While Music has shown to be an excellent cultivar for growing conditions in Ontario, there may be other cultivars that perform just as well. Whether that is an increase in yield per acre, average bulb size or the ability to store into the spring. Additionally, consumers are becoming more aware of the different tastes of garlic and are willing to pay more for a spicy flavour.

Summary

Most agronomic information about garlic found online is from areas with different climatic conditions to Ontario and most information is written in a language other than English. Much of the production research in Ontario to date has been conducted by John Zandstra out of the University of Guelph – Ridgetown Campus over the last two decades. Trials conducted in conjunction with the Garlic Growers Association of Ontario have identified ideal planting densities, spacings, methods for bulbil production as well as scaping for the cultivar Music, but these production practices may not hold true for all of cultivars discussed below

Therefore, it is important to grow cultivars locally to confirm that they yield and store as well as they did in the previous location. Most cultivars that perform well in France, Spain, Brazil or China do not perform as well in Ontario and may take several field seasons to acclimatize to the climate and daylength. In general, softneck cultivars grow better in warmer climates and do not respond to changes in daylength compared to hardneck cultivars. Hardneck cultivars are more suited to temperate climates, such as Ontario, that have a winter vernalization period and greater changes in daylength throughout the year.

This trial was meant to demonstrate the differences in cultivars from the same planting stock but grown in different conditions and soil types. Last year 22 garlic cultivars (16 hardneck, 6 softneck) were planted in three locations in Southwestern Ontario in mid-October 2018.  Before examining the data, it is important to note that the first two reps at the Gorrie location experienced flooding in the early spring and had a poor emergence rate. The plants that survived the unfavourable conditions at Gorrie are included for interest, as we found a few cultivars performed well regardless of the flooding.

Full Report

EVALUATION OF GARLIC CULTIVARS FOR ONTARIO GROWING CONDITIONS IN THE 2018-2019 FIELD SEASON

MATERIALS

Garlic (Allium sativum L.), cvs. Music, Newfoundland, Ivan, Portugal 1 Azores, Mount Hood, Yugoslavian Red, Georgian Fire, Russian Red, Red Russian, Kranagasger Red, Duganski MPS, Duganski White, Purple Glazer, Guelph, Ukraine, Polish White, Sicilian Gold, Transylvanian, Nootka Rose, Saba Gold, Messadore, Thermadore

OBJECTIVES

Compare yield, fresh and dry bulb weights of 22 garlic cultivars.

METHODS

Garlic cloves of 22 cultivars previously grown in Ontario were seeded by hand in three locations; Gorrie in Huron clay loam on 13 October, 2018, Dashwood in Huron clay loam on 16 October, 2018, and Ridgetown College in Wattford loamy sand 30 October, 2018. Hardneck cultivars include Music, Newfoundland, Ivan, Portugal 1 Azores, Mount Hood, Yugoslavian Red, Georgian Fire, Russian Red, Red Russian MPS, Kranagasger Red, Duganski MPS, Duganski White, Purple Glazer, Guelph, Ukraine, and Polish White. Softneck cultivars include, Sicilian Gold, Transylvanian, Nootka Rose, Saba Gold, Messadore and Thermadore. The average clove sizes for each cultivar were equal for each planting location. Cultivars were planted in a randomized complete block design with four replicate rows. Each row had 10 cloves of garlic planted per row at a depth of two inches. Planting densities varied based on location with ~170k plants per acre in Ridgetown and ~65k plants per acre in Dashwood and Gorrie. Black plastic was used as weed control at the Ridgetown location while plants were hand weeded as necessary at the other two locations. No plants received irrigation throughout the season. Scape stage was quantified 19 June in Gorrie and 26 June for Dashwood and Ridgetown by measuring the direction of the spathe in relation to the scape rising from the plant using a 0–2 scale where 0 = no scape observed, 1 = one full loop and 2 = two full loops. The scape stage at 21 June reflects when the scapes would most likely be harvested and may not reflect the final scape stage.The trial was harvested 24 July in Ridgetown, 25 July in Gorrie and 26 July in Dashwood. At harvest, bulb basal plates were rated for damage by assessing the percentage of basal plate missing using a 0–4 rating scale: where 0 = no damage; 1 = 1 – 24% basal plate missing; 2 = 25 – 50% basal plate missing; 3 = > 50% basal plate missing and 4 = completely desiccated bulb. Bulbs were cured in mesh bags within a pallet box in a forced air dryer over an 11 day period from 26 July to 6 August. Dry weights were collected on 21 August. Data were analyzed using SAS version 9.3 (SAS Institute, Cary NC). Means were separated using Tukey-Kramer multiple mean comparison test (P = 0.05). 

RESULTS

Flooding at the Gorrie location caused poor emergence for the first and second repetition. The plants that survived the unfavourable conditions at Gorrie are included for interest, as a few cultivars performed well despite the flooding. Height assessment on 15 May, found Polish White, Ukraine, Transylvanian, Guelph, Portugal 1 Azores, Purple Glazer, Mount Hood, Duganski MPS and Georgian Fire to be the tallest at the Dashwood location while Polish White, Mount Hood, Ukraine, Music and Portugal 1 Azores were the tallest at Ridgetown (Table 1, 2). Most of the hardneck cultivars had more leaves per plant than the softneck cultivars at the 15 May assessment at both locations with Transylvanian being the best performing softneck cultivar. Scape assessment showed a wide variation in the progression of the scape and no cultivars showed a double loop, as was seen in the 2017–2018 trial with Ivan. The strong bolting cultivars showed scape development as expected and no scapes were observed in the softneck cultivars. No cultivars displayed a straight scape and the umbel capsule/topset characteristics were not assessed. At harvest, the plant fresh weight found Portugal 1 Azores, Ukraine, Polish White, Duganski MPS, Red Russian MPS, Kranagasger Red and Mount hood to be the heaviest at the Dashwood location with Polish White, Duganski MPS, Red Russian MPS, Ukraine and Portugal 1 Azores weighing the most at Ridgetown. The marketable dry weight of Polish white, Portugal 1 Azores, Ukraine, Guelph, Transylvanian, Duganski MPS and Mount Hood showed no significant difference from Music at Dashwood. At Ridgetown, the marketable dry weights of Polish White, Duganski MPS, Ukraine, Transylvanian, and Red Russian MPS were significantly higher than Music. Transylvanian was consistently the top performer of the softneck cultivars in fresh and dry weights at both locations. When comparing the fresh bulb weight to the clove weight at planting to get a multiplication value/rate (clove wt at planting x bulb to clove ratio = fresh bulb wt), there were not many significant differences between cultivars at the Ridgetown location, while at Dashwood Sicilian Gold, Nootka Rose, Russian Red, Purple Glazier, Saba Gold, Transylvanian, Portugal 1 Azores all performed significantly better; however the average clove planting size of Russian Red, Sicilian Gold and Nootka rose were small to start. At the Dashwood location, the largest bulbs when it came to circumference were from Duganski White & MPS, Polish White, Ukraine, Red Russian, Portugal 1 Azoles, Transylvanian, Kranagasger Red, Sicilian Gold, Mount Hood, Guelph, Purple Glazer, and Music. The greatest circumferences at the Ridgetown location were Duganski MPS, Red Russian MPS, Polish White, Kranagasger Red, Transylvanian and Ukraine. No significant differences were observed in basal plate rot at harvest. Cultivars were not tested for bulb and stem nematode or virus load prior to planting or after harvest.

CONCLUSIONS

Most cultivars that recorded a taller height and an increase in number of leaves at the 15 May assessment also had the largest bulb weight at harvest. Many of the cultivars trialed performed better than the predominately grown cultivar in Ontario – Music – and most had a higher rate of multiplication from the time of planting to the final average bulb weight. The majority of the cultivars highlighted in this report will be assessed again in the 2019–2020 field season in Ridgetown and Dashwood. Further research should explore the storability of the various cultivars to determine if storage duration can be extended relative to Music.

In kind contributions were made by Simon de Boer of Langside Farms, Bob Romaniak of Brant County Garlic, Dean, Martin, and Teresa Van Raay of Van Raay Farms, Julie Fleischauer of Golden Acres Farm, Nathan Teetzel of G & L Farms, Alf Semenuk of Pioneer Nursery, Tony McNamara of Acadian Shamrock Farm, Daniel Hoffmann of The Cutting Veg and Norm de Groot of Aromatic Acres. Thank you to Josh Mosiondz, Victoria Snyder, Emily Pennington, Owen Hebb, Ashleigh Ahrens, Cora Loucks and Angela Tiessen for their help throughout the trial as well as the support provided by the Garlic Grower Association of Ontario.