Vermont Vegetable and Berry News Ė February 15, 2006
Compiled by Vern Grubinger, University of Vermont Extension
(802) 257-7967 ext.13, vernon.grubinger@uvm.edu
www.uvm.edu/vtvegandberry

NOTES ON NEWER BERRY CULTIVARS
(from Kathy Demcheck, Penn State University)

Here are some comments on some of the newer cultivars that I think are worth trying. As always, try small quantities until you determine how they perform on your  farm, and order early. Among strawberries, Itasca ô from the University of Minnesota, is a cultivar that we had in a trial as MNUS 138. At Rock Springs, this cultivar starting producing during the early season, but continued producing longer than other early-season cultivars. We compared Itasca to Earliglow, Evangeline, and Sable. Of those 4 cultivars, it produced the highest yields, in part due to its long harvest season, and had the largest berry size. The fruit color was bright red. The downside was that in warm weather, the flavor tended to become a little flat, and the fruit a tad soft, reminding me of Mesabi under similar circumstances. Because of this, this cultivar is probably better suited to the cooler regions of PA. Itís resistant to red stele. LíAmour, from the NY Ag Experiment Station at Geneva, bore its fruit in the early-mid season. It had excellent flavor, size, color, shape and resistance to foliar diseases. Compared to Honeoye, the standard for this category, the yields were considerably lower, but the quality was substantially better, especially when the weather got warm.

Canoga is not a new cultivar - not even close, but it is reappearing in nursery catalogs for use in plasticulture. I havenít had it in a trial, but the grower feedback Iím hearing is that growers are generally happy with the yields and quality. However, due to lower runnering than normal, if itís used in matted-row culture, it should be planted at a closer density than usual. It produces its fruit during mid-season. Ovation, in the late-season category, had excellent size, shape and flavor but the yields were a bit low in matted-row production. One grower mentioned that its production season seemed very short, so that might be something to watch for. That particular trait didnít show up in our trials, but location can make quite a difference. If youíre looking for a day-neutral strawberry, consider trying Seascape. Iíve heard that it may be a bit more susceptible to winter-injury than other day-neutrals, though it didnít have any problems with this at Rock Springs, even in gutter production the flavor is excellent.

In blackberries, you may want to try the new primocane-bearers Prime-Jim and Prime-Jan, especially if youíre in a location where cane winter survival has been a problem. Both are in a Penn State trial established in Landisville, PA, in 2005. The vigor, especially of Prime-Jim was impressive. These appear to have better flavor in northern trials than they did in their home territory trials at the University of Arkansas.

In the world of blueberries, there is a fair amount of interest in two late-season cultivars from Michigan State University, Aurora and Liberty, which are supposed to have improved flavor over Elliott. Several major nurseries are suppliers for the eastern US, but last year quantities available were really low. So, if you want to try these, order early.

A STUDY OF MUSTARD-GREEN SEED PRODUCTION IN THE NORTHEAST
by Jodi Lew-Smith, Sweetgrass Farm, Hardwick VT

Sweetgrass Farm received a 2005 SARE Farmer-Grower grant to assess the viability of direct-seeding mustard greens for seed crop production. The requirement for use of organic seed in the USDA National Organic Program rules, together with the boom in gourmet salad mixes, has increased demand for organic mustard green seed.  Mustard green seed production is an excellent enterprise for our cool Vermont growing seasons. Most Brassica species prefer cool conditions and, being not-so-distantly descended from weeds, can tolerate a wide range of soil types and moisture regimes. When grown on larger acreage, mustard green seed can be harvested with a combine.

In the large seed production regions of eastern Washington, Oregon, and Idaho, mustard seed crops are routinely direct seeded.  In the Northeast, mustard green seed crops have typically been grown by starting seedlings in the greenhouse and then transplanting them out to the field in early May, mostly to assure that plants will be flowering during the long day-lengths required to get good seed set. Previous trials have indicated, however, that certain mustard varieties are much more sensitive to day-length issues than others. For arugula, which is much less sensitive to day-length than some other mustards, we wished to see if it was possible to direct-seed the plants and still get a good seed crop.

We compared three different methods of direct-seeding: 1) broadcast seeding, 2) drilled seeding, and 3) drilled seeding of partially heat-killed seed (to reduce seeding rate). The three direct-seeded methods were compared to the control of transplanted seedlings. For each of the four treatments (three experimental and one control) we analyzed labor and expenses and compared those figures relative to the yield and percent germination.

The results show that the transplanting did produce a greater yield of seed than the other methods, but not by a highly significant amount. Relative to costs of production, the production cost per pound of seed was lowest for the drilled seed method, leading to the greatest potential return per acre. The broadcast method also shows promise, as it allows the earliest planting and affords the greatest weed suppression, however we planted it too thickly in our experiment to effectively assess yield, as the plants were highly overcrowded. The conclusion is that arugula can be successfully grown as a direct-seeded seed crop, at least in years where our early spring weather allows planting by the first of May, and possibly in wetter years using the broadcast seeding method.

Treatment              Labor hours         Cost          Expenses         Total Cost         Cost/pound
a. Broadcast              7.75                   $155            $29.70             $184.70             $3.24
b. Drilled                   13.75                 $275*          $4.95*              $279.95            $2.22
c. Drilled/Baked         45.25                $813**         $4.95              $817.95              $7.57
d. Transplanted         54.75                 $1095          $74.75              $1169.75           $7.65
*does not include time or expense of modifying grain drill to plant Brassica seed
** labor costs higher than planned due to weed issues, caused in part by overly-thin sowing

WINTER FREEZE INJURY TO STRAWBERRY CROWNS
By Sonia Schloemann, UMass Extension

Strawberries are susceptible to winter injury in two primary ways. The first is damage to roots from the heaving of soil that can result from cycles of freezing and thawing in the spring. This heaving action can snap roots and lead to problems with root infections in the wounded tissue. The other way in which strawberries can suffer damage in the winter is from freezing of crown tissue. The strawberry crown is actually a compressed stem
structure with layers of vascular tissue that forms a cylinder with vascular tissue running spirally in two directions. Inside this lignified or woody vascular tissue is a fleshy pith that can easily be injured and turned brown by the formation of ice crystals at low temperatures. The critical temperatures will vary with the variety of strawberry.

Most of our Northern varieties can withstand crown temperatures of between 10 to 14°F. This is why mulching for winter protection is so important for this crop. At these low temperatures, not only is the pith damaged, predisposing the tissue to infection by various pathogens, but the vascular function of the outer layer of cambium tissue can prevent normal transport of water and nutrients in the plant. Freezing injury is easily seen by cutting the crowns length wise and looking for damaged tissue. (Be aware that if left exposed to air for a while, this tissue will oxidize and turn brown like an apple when it is cut open.). Uninjured pith at the center is a creamy white when first cut. With slight injury to the crown, but not measurable in its effect on the plant, browning of the lower part of the pith occurs. Moderate injury, seen as a deeper browning, will result in noticeable damage to the plant (i.e., general weakening, slow growth, fewer blossoms and reduced yield), Lethal injury, where vascular tissue has been killed, will exhibit deep browning and blackening of the outer cambium and result in plant death.

If you suspect winter damage in your strawberry field, go out and cut some crowns a week or two after the ground has thawed. If a high percentage of crowns show severe injury, it may be necessary to plow the field down and enter into a rotation cycle for a few years. This will help purge the soil of high levels of pathogens that may build up on the decaying strawberry crowns. Low levels of damage can be nursed to better health by judicious irrigation, fertilization and other practices to keep plant stress low.

AGR-LITE INSURANCE SIGN UP DEADLINE IS MARCH 15

AGR-Lite is a whole-farm revenue protection package that covers most crops, animals, and animal products. The program is based on a 5-year average of revenue from Schedule F,1040, or equivalent tax forms. Coverage is purchased from participating insurance companies, but the cost is subsidized by USDA Risk Management Agency. For more information, contact Colleen Kisselburgh, ckisselburgh01@snet.net or 877-283-6540.

MANAGING HARVEST ROTS OF GRAPES, A SEASON-LONG PERSPECTIVE

This will be the topic of the New England Wine Grape Growers meeting on Mar. 15, 2006, from 10- 2, in Westport, MA. $35 fee includes lunch, reservations advised. Contact Sonia Schloemann, sgs@umext.umass.edu, or (413) 545-4347.

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