Selection and Propagation of Bog Blueberry Plants for Alaskan Food Security

Final Report for FW13-149

Project Type: Farmer/Rancher
Funds awarded in 2013: $14,688.00
Projected End Date: 12/31/2016
Region: Western
State: Alaska
Principal Investigator:
Charles Knight
Knight Farms
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Project Information

Abstract:

Planting rooted blueberry cuttings in the fall
Planting rooted blueberry cuttings in the fall

Rooting blueberry cuttings in misting chamber
Rooting blueberry cuttings in misting chamber

Bog Blueberries ready to pick
Bog Blueberries ready to pick

Wild blueberries, Vaccinium uliginosum, are highly desirable in Interior Alaska. They are found throughout the circumpolar north, but the plants are short and harvesting is slow and laborious. Nobody is growing these berries commercially, and harvesting equipment has not been identified that will work well on this species. There is a lot of variability among blueberry plants in the wild. Some of these differences may be due to genetics, and some may be due to site conditions. Our goal was to identify the best blueberry plants in terms of yield potential and bush structure adaptable to mechanical harvesting, and to reestablish those plants on uniform sites on our farms where they could be selected and propagated for commercial production. The challenges include: identifying superior plants, propagating the plants, developing cultural practices for growing the plants, selecting or developing a mechanical harvester for the berries, and developing a market for the berries. This project focused on selecting superior plants from the wild, propagating those plants, and moving those plants to uniform sites on farms.

At the beginning of this project, we knew where many of the best berry picking areas were in Interior Alaska. We started by collecting berries, extracting their seed, growing seedlings, and evaluating for superior qualities. This is a long process and the desired characteristic of the mother plant might not be expressed in the seedlings. Thus, it was difficult to determine if the desired trait was actually genetic or site related. Next, we learned how we could propagate the blueberry plants by softwood cuttings. This process had several advantages over propagation by seeds. The softwood cuttings are genetically identical to the mother plant and collection time for softwood cuttings is ideal because they can be collected at the same time one is picking berries and surveying a lot of plants. We rooted the cuttings under a misting system in a greenhouse, transplanted the cuttings into individual pots, and overwintered the plants. Then we lost a large percentage of them the following summer. We hadn’t considered that our irrigation water might be so hard that minerals in the irrigation water would overpower the soil acidity in our small pots and the small plants wouldn’t be able to take up the needed micronutrients from the neutralized soil. Also, blueberries plants rely on mychorrhizal associations with fungi to take up nutrients. Even though we had inoculated the young plants with mycorrhizae, it may not have had adequate time to colonize the new roots, so a combination of hard water and possibly the lack of established mycorrhizae stressed the plants and most of them died. We were in the process of collecting acidic rainwater, and experimenting with acidifying our well water when we stumbled onto an easier method of propagation, simple plant division. The wild blueberries propagate mainly by layering, and most of the roots are in the moss layer above the mineral soil. By going around the perimeter of a wild blueberry plant and pulling up on the branches, one can fairly easily expose a portion of a branch with roots on it. These rooted branches can be pruned so they don’t have too much top growth for the surviving root system, and the plant division can be potted up and treated just like the rooted cuttings. Over the summers of 2013 and 2014, we identified about 50 superior mother plants in the wild and by plant division have approximately 500 potted plants ready to plant on our farms during the summer of 2016.

Introduction

The bog blueberry, Vaccinium uliginosum, grows across millions of acres of the circumpolar north. It has been a staple food for indigenous people throughout history. Most northern people prefer the flavor of the bog blueberry to domestic blueberries, but commercial varieties of V. uliginosum have never been developed in North America. Most of Alaska is too far north for the domesticated North American high bush, half high, and low bush blueberries (V. corymbosum, V. angustifolium, and hybrids) to survive. Also, recent scientific studies have shown that Alaskan bog blueberries contain concentrations of antioxidants approximately 10 times higher than domestic blueberries. The bog blueberry remains a choice berry for wild berry pickers in Alaska and the demand far exceeds the supply. However, the plants are short, and the labor of picking the berries makes them too expensive to market commercially. When picking wild blueberries in Interior Alaska, we find that there is a tremendous variability in berry size, shape, flavor, bush height, and other characteristics. The plants are all in the species of Vaccinium uliginosum. We don’t know how much of this variability is due to genetic differences, and how much is due to the age of the plant, microclimate or other site conditions. Our goal has been to collect wild blueberry plants that exhibit desirable characteristics and move them to our farms where they can be grown under uniform conditions so we can determine if those desirable characteristics are true differences, or just responses to favorable site conditions. This project was an effort to collect superior bog blueberry plants and move them to agricultural fields where they could be evaluated for domestication. It also provided an opportunity to involve the public and provided information on bog blueberry selection, propagation and production to potential growers.

Project Objectives:

Obj. 1.  Select 50 superior bog blueberry plants from diverse locations in Interior Alaska, collect 30 cuttings from each plant, and record the site characteristics and plant characteristics that make each plant desirable for propagation.

Obj. 2.  Root and care for the cuttings; i.e. root 1500 cuttings in a misting chamber, plant 1000 of the best rooted cuttings (20 from each mother plant) in 3 1/2 inch pots, allow them to become dormant, overwinter them, start the plants off in a greenhouse the next spring, and move them outside in mid summer to harden them off.

Obj. 3.  Plant 10 plants from each mother plant (500 for each farm) in rows in agricultural fields where they can be evaluated for desirable characteristics for domestication and mechanical harvesting.

Obj. 4. Share information about bog blueberries, their selection, propagation, and management with other berry growers by: a) giving a presentation to the Alaska Pioneer Fruit Growers Association in Anchorage; b) giving a presentation at the SARE Conference in Fairbanks; and c) holding an informal field day in cooperation with the Cooperative Extension Service at Papa’s Greenhouse.

Cooperators

Click linked name(s) to expand
  • Dr. Patricia Holloway

Research

Materials and methods:

Materials:

Horticultural vermiculite (Sta-Green 6 cubic feet)

Perlite (Supreme 16 cubic feet)

Sphagnum moss (Greensmix 16 cubic feet)

ProMix (16 cubic feet)

Shredded Peat (Great North West Landscaping 80 cubic yards)

Rooting compound (0.3% indole-3 butyric acid)

Fogging tips for misting system (4 each)

Timers for misting system (2 each)

3 1/2-inch square pots (1000)

1-gallon pots (600)

Landscape fabric (4 feet by 2000 feet)

Emitters and 18-inch drip tubes (1000 each)

Drip irrigation line (3/4 inch by 2000 feet)

Soil pH meter (Hanna Instruments)

 

Contractual Services:

Leased greenhouse space with electricity, lighting, heat, misting system etc. (Papa’s Greenhouse 2 summers)

Leased van for transportation and camping overnight while collecting blueberry plants (Papa’s Greenhouse 900 miles)

Registration fee for SARE Conference in Fairbanks

Travel to Anchorage to Alaska Pioneer Fruit Growers Association

 

Methods:

We drove to numerous sites within 150 miles of Fairbanks and collected berries and plant materials from superior blueberry plants. We brought the plant materials back to Knight Farms and prepared cuttings for rooting in the greenhouse. We rooted the blueberry cuttings in Papa’s Greenhouse at North Pole, Alaska, potted them up in a mix of 3/4 ProMix and 1/4 sphagnum moss to which we added a little compost and a little soil with native mycorrhizae from under wild blueberry bushes. We overwintered the potted plants outside under the snow. We purchased 80 cubic yards of peat from a local peat company and had half of it delivered to Papa’s Greenhouse and half of it delivered to Knight Farms. We started preparing sites on both farms for planting out the final plant selections using 4 inches of peat rototilled into the soil for acidity and improved water holding capacity. The next summer, before we took the plants to the field, we lost many of our plant cuttings to micronutrient deficiencies. We realized that our irrigation water quality was bad (contained too much lime), and our newly rooted cuttings may not have gotten sufficiently colonized with mycorrhizae. On the second year, we changed our method of propagation to plant division and collected numerous more plants with roots intact. About 500 of those plants are currently overwintering and should be planted on our prepared fields in August of 2016.

Research results and discussion:

This project has attracted a lot of attention throughout Interior Alaska. Prior to this project, the general public opinion in Alaska was that Vaccinium uliginosum could not be successfully moved from the wild to a garden or field. Several people had reported that they had dug up blueberries from the wild and moved them home only to have them die or possibly to remain alive but never produce any significant berries. About 10 years ago, I was discussing this public opinion with Dr. Danny Barney, who at that time was a blueberry breeder working for the Cooperative Extension Service at Sandpoint, Idaho. He explained that Vaccinium uliginosum plants must be seven or eight years old before they start producing significant berries. They often produce heavily for five or six years then their production starts to taper off even though they may continue to produce for 20 or more years. The public often finds a wild blueberry plant that is producing very well. It is probably 10 or 12 years old. They dig it up, bring it home and plant it. It is an old plant, it will undergo a couple of years of transplant shock, and the new soil may not be acidic enough or contain the correct fertility for the plant. Thus, the plant dies or never produces like it did in the wild. Dr. Barney recommended that one look around the perimeter of a wild blueberry bush and select a juvenile portion of the plant for propagation rather than the main portion of the plant that is currently producing berries. That is what we have done, and the public is generally amazed that we are successfully growing blueberries that we have brought in from the wild.

 

We have made some mistakes and lost some plants, but the greatest impact of this study has been the change of public opinion about the possibility of growing native blueberries. Master Gardeners and greenhouse managers are currently seeking local blueberries that they can grow or sell. It will take a few years to identify the best genetic materials, but the likelihood of a commercial blueberry industry developing in Alaska is much greater due to this SARE project.

Participation Summary

Educational & Outreach Activities

Participation Summary:

Education/outreach description:

Guest speaker at the Greater Fairbanks Chamber of Commerce about SARE Grant and Alaska Blueberry Propagation (attendance 85).

 

Gave a SARE project update and progress report to the Cooperative Extension meeting of the Interior Alaska Small Fruit and Berry Growers (attendance 16).

 

Guest speaker at the Interior Alaska Chapter of the Alaska Native Plant Society about SARE Grant and Alaska Blueberry Propagation (attendance 14).

 

Guest speaker at SARE Conference in Fairbanks regarding SARE Grant about Bog Blueberry Propagation Project and led a discussion group about small fruits and berries (attendance 164).

 

Guest speaker at Fairbanks Farm Bureau Annual Meeting about SARE project on Wild Blueberry Selection and Propagation (attendance 36).

 

Guest speaker at two Master Gardener classes about berries for home gardens (attendance 22 & 25).

 

Put up photos and public display at SARE Conference and Farm Bureau Meeting

Held public Field Day at Papa’s Greenhouse to show Blueberry Propagation Methods

 

Took six members of Alaska Pioneer Fruit Growers Association on blueberry tour at Papa’s Greenhouse, then helped them collect plant materials from wild blueberry stands in the Fairbanks area.

 

Met with managers of Ann’s Greenhouse and Holm Town Nursery about selection, propagation, and potential markets for native blueberry plants.

 

Met with numerous individuals about how to select for superior blueberries, how to propagate the plants, how to prepare the soil, and how not to kill their plants with hard irrigation water.

Project Outcomes

Project outcomes:

Our first objective was to seek out traditional blueberry picking areas in Interior Alaska and to select at least 50 superior mother plants based on their berry size, productivity, plant height, etc. We reached that milestone in 2013.

 

Our second objective was to collect at least 30 cuttings from each of those mother plants and root them in a misting chamber, pot them up, overwinter them, and get them ready to plant out on two farms. We accomplished this task up to a certain point, but never really reached the milestone as defined. Sometime during the rooting process, we lost heat from one of the heating mats in the bottom of our rooting chamber. Therefore, only about half of our cuttings grew sufficient roots to pot up in the fall. Then, the following spring, the cuttings leafed out and slowly began to turn red and die. We discovered that it was a micronutrient problem in the young plants and that the pH of our potting mix had risen from about 4.5 to approximately 7. We traced the problem to the well water that we were using to irrigate the plants in the greenhouse. It contained a lot of lime and had a pH of 7.3. Since our pots were small, apparently the irrigation water overpowered the acidity in the potting mix. We had previously used this same water to irrigate blueberries in the garden without any problems. However, the plants in the garden had a lot more soil to explore, the plants in the garden received a lot of acidic moisture from rain and snow, and the plants in the garden had mycorrhizal associations established with their roots which would help them take up iron and other micronutrients. We had inoculated the newly rooted cuttings with mycorrhizae, but the new roots may not have been sufficiently colonized, and the small plants were unable to take up the micronutrients.

 

During the late summer of 2013, Papa had dug up a couple of blueberry plants and divided each of them into several plants, each with at least two good roots. He pruned back the top growth to match the roots on each plant division and planted them into acidic soil similar to what was used for the blueberry cuttings. These plants were planted into larger pots (1-gallon) and left outside where they received rainwater and snow. In the summer of 2014 when the rooted cuttings were dying, the plant divisions were thriving. Thus, during the summer of 2014 and 2015, we returned to the mother plants and collected plant divisions and currently have approximately 500 potted plants ready to plant out on the farms in 2016 (objective 2 accomplished).

 

Objective 3 was to divide the blueberry plants into two equal batches and plant some from each mother plant onto each of two farms for further evaluation. We expect to finish this objective next summer.

 

Objective 4 was to involve the public and share information with potential blueberry growers. We accomplished that goal as is explained under Outreach.

Recommendations:

Potential Contributions

Several farmers have expressed an interest in growing Alaska’s wild blueberries commercially. Several farmers and local nurserymen have attended our field days and public presentations and have asked questions regarding propagating and growing wild blueberries. However, when the subjects arise about maintaining acidity in the field soils, ensuring that irrigation water is acidic, and what type of harvester will be needed, potential growers back off and wait for someone else to provide the first demonstration. Local microbreweries, wineries, and ice cream manufacturers advertise for local berries but the prices offered have not yet been high enough to entice venturesome growers to take the first step in establishing production fields.

 

The market for bog blueberries is speculative. Alaskan blueberries will probably never compete with store-bought blueberries on a dollar for dollar basis. However, Alaskan blueberries are superior to those in stores, both in flavor and in chemical composition. Numerous journal articles have documented the high levels of antioxidants and pharmaceuticals found in northern Vaccinium species. Some of these same chemicals are found in commercial blueberries, but at much lower concentrations. The problem is that no one specific chemical has been cited as being the most important, and no specific dose has been determined to meet human needs. Several companies are currently marketing pills, powders, and candies that contain a few drops of bog blueberry extract and extoll its almost miraculous properties in preventing human disease, but those same companies expect to purchase bog blueberries at a cheap price competitive with other types of blueberries found in stores. At some time in the future, the market for bog blueberries could explode if a market develops for dehydrated blueberries, extracted chemicals, or other products for a specific chemical. In the meantime, the current market is for fresh, good tasting blueberries for home use and for the tourist industry. Most fresh berries are used as toppings on cereal, yogurt and ice cream. Bed-and-breakfasts like to serve Alaskan blueberries in muffins, pancakes, and breads. Commercial manufacturers of ice cream, wine, and micro-brews like to use local blueberries for specialty products. There is also a constant demand for blueberry jams, jellies, and syrups. The market for fresh or frozen bog blueberries has not been adequately tested because of the labor involved in harvesting the berries. There are no berries for sale, so nobody knows what consumers are willing to pay.

Future Recommendations

Need studies on amending local soils for blueberry production and maintaining soil fertility and soil acidity in subarctic blueberry fields.

 

Need studies on harvest equipment design and plant spacing patterns for Vaccinium uliginosum grown for commercial production.

 

Need studies on marketing fresh and dried Alaskan blueberries and showing their superior characteristics to domestic blueberries found in the stores.

Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture or SARE.