost area and you want the late market, this is probably your best bet.

‘Autumn Bliss’ is about 10 days earlier than ‘Heritage’ and tends to overwinter better than ‘Autumn Britten.’ Winter hardiness “may not be an issue if you mow them and just use them for a fall crop” (discussed later).

‘Autumn Britten’ is a little later than ‘Autumn Bliss’ and about a week earlier than ‘Heritage.’ Some say its fruit is a little better than ‘Autumn Bliss.’ “I haven’t really seen that in my trials. It’s very similar in my opinion. ‘Autumn Bliss’ is more popular here simply because it’s a little earlier.”

‘Caroline’ is a few days earlier than ‘Heritage.’ It’s a tall, vigorous plant with lots of very good fruit. Growers much north of Portland may lose most of the crop. Handley had a great crop of ‘Caroline’ this year because of the long fall. Canes have little winter hardiness, “but as an everbearing crop, it works fairly well.”

‘Fall Red’ is about two weeks earlier than ‘Heritage.’ Fruits are small and of reasonable quality. Plants are very vigorous, considering the amount of fruit, and will try to take over. It’s vary hardy if you want to grow it for a summer crop.

‘Polana’ has ‘Heritage’ parentage and has impressed Handley. It’s a solid two weeks earlier than ‘Heritage,’ if not earlier, and is a relatively short plant. Fruit quality is not as good as ‘Heritage’ but is not bad; it’s reasonably sized and has “OK” eating quality, and its nice color “comes through processing for jam. I am pretty hot on ‘Polana’ now … If you haven’t done everbearers yet, it’s one to try.”

Planting

Buy one-year “handles” — primocanes that are dug in the fall, have the soil shaken off and are stored through winter – from a nursery. Plant these as early in the spring as you can work the soil; the longer the plants grow in spring, the more developed the root system will get, so more new canes will fill the row. (Tissue cultured plants are also available. See the Bramble Production Guide.)

Set plants at the same depth as they were in the nursery, generally in a trench about 10 inches deep. Spread the roots so that they’re not balled up; plants should have a good 10 inches of root growth. Space plants 20 to 30 inches apart in the row. “If you know you’ve got a variety that’s very aggressive, such as ‘Fall Red,’ you can plant them farther apart [2 to 3 feet], and you’ll have plenty of suckers coming up to fill out the row. If the variety is a shy sucker producer, like ‘Autumn Bliss,’ then you may want to buy more plants and put them closer … [otherwise] they’ll take longer to fill out the row.

“The distance between rows is generally where growers make their first big mistake. You need a minimum of 8 feet between rows, assuming you’re not trying to get powered equipment between those rows. If you’re planning on driving the tractor down there, you want 10 to 12 feet between rows.”

You can grow annual crops, such as lettuce and cucumbers, using about 6 feet of space between rows during the first couple of years. “But you really need that space, because once these canes start growing and arching over … it’s very difficult to get between them, unless you’ve left that space.” If you can’t get between rows to work, suckers fill the row middle, creating a solid block “that I call the dreaded raspberry patch.” Customers can reach in only from the edges. Fruit is wasted, and eventually plants die from disease or crowding.

Once planted, handles are cut to about 4 to 6 inches above ground, leaving just enough to mark the plants, in order to promote root and sucker growth rather than fruiting in the planting year so that the row fills. “Plus there won’t be enough fruit on there to make it worth your while to get the labor out there to pick it,” Handley noted.

Keep the planting clean cultivated (except for a potential annual crop between rows). You can apply a straw mulch in the planting year to keep annual weeds from re-emerging. Data suggest that this will increase growth, but “don’t leave straw mulch on in the second year,” Handley warned, because “the cool, moist environment promotes root rot.” He advised removing mulch early in the spring of the second year.

Trickle irrigation should be set up in the planting year to encourage root development and primocane growth. Trickle is better than overhead irrigation, which wets the foliage and invites diseases.

Maintain a 1.5-foot row width to ensure that canes in the middle won’t be shaded and lose fruit buds, and for good air movement. When suckers emerge beyond that width, run a cultivator or hoe through.

Fertilizing

Add compost and whatever nutrients are required before planting, according to a soil test. In June and August, after the plants have really started growing, add about 20 pounds per acre of nitrogen as compost, fish emulsion or other material. “Don’t fertilize after August 15,” said Handley. “This would encourage a lot of vigor when the plants should be going dormant.”

Second Season

In the second spring, you can establish a ground cover, such as a weak perennial grass, between the rows, “but you want a good 3- to 4-foot section with nothing growing on it but raspberries,” Handley notes. A bluegrass-fescue mix works well, but don’t use a conservation or contractor’s mix; these contain aggressive grasses. Avoid clover, too, because it will crawl into mulched areas. “Although it supplies some nitrogen, it’s better to get nitrogen from other sources.” You could include annual rye for a flush of green while the fescue slowly takes over. Handley likes a mix that grows so slowly that it has to be mowed only a few times a year.

You can add a 4- to 8-inch layer of coarse, forest-type mulch, such as bark or wood chips, after removing straw mulch that you may have applied in the planting row the previous year. “I’m not a big fan of sawdust [mulch],” Handley mentioned; “it packs and compresses. It can keep the soil too wet … or … [after] a real dry period, when water hits the sawdust, it tends to run off and not reach the root system.”

Fertilize in mid-April for early spring growth, as plants start to grow, with 20 pounds each of N, P2O5 and K2O per acre; apply 20 pounds of N again in mid-June (to encourage new primocane growth for next year’s crop) and mid-August (when fruit buds start to set); and maintain a soil pH of 5.8 to 6.5. If you suspected nutritional problems, tissue analysis (for P, K and Mg, especially) can be done in late July using the earliest fully expanded primocane leaves, but a soil test is better for routine fertilizing. “There is less variation in soil readings than in tissue readings, but if you suspect you have a problem, tissue analysis can give a snapshot of the status at a given time.”

T-trellis
A T-trellis is most common in Maine. Illustration from “Growing Raspberries and Blackberries in Maine,” by David T. Handley, University of Maine Cooperative Extension.

Trellises

Set up your trellis system in the first, second or third year. Putting this job off can save money in the first year or two.

A T-trellis — the most popular system in New England — holds plants so that harvest and other jobs are easier, and it prevents plants from flopping over when loaded with fruit. Put posts every 25 to 30 feet, with at least 2 feet below ground and 4 to 5 above, and anchor both ends of the row or support them with internal braces. Cross arms on each post should be 31/2 to 4 feet high (depending on variety) and about 31/2 feet wide. On each side of the cross arms, attach a wire, such as wire used for electric fencing. After pruning, attach canes to the wires with twine, rubber bands or tomato clips. These canes will fruit the following spring. When you stand at the end of a row, you should see a V, with plants spreading from the 11/2-foot row out to the width of the 31/2-foot-wide trellis at a height of about 31/2 feet. This spreading allows light into the center of the row for the emerging canes, and it keeps canes dry. If you maintained the 11/2-foot center row upright, new canes would come up outside of that row, where the light is, and to harvest, you’d have to fight through the thorny new canes. By spreading fruiting canes to the outside of the row, any new canes that come up outside of that row can simply be whacked off.

V-trellis
A V-trellis is stronger than a T-trellis but requires twice as many posts. Illustration from “Growing Raspberries and Blackberries in Maine,” by David T. Handley, University of Maine Cooperative Extension.

A V-trellis is another option. Sink two posts at a 20- to 30-degree angle every 25 to 30 feet, 2 feet deep, anchoring the end posts, and run a couple of wires on them. Attach floricanes to the wires. This system requires twice as many posts as the T-trellis, so it costs more but is sturdier and lasts longer; cross arms tend to be the weak point of a T-trellis.

Longevity

A planting takes three or four years to reach full production and lasts 10 or 15 years, average – or only five to eight on heavy soils. Handley has seen 25-year-old plantings that are still going strong, due to good management and excellent soils and sites.

Pruning

Summer thinning involves weed-whacking new canes outside of the 11/2-foot row two to three times. Weak, infested canes should also be removed. Wait until late winter or the following spring to remove spent floricanes, since these send carbohydrates to the root system as they die back. These have gray, peeling bark and old fruiting laterals; remove new, healthy floricanes that are outside the 11/2-foot row (these were green last year and have now hardened, with chocolate-brown bark, and have few or no fruiting laterals); remove weak or unhealthy canes; then thin the planting, leaving the tallest, thickest canes for a final density of three to four canes per linear foot of row, average. “They won’t be evenly spaced, because raspberries grow in clumps.” Compost, burn or take prunings to the transfer station to remove disease sources.

A simpler way to prune is to mow the entire planting. “If you mow off a regular planting of, say, ‘Boyne’ in the spring,” Handley explained, “you won’t get a crop that year; canes will come up, form buds and overwinter, then the following year, you’ll get a crop. If you could put up with a crop every other year, you could save having to prune.” Or, if you want a crop every year, you could mow one row one year and an alternate row the next.
Alternate-year mowing is done on some Southeastern farms to avoid labor problems. “This only makes sense if you have a lot of land. But if labor becomes your limiting factor, this might be something to consider.”

If you mow an everbearing variety in the spring, you’ll get a fall crop on the primocanes but you won’t get a floricane summer crop. You can mow these every year and grow another, summer variety with better fruit for the summer crop. “This is the way everbearers are generally handled … don’t start mowing until they’ve been in the ground for three years to get well established,” since mowing removes some plants nutrients.

Harvest

Handling this extremely delicate and perishable fruit “is a major issue,” according to Handley, and harvest may go from late July until a September frost, depending on your varieties. Try to pick fruit when it’s cool and dry – early in the morning but after the dew is off the plants. Pick into shallow, half-pints or even smaller containers rather than pints so that fruits are three-deep, maximum. “Many companies now make “clamshell” or small wooden containers that are broader and flatter instead of deeper.”

Cool berries immediately. Fans can move plenty of air; be sure to stack boxes so that air can circulate between layers.

Store the fruit as close to 32 degrees as possible. They won’t freeze at 32, because they’re loaded with sugar. Under good conditions, the fruit can hold for a week. If picked hot, in deep containers and transported in the back of the pickup, “in 24 hours they’re garbage.”

Marketing

The Pick-Your-Own market for raspberries isn’t that strong, because people generally won’t drive more than 20 miles for the fruit; and in the summer, people would rather be at the beach than picking fruit from thorny bushes. “It’s not like strawberries, where you can pick 20 pounds in a hurry.” Price is another drawback. “Even if it’s PYO, you’re still charging $5/pint, and people complain and compare that price with strawberries … but the same people will pay $6/half pint in the grocery store for something from somewhere else. I think you really have to look at the pre-picked market for a chunk of sales, unless you’re the exception to the rule.”

Pre-picking, however, creates labor issues. Ideally, harvest occurs every day or every other day. “This has been the downfall of a lot of raspberry growers who would otherwise have been successful.”

On the other hand, retail raspberries are always in demand, and people are usually willing to pay a good price for quality raspberries. Wholesale demand is good, too, but has storage and transportation issues. “Your name is on it but [wholesalers] control the quality. You really need to know how well the buyer is going to handle the fruit.”

Bottom Line

Establishing a raspberry planting will cost $3,000 to $5,000 per acre for good soil preparation, plants, trellises and labor. Maintenance beyond year 4, when plants are in full production, will cost $6,000 to $7,000. The net return runs from $0 (after a winter like 2003-2004, when you may not pick any fruit) to $6,000 per acre, which is better than strawberries. Yields range from 0 to 6,000 pounds/acre; that maximum is “doable” in Maine, but typical yields are 4,000 to 5,000 pounds. You should be able to get $1.50 to $3.50 per pound.

Jean Hay Bright & Kathleen Demchak
At the Farmer to Farmer Conference, Jean Hay Bright (left) talked about the raspberry planting that she and David Bright have established in Dixmont, Maine; and Kathleen Demchak from Penn. State U. addressed the potentially high yields of raspberries grown in high tunnels. English photo.

Big Yields in High Tunnels

Kathy Demchak and coworkers at Penn State have been researching raspberry cultivation in high tunnels for five years. “High tunnels,” explained Demchak, “are unheated greenhouses.” The sides roll up, and at Penn State, end pieces flip up and side wings fold out so that a tractor can get into the house. Their houses have peaked roofs to shed snow. Demchak noted that central Pennsylvania has had so much summer rain in the last couple of years that growers with raspberries under tunnels were the only ones to make money. She and her coworkers are also studying strawberry and hardy kiwi cultivation in tunnels.

All of her research is with primocane fruiting cultivars. “We do have some growers growing summer (July)-bearing raspberries. I’m not certain that’s the way you want to go … they’re not exposed to the elements, but the crop occupies the tunnel for the entire year, and you’re only picking it for a month.”

One impetus for her research was the fact that in outdoor plantings, so many berries were lost to frost. Comparing fruit picked with the number of blossoms and green fruit remaining at frost, Demchak and her coworkers found the following percentages harvested before frost:

‘Heritage’ 19%
‘Anne’ 27%
‘Autumn Britten’ 50%
‘Caroline’ 51%
‘Autumn Bliss’ 65%

‘Heritage,’ for example, starts ripening around Labor Day in central Pennsylvania and really gets producing around the third week of September; and the first frost usually hits in the first week of October. Also, thornless blackberries are frozen out every winter, so tunnels may enable production of that fruit.

On April 16, 2000, the researchers planted ‘Heritage’ and ‘Autumn Britten’ raspberries and ‘Triple Crown’ blackberries, with 8 feet between rows and 18 inches between plants. Demchak noted that growers normally can’t get into fields until mid-May, and this April 16 planting date turned out to be critical for getting a harvest in the fall of the planting year. The 8-foot spacing was used because the researchers weren’t using tractor-powered equipment and used a weed suppressing fabric rather than mowing between rows. Demchak really likes the flavor of ‘Autumn Britten;’ and its fruits are a little larger than those of ‘Heritage.’

No fungicides were required, and “five years later we still haven’t needed any — which was a shock to us, because grey mold typically is the problem in field production;” and almost no insecticides were used. Predatory mites were used to control two-spotted spider mites, and Neemix was used on Japanese beetles one year, but didn’t seem to help much. Organic fertilizers were applied based on tissue testing.

Demchak said that for field production in central Pennsylvania, a typical harvest for just the fall crop of the highest-yielding varieties is about 5,500 pounds per acre. In the tunnel, during the planting year (2000), ‘Autumn Britten’ produced 0.9 pounds of fruit/row-foot, or 4,900 pounds per acre, of marketable yield. “Suddenly, in the planting year, we got what we would expect in a three-year-old field planting!”

Marketable yields in 2001 were:

‘Autumn Britten’ (fall) 2.5 lb./ft. (13,600 lbs./A)
‘Heritage’ (summer) 0.75 lb./ft. (4,200 lbs./A)
‘Heritage’ (fall) 3.5 lbs./ft. (19,100 lbs./A)
‘Heritage’ (total) 4.25 lbs./ft. (23,000 lbs./A)
‘Triple Crown’ blackberries   3.6 lbs./ft. (19,600 lbs./A)

These yields “shocked the heck out of me,” said Demchak. “The percentage of marketable fruit in the tunnels is much more than in the field.” They did not keep ‘Autumn Britten’ canes for the summer crop, because they had only about 3 feet of potential bearing surface on the canes, “so we whacked them out and just produced a fall crop on them.” ‘Heritage,’ however, hadn’t produced much the previous fall, so they kept those canes for a summer crop. This research was done in a 17- x 37-foot research tunnel. (A half-pint clamshell holds about 5 ounces of raspberries.)

The plants started growing a month earlier in tunnels than outdoors the following spring – another reason for higher yields. “The season is six to eight weeks longer. This gives the potential for varieties that we might not be able to grow otherwise.”

Yields in subsequent years were:

2002

 

‘Autumn Britten’ 13,367 lbs./A, 80% as a summer crop
‘Heritage’ 20,100 lbs./A, 57% as a summer crop
2003

 

‘Autumn Britten’ 14,270 lbs./A, 61% as a summer crop
‘Heritage’ 14,621 lbs./A, 26% as a summer crop

Some grey mold appeared in 2003, a wet year, but no fungicides were used. The 2004 crop was still being harvested in November, so data weren’t available.

Demchak said that because they left so many canes for a summer crop in 2002, that’s when most fruit were produced. They thinned the summer canes to 5 per foot for 2003 and 2004 so that summer canes didn’t compete with canes that were coming up for the fall crop. So growers “can shift yields between summer and fall crops, depending on how many canes are there.”

Another planting of brambles, established in 2001, included ‘Heritage,’ ‘Deborah’ and ‘Josephine’ raspberries (‘Josephine’ is normally too late and winter-tender for their area but has good flavor) and ‘QD-F1’ Wyeberries (a red raspberry/blackberry hybrid) with 4 feet between rows and 1 foot between plants. It was fertilized with compost; planted on June 1; and not harvested in the fall of the planting year. “It’s critical to get plants in earlier if you want production the first year,” noted Demchak, but the cultivars they wanted weren’t all available until June 1. Regarding the 4-foot spacing, Demchak exclaimed, “Don’t do this! Resist the urge to put rows so close together! You always hear that if you have narrow rows and closer row spacing, you’ll have higher yields, so we tried it. Every grower who’s put in high tunnel raspberries has repeated this mistake.”

A similar field planting established outdoors for comparison didn’t produce any decent fruit.

Demchak noted that Wyeberries “look nice but have nasty thorns, and the plant really doesn’t want to give up those berries. They’re smushed by the time you get them off.”

With rows twice as close together as in the previous study, yields were cut in half per foot of row, so
total yields were the same. “There’s no reason to put rows so close. There’s a lot of shading and not much air movement, and it’s hard to work in there.”

Again, plants in these tunnels had very little grey mold or other diseases. In 2000 and 2001, two-spotted spider mites occurred in both experiments. “You change problems from what you typically see in field production to what you typically see in greenhouse production,” Demchak explained. In 2002, Japanese beetles were on the summer crop but were gone when fall berries came on. In 2003 and 2004, some leafhoppers and whiteflies were present, possibly because other crops in nearby tunnels had attracted them. Plant nutrition is of potential concern. “You’re producing a tremendous amount of foliage and fruit. We’re doing leaf analysis every year to guide our nutrition program.” Using compost for fertility may produce a salinity problem at some point, Demchak added, because the houses are relatively dry and salts aren’t flushed out by rains.

Estimating “a little on the low end,” Demchak projected 15,000 lbs./A total (summer and fall) yields. “You’re getting a lot of crop, but you’re also harvesting for a longer time than with field production.” Fruit size is about 50% greater; quality is improved; and berries stored up to 11 days “and still looked good.” Pesticide use was decreased markedly or eliminated.

A 21-foot tunnel (rather than the experimenters’ 17-footer) with three rows spaced about 7 feet apart and plants 18 to 24 inches apart is probably ideal. Both summer and fall-cropping is feasible for primocane-bearing raspberries because of the longer harvest season. Trickle irrigation is necessary.

‘Autumn Britten’ is still Demchak’s favorite. ‘Caroline’ fruits were a little smaller.

Demchak said that you can tip the primocane bearers and force them to produce more laterals, which will delay the crop about two or three weeks, “so growers are doing a combination of varieties and a combination of tipping and not tipping and getting nearly constant production.”

Yields in 2002, the year after planting, were:

  Summer Fall Total
  lbs./ft. (lbs./A)    
‘Heritage’ 0.4 (4,800) 1.1 (11,500) 1.5 (16,300)
‘Josephine’ 0.6 (6,500) 0.6 (6,300) 1.2 (12,800)
‘Deborah’ 0.5 (5,800) 1.0 (10,300) 1.5 (16,100)
Wyeberry 1.2 (13,500) ——— 1.2 (13,500)

Economics

A high tunnel costs about $5,000 for supports, plastic, labor, etc. Other costs (trellis, fertilizer, trickle irrigation, etc.) are the same as for field production, although you may pay a little more for plants, because they’re spaced closer than in fields. The big cost is harvest labor, estimated at $0.50 per half-pint.

With yields of 0.75 lbs./ft. of row in year 1, and 2.1 lbs./ft. of row in years 2 through 8, and receiving $2.50 per half pint, the profit is $942 per 17 x 96 tunnel, or $20,357 per acre. Demchak thought that the amount of work involved may preclude growers from keeping the planting beyond eight years, although that may be possible.

The following chart shows how profit changes with prices and yield:

Profit Sensitivity (per 17- x 96-foot tunnel)
$/half pint: $2.00 $2.50 $3.00
       
Half pts./tunnel/yr. Profit/tunnel/yr.
938 (1.5 lbs/ft.) $308 $161 $630
1250 (2.1 lbs./ft.) $317 $942 $1567
1563 (2.5 lbs./ft.) $942 $1723 $2505
1875 (3.1 lbs./ft.) $1567 $2505 $3442

Demchak noted that pollination is not a problem since the sides of the tunnel are open when flowers are being pollinated, even in October, for flowers that produce November’s berries.

From Quart to Clamshell

Jean Hay Bright and David Bright of BrightBerry Farm talked about their raspberry planting and plans. Jean started selling raspberries from her grandmother’s patch in Youngstown, Ohio, when she was 8 years old, for 35 cents a quart. Now she and David live on a sloping farm in Dixmont, Maine, that they bought in 1999 and have been developing since.

They plan to have 3 acres of raspberries, 1 of blueberries and 1 of annual crops in rotation. They’ve planted ‘Boyne’ and ‘Killarney’ for early-season raspberries, ‘Nova’ for midseason, ‘Taylor’ for late and ‘Polana’ and ‘Autumn Britten’ for fall bearing. They also planted ‘Jewel’ black raspberry, which overwintered and produced berries in 2004.

Plants are oriented on the contour of their slope for best exposure to sun, for erosion control and for level drip irrigation lines. Also, pickers won’t have to walk up and down hills to harvest an individual row. (They anticipate selling half of their planting as PYO and half retail or wholesale.) Plants are spaced 18 to 24 inches apart within rows, with rows 10 feet apart on center.

The field was clean cultivated at planting time; weed suppression “has proven to be our biggest problem in getting new plantings established.”

David emphasized that water is critical for berry production. “I’m a big fan of valves and quick connects” to avoid a long walk to shut down any part of the irrigation system, and to be able to shut off just part of the system for repairs or maintenance. The $40/A spent on shut-off valves for the beginning of each tape line “is worth every penny.”

He put a stake at the highest corner of his contour, then used a $10 “pop level” to find the contour and lay the first 100-foot section of drip line. “From there, make your 10-foot rows.” They use 15-mil T-tape, which will last for more than one season. If you use rigid plastic pipe for part of your irrigation, David said to bury it, “because you can’t maneuver around it. We’re moving toward having a lot of stuff underground.” Sunken boxes, their tops flush with the ground, can cover permanent pipes so that you can remove the top of the box and reach in to turn a valve.

The Brights are “draining their hillsides” into two ponds at the bottom, and they pump water from these into two 5,000-gallon tanks at the top of the hill, using gravity to feed water back down the hill through drip irrigation. Each of their water pumps has a filter, as does each header line. A pressure regulator keeps the water pressure at the required 8 to 12 psi, and pressure gauges signal potential problems.

David puts a hose fitting at the end of each drip line, opens it when he starts to irrigate to flush the line, then shuts it. The end of each row of tape is held down with ground staples, like those used on fabric row covers. “It’s amazing where the deer will take [the drip line] otherwise” before rows fill in. Flags (from Forestry Supply) signal places where they have ground staples and other parts of their irrigation system, and cardboard placed under various components keeps the grass down and enables them to find those parts.

David priced irrigation supplies for an acre at $527, or about $50 per year over 10 years. This does not include costs of the water supply or pipe and fittings to deliver water to the site.

Cheap, Quick Trellis

For a trellis, Jean simply pounds 4-foot hardwood stakes into the ground every 10 to 15 feet along each side of the row, across from each other, and wraps baling twine around the top of each stake for the length of the row. “You don’t need a post hole digger, and it works beautifully.” You can tie twine across two opposite stakes if the plants have vigorous growth. The string is about waist-high and lasts for a year.

Maintenance

Jean uses long-reach pruners (from A.M. Leonard or Kelco) to cut and grip canes, pull them from the row and put them in a pile. This tool, which comes in 4- or 5-foot lengths (Jean prefers the 4-foot), has halved pruning time. Canes remaining in the planting are about a hand-width apart in all directions. Chipped prunings mulch trees away from the raspberry planting. (Burning required a permit and wasted organic matter.)

Cane tips that are wilting due to borers are removed and put in black plastic bags as soon as Jean sees them.

Rows are kept weeded for good air flow and light penetration, and in case customers are allergic to flowering plants. Removing weeds also minimizes the number of stinging insects that customers are exposed to, and helps customers see the berries. Jean flags places where birds or wasps are nesting, and warns customers to stay away from them.

Harvesting and Marketing

Jean said that they do pick into some pint containers and have sold berries in pints and half pints. They do not let customers pick into their own quart containers, but provide new, green pint boxes as part of the PYO price.

They freeze 120 pounds to sell to Common Ground Fair vendors, putting the berries on trays and into a Sears Quick Freeze cooler, then putting them in 20-ounce Ziplock bags.

Having other fresh produce available helps attract customers to their farm, and Jean and David hope to add other products, such as ice cream or smoothies, pies or other deserts. They suggest thinking about traffic flow when designing your farm, including room for parking and for turning tour buses. Customers should have drinking water, restrooms or privies, and hand-washing stations available. Jean gets men’s shirts from used clothing stores and lends them to people who aren’t dressed appropriately for picking.

BrightBerry Farm charges $4 per pint for raspberries if they pick them, whether retail or wholesale, and $2.50 per pint if customers pick. They’ve had very little resistance to their pricing. They’re trying to get their clamshells, which hold 5 ounces of raspberries (but 6 ounces of blueberries and cherry tomatoes), into local Hannaford stores and paid $750 to start the process of getting a UCC barcode number and stickers. They also had to have a million dollar liability insurance policy for this market. Despite costs, Jean concluded, “The potential is great for a respectable income from a relatively small space.”

Resources

A. M. Leonard, Inc., 241 Fox Dr., Piqua, OH 45356; www.amleo.com.

Demchak, Kathleen, Jayson Harper and George Greaser, 2001, “Agricultural Alternatives – Red Raspberry Production,” Penn. State University Cooperative Extension, http://agalternatives.aers.psu.edu, Publications Distribution Ctr., The Penn. State Univ., 112 Agricultural Administration Bldg., University Park, PA 16802; 814-865-6713; kdemchak@psu.edu.

Handley, David T., 1996, “Growing Raspberries and Blackberries,” Bulletin #2066, University of Maine Cooperative Extension, Highmoor Farm, P.O. Box 179, Monmouth, ME 04259; 207-933-2100; dhandley@umext.maine.edu. (Also available from your local Cooperative Extension office)

Handley, David T., 1999, “Raspberry Varieties for Maine,” Bulletin #2172, University of Maine Cooperative Extension. University of Maine Cooperative Extension, Highmoor Farm, P.O. Box 179, Monmouth, ME 04259; 207-933-2100; dhandley@umext.maine.edu. (Also available from your local Cooperative Extension office)

Handley, David T., 1993, “Sustainable Raspberry Production in Maine,” University of Maine Cooperative Extension. University of Maine Cooperative Extension, Highmoor Farm, P.O. Box 179, Monmouth, ME 04259; 207-933-2100; dhandley@umext.maine.edu. (Also available from your local Cooperative Extension office)

Kelco Industries, P.O. Box 160, Milbridge ME 04658; 800-343-4057; www.kelcomaine.com.

Pritts, M. and D. Handley, eds., 2005, Bramble Production Guide. Northeast Regional Agricultural Engineering Service, $45.00 plus $6 s & h from NRAES, Cooperative Extension, P.O. Box 4557, Ithaca, NY 14852-4557; 607-255-7654; nraes@cornell.edu; www.nraes.org.

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