July 10, 2020
In this bulletin:
- Crop & pest update
- Spotted wing drosophila
- What’s Growing ON? Podcast
Strawberry harvest is winding down. Raspberry and blueberry harvest has begun in southern Ontario. Hot, dry weather continues across the province.
The June-bearing strawberry harvest is slowing down as growers continue to harvest Valley Sunset and begin to pick Malwina. Renovation has started in southern Ontario on early varieties. Many pick-your-own operations are done for the season or finishing this weekend- despite the hot weather growers had a great season of PYO. Looking forward to this interest continuing into other berry crops!
New plantings are variable at this point. Make sure your new plantings are getting enough water.
Day-neutrals are beginning to bloom for the next crop.
Hot & dry weather continues, and irrigation may be needed as renovation begins. Rebecca Shortt has an article on our blog on How to Ensure You Are Getting the Most Crop Per Drop (URL: https://onfruit.ca/2020/06/30/how-to-ensure-you-are-getting-the-most-crop-per-drop/).
Insects: Spotted wing drosophila is active in many areas. After harvest renovate and mow the plants as soon as possible to reduce SWD populations building up if there are other berry crops or later strawberry varieties on the farm. See more details on SWD management below.
Other insect activity has been fairly low. Potato leafhoppers can be found in day-neutrals. Keep monitoring for aphids and cyclamen mites in June bearing fields and tarnished plant bugs in day neutrals.
Tarnished Plant Bug: monitor day neutral strawberries for TPB as they begin to bloom. There is some evidence that Assail will provide some post-infestation control of small SWD eggs and larvae, so Assail could be a good choice if a TPB insecticide is needed and ripe fruit is present. Rimon and Beleaf are good options for TPB as they are easy on beneficial insects but they do not provide much, if any, activity on SWD.
Cyclamen mites: Consider cyclamen mite management as you plan for renovation. If you find mites or symptoms spray that entire variety or block. Check new fields as well – cyclamen mite damage has been found in first year fruiting fields. Mites may be difficult to find where there isn’t much new, succulent growth, but the population will likely build up again in August or September.
Renovation is a good time for cyclamen mite control. If a miticide is needed after renovation:
- After renovation Vegol crop oil can be applied in a high water volume to ensure thorough coverage.
- Agri-mek is registered for Two-spotted spider mite (TSSM) post-harvest. If you are applying agri-mek for TSSM you will achieve some efficacy on cyclamen mite.
- Apply Agri-mek once there is new growth after mowing, which could be approximately 5 days after mowing. Apply Agri-mek at 225 mL/ha in 750-1000L water /ha, with a non-ionic surfactant at .1-.5%. Monitor the water pH.
- Slow down and get thorough coverage of the plants and crowns.
- Apply Agri-mek under slow-drying conditions to improve uptake into the leaves.
- Do not apply sinbar after applying Agri-mek. Wait 5-7 days after Agri-mek before applying sinbar.
- Avoid spreading cyclamen mites to new fields; work in new fields before moving to old, infested fields.
Disease: Angular leaf spot (ALS) and powdery mildew were reported this week. Check new fields as well as fruiting fields for ALS and powdery mildew.
Fungicides are being applied to day-neutrals as bloom begins for anthracnose, powdery mildew and botrytis. Although it has been dry a single rain can cause an anthracnose outbreak- Use products that will control botrytis and anthracnose.
Switch (9+12), Diplomat (19), Pristine (7+11), Cabrio (11), Luna Sensation (7+11) & Quadris Top (11+3) are registered for control of anthracnose. Anthracnose resistance to group 11s has been identified in Ontario. Rotate the use of group 11s with different groups, and tank mix with a group M fungicide for botrytis control to avoid developing resistance. Check out these Anthracnose Management Suggestions 2020
Renovation is beginning; Renovate as soon as harvest is complete. Do not wait for late varieties to be harvested to renovate earlier blocks. This will help manage SWD- mowing strawberries will help fruit to dry up and make it less attractive to SWD.
Assess your fields before renovation for weed pressure to determine if herbicides are needed and if so which herbicides to use. Broadleaf herbicides need to be applied 5-7 days before mowing. Avoid applying herbicides if temperatures are above 25C. Refer to the Publication 75B Guide to Weed Control Hort Crops for herbicide options. The earlier you can apply the herbicide (if necessary) and mow your strawberries the better for SWD management. After renovation do not apply sinbar in close sequence to grass herbicides, Lontrel or 2,4-D (10-14 days). Herbicides such as Sinbar and Devrinol as pre-emerge products require 1-2 cm rain or irrigation following application. Do not apply sinbar after applying Agri-mek. Wait 5-7 days after Agri-mek before applying sinbar.
Fertilizer: The best time to apply nitrogen in established fields is at renovation. After you mow the foliage, apply 50 kg N per ha.
Irrigation: strawberries need adequate moisture after renovation for plant growth and runner development. If possible, irrigating will help at renovation, or wait until a rain to mow. If plants are under water stress consider mowing high.
Raspberry harvest and pick-your-own has begun from southern to eastern Ontario this week. See the SWD update below- it is likely time to start spraying in summer-fruiting raspberries depending on your location.
Blueberry harvest has begun in southern Ontario and are ripening in central Ontario. Blueberry harvest will begin will begin in the next 1-2 weeks in eastern Ontario . The crop continues to look good.
Spotted wing drosophila:
Spotted wing drosophila (SWD) has been identified in all areas where we are monitoring ( Essex, Kent, Elgin, Norfolk, Brant, Niagara, Oxford, Halton, Durham and Northumberland) many of these sites have found SWD for 2-3 weeks. Although the weather has been hot and dry SWD is active and pressure could increase quickly. Growers need to start managing for SWD now where ripe fruit is present, including in late June-bearing strawberry varieties, summer-fruiting raspberries, and blueberries. SWD Registrations June 2020 final
Do not count on sprays alone:
- Apply an insecticide every 5-7 days.
- Reapply after ½ inch of rain.
- Use products from different groups.
- Spray in the morning (6-10am) or in the evening (6-10 pm) when SWD is active.
- Do not spray in temperatures above 25C.
- Pyrethroid insecticides (Mako, Up-Cyde) will not work well in hot weather and will cause an increase in mites. Save these products for later when weather cools off and mite pressure is low.
- Calibrate your sprayer. Slow down & spray every row.
- Keep weeds and vegetation mowed or otherwise controlled in and around the field.
- Control wild hosts (cut below the fruiting zone).
- Keep alleys clean- either remove unmarketable fruit or crush it in the alleys. Destroy unmarketable fruit removed from the field.
- Pick regularly (every other day) and clean!
- Cool fruit as soon as possible after harvest and keep it cool through all stages of marketing (below 2C).
Check the Onfruit.ca blog for full details on counts which will be updated weekly and a list of registered products.
What’s growing ON? Podcast:
Check out the new podcast What’s Growing On? The latest episode covers weather stations and strawberry anthracnose management. This podcast also includes episodes from other crop specialists, including vegetables, apples, and tender fruit. All episodes can be found under the Podcast tab on the blog homepage or at onfruit.ca/podcast.
You can also search for episodes on your favourite podcast app including Apple Podcasts, Spotify and Google Podcasts.