research On Our Farm

We’ve performed several on-farm research projects to develop better organic farming techniques.  This page is for other farmers who would like to learn about what we have done.

Bloom Thinning for Organic Apples


It is important to manage cropload in apples in order to increase fruit quality and size and to reduce biennial bearing.  Thinning is challenging for organic orchardists.  We are evaluating the pollen tube growth model and sprays of Regalia and oil as a technique for bloom thinning. 

Read a detailed report of our results.

Watch a video report of the project.

Trellising Currants and Gooseberries


We are currently evaluating the cordon trellis method for growing currants and gooseberries.  We are comparing this trellising method, which is popular in Europe, with the standard North American method of growing freestanding, untrellised bushes.  Cordon trellising is said to speed harvest, improve fruit size, and reduce disease.  We are measuring material costs, labor time, yield, and fruit size for trellised and untrellised plants and we will report final results here.

View a preliminary report of our results from the first three growing seasons.  In 2020, we established trellised and untrellised plantings.  After three growing seasons, the trellised plants had substantially higher materials costs and labor.  Effects of trellising on yield were complex and varied.

Anthracnose Leaf Spot In Gooseberries


Anthracnose leaf spot causes severe leaf spotting and defoliation of gooseberries in the Upper Midwest.  With funding from a USDA-SARE Farmer Rancher grant, we evaluated potential methods for controlling this devastating disease on an organic farm.  There were huge differences in disease resistance among the four varieties we studied, with Hinnomaki Red most resistant, Tixia most susceptible, and Captivator and Black Velvet intermediate.  Regular sprays of Cueva (copper soap) with Double Nickel (Bacillus amyloliquefaciens) significantly reduced disease.  Regalia (Reynoutria sachalinensis extract) sprays provided less control, and Carb-o-nator (Potassium bicarbonate) had no effect on disease.  Compared to freestanding bushes, the cordon trellis method reduced disease by a modest amount. 

View a full report of our results.

Watch a video highlighting key project results.

Organic Apple Production In High Tunnels

HH6 June 10 2

With funding from a USDA-SARE Farmer Rancher grant, we evaluated the feasibility of growing organic apples in high tunnels. The trees grew vigorously and fruited quickly. As expected, most diseases were rare or absent in the tunnels; but insect damage occurred at broadly similar levels to the damage in outdoor orchards. Sunburn, soft flesh, and off-flavors were common in the fruit of many varieties, presumably because of the hot environment within the tunnels. Overall, we concluded that high tunnel cultivation of organic apples is difficult to justify because of the costs of high tunnel construction and maintenance, heat-related fruit defects, and the need for sprays to control insect damage. If high tunnel cultivation is feasible, it seems essential to focus on heat-adapted, high-yielding varieties, such as Suncrisp in our study. Read our report with a detailed description of our growing methods, observations, expenses, and yields.

Control of Canada Thistle in Mulched Organic Orchards


With funding from a USDA-SARE Farmer Rancher grant, we compared several methods of eliminating dense Canada thistle patches growing in bark mulch in our organic apple orchard. Any method of repeatedly killing the thistle shoots on three week intervals eliminated the weed within two growing seasons. Of the four methods we applied, cutting shoots with a gas powered string trimmer and cutting them with a diamond hoe were least costly; spraying an organic herbicide was expensive because of the cost of spray, and hand-pulling shoots was expensive because of the labor time required. Applying a layer of cardboard mulch underneath the bark mulch reduced subsequent weeding time and hastened the decline in thistle populations, but was not cost effective because the time required to apply the mulch outweighed the subsequent time savings.

Read a full report of the results.

Branching In Nursery Apple Trees

With funding from a USDA-SARE Farmer Rancher grant, we compared organic methods of promoting branching in nursery apple trees raised in a high tunnel.  Manually removing young leaves near the growing point of the tree increased branching slightly, and spraying trees with a seaweed extract high in cytokinins reduced branching slightly.  In addition, there were strong differences between varieties in branching and there was much variation among individual trees in both height and branching.  The cost in materials and labor for raising a tree in this system was approximately $11.95-$12.08, excluding overhead costs and costs of facilities and equipment; the different treatments to promote branching had minor effects on the overall cost of raising a tree.

Read the full research report.

Maypops, A New Fruit Crop?


With funding from a USDA-SARE Farmer Rancher grant, we evaluated maypops (a species of passionflower) as a new fruit crop for hoophouses in the upper Midwest. The vines gew vigorously.  There were differences between plant sources in flavor, yield, and growth pattern, suggesting that breeding and selection might develop improved varieties. Inadequate insect pollination appeared to limit fruitset.  Juice yield was extremely low (about 2.5 quarts of juice from 120 plants) and a much higher yield is needed to justify the costs of growing the plants: about $1400 of supplies and labor was needed to grow these plants. Maypop juice caused stomach sickness to several people, and we could not recommend the fruit.

Read the full research report.

Two Onion Farm
Chris & Juli McGuire
19638 Cottage Inn Road
Belmont, WI 53510
(608) 762-5335 (office)
(608) 726-2550 (cell)

Blue Roof Orchard
Chris & Juli McGuire | 19638 Cottage Inn Road, Belmont, WI 53510 | (608) 762-5335 (office) | (608) 726-2550 (cell)