July 5, 2019 Berry Bulletin July 5
Strawberries: Farms across the province opened up for Pick-Your-Own last weekend in time for Canada Day. Mid-season varieties are beginning to be harvested in southern Ontario and there is a nice crop of June-bearing strawberries coming on. Malwina is still blooming in Southern and Eastern Ontario so there will be June bearing strawberries until the end of July- early August.
Fall-planted day-neutral harvest is wrapping up in southern Ontario, and this year’s spring-planted day-neutrals will be blooming soon.
Insects: Watch for Potato leafhoppers, thrips, winged strawberry aphids, cyclamen mites and two-spotted spider mites this week. The last TPB and aphid sprays during bloom are going on later varieties.
Strawberry Aphids & Virus: High numbers of aphids can be found in fields where an insecticide hasn’t been applied in a few weeks. Aphids need to be controlled when there are more than 15 aphids on 60 leaves-typically every 3-4 weeks. Beleaf, Exirel, Sivanto Prime, Assail, and Vegol Crop Oil have short PHI (0 or 1 day), or plan to include an insecticide after renovation when there is new growth. Exirel will be a good choice if strawberry growers need to spray for aphids and SWD, as Exirel will also control SWD.
Thrips: thrips may be an issue this year in June-bearing strawberries and damage has been found in a few fields. Check late varieties and day-neutrals with bloom and ripening fruit for thrips in the blossoms or under the calyx of ripening fruit. Thrips will cause fruit bronzing and seedy berries. Control may be necessary in June bearing strawberries if there are 5 thrips per bloom. Delegate and Exirel are registered for suppression. Note the precautions when applying Exirel: do not apply or make sequential applications with Group 11 fungicides, captan or maestro, folpan or bravo. Beneficial insects can also be used to manage thrips.
Cyclamen mites: Check all fields (newly planted, first year harvest and older fields) for mite damage before renovation to make a management plan for after renovation. There is limited Agri-mek available so if a spray is needed line up Agri-mek earlier than later. If there is damage the entire field or at least the entire variety should be sprayed. Agri-mek is registered for two-spotted spider(TSSM) mite post-harvest. If you are applying agri-mek for TSSM you will achieve some efficacy on cyclamen mites.
Potato leafhoppers: monitor for leafhoppers in day-neutrals and fall raspberries. Check for curling and yellowing leaves, and confirm PLH by looking at the underside of the leaf for the PLH nymphs. Control may be necessary if there are 1-2 nymphs per leaf.
Disease: Anthracnose and botrytis have been found in June-bearing fields, and powdery mildew is showing up in day-neutral strawberries. Rotate between fungicide groups and include group M products for resistance management.
Blueberries: Green fruit is present and early harvest could begin the second week of July in southern Ontario. Green fruit is present in Eastern Ontario. The crop is looking good across the province.
Insects: Cranberry and cherry fruitworm insecticides may be necessary 10-14 days after an initial application if this pest has been in an issue in the past.
The PHI for Delegate to control SWD on blueberries has been reduced through the minor use program. The PHI is now down to 1 day, which should help manage maintaining insecticide coverage with regular picking.
Raspberries: Green fruit is present and the first ripe berries can be found in southern Ontario. Harvest will begin next week in southern and central Ontario, and continues in the south-west. Fall-bearing raspberry primocanes are looking good.
Insects: Potato leafhoppers can damage new leaves in raspberries, particularly fall-bearing raspberries. Spray before bloom in fall-bearing raspberries if necessary.
Fungicides: the first fungicides are going on raspberries for fruit rots as harvest approaches.
Spotted Wing Drosophila: SWD has been caught in Chatham- Kent, Essex, Elgin, Norfolk, Niagara, Wellington and Halton county. There is sustained catch (2 weeks or more of catches) in Essex and Norfolk. In these areas sprays are necessary if there is ripe fruit present. In other areas where ripe fruit is present SWD numbers will be building up and growers should harvest regularly and remove unmarketable fruit from the field. In all parts of the province insecticides will likely be needed on late strawberry varieties and summer-fruiting raspberries.
Growers can conduct salt water tests or plastic baggie tests to assess presence of larvae in fruit.
Spraying for SWD isn’t necessary until there is ripe fruit present + SWD is active in your area. SWD will not infest unripe berries.
Do not count on sprays alone– use as many of these tools as possible through the season to control SWD:
- Keep your fruit picked regularly and clean!
- Cool fruit immediately after harvest.
- Keep alleys clean- either remove unmarketable fruit or crush it in the alley
- After unmarketable fruit is removed it should be destroyed (disposed of, or leave in plastic bags in the sun).
- Make the environment less favourable to SWD- prune the canopy and manage water to reduce humidity (repair leaking drop lines).
- Calibrate your sprayers now to ensure excellent coverage once you start to spray.
- Pyrethroid insecticides (MAKO) will not work well in hot weather and will cause an increase in mites. Save the use of this product for later – when weather cools off and mite pressure is low
- Renovate strawberries as soon as possible after harvest to prevent SWD from building up in overripe, leftover strawberries.
- Pick early, clean and often. If possible, do not spray late blueberry varieties until they are close to harvest. There are limited options for blueberry growers so if you can leave blocks unsprayed until necessary the more options you will have. Fruit is not susceptible to SWD until it is turning colour.
- The PHI for Delegate on blueberries is down to 1 day.
- More details on SWD management can be found here.
- SWD registrations are posted on our blog here: https://onfruit.ca/2019/06/21/registrations-for-spotted-wing-drosophila-june-2019/
- Check our blog for regular SWD updates and counts
I have a new phone number: call or text my cell phone at 519-410-0624.