June Newsletter

Tuesday, June 4, 2024

Upcoming Events/Perennia Updates


Below is a summary of some of the industry events that are coming up in the next few weeks! The events listed below are primarily hosted by Perennia, and more information on each of them can be found here.
  • TunnelTalk (virtual Series)
    • June 13 - Greenhouse Ventilation w Matthew Kleinhenz
    • July 10 - Implementing Commercially Available Bio-Control Agents
    • August 14 - Expert Panel Discusses Greenhouse Structures
  • David Vantage Pro 2 Weather Station Maintenance Workshop - Murray Siding
    • June 7
  • Understanding Alternative Nutrient Amendments (Virtual Series)
    • June 25 @6:30 pm - Introduction to Nutrient Amendments 
    • July 2 @ 6:30 pm - Management and Considerations with Compost
    • July 9 @ 6:30 pm - Nutrient Amendments and Soil Interactions 

New Service Launched!

The Plant Health Lab is now offering plant parasitic nematode analysis, following a two year study of nematode presence and distribution across Nova Scotia! 


Check out our website for more information about nematodes, sampling, and general submission guidelines.

Weather Updates

Cucumber beetles have been observed across the Northeastern States! Check back to last month's newsletter about management options

Lets take a look at the weather data collected for this year, and how it compares to our historical records. Growing degree days (GDD) are important for anticipating key dates for crop growth stages, as well as pest emergence and flights. Consider some of the most persistent critters on your farm, and when they typically start to show up. Even if we are still early in the season, its a good reminder to revisit those dates, and think about what needs to happen to prepare for them to limit the impact they have on your farm. 

Figure 1. Degree day accumulation as of May 28, 2024. All data are taken from the Environment and Climate Change Canada weather station located at the Kentville Research and Development Centre, provided by Jeff Franklin. 


Table 1. Degree day accumulations as of May 28, 2024. All data are taken from the Environment and Climate Change Canada weather station located at the Kentville Research and Development Centre. Calculations are based on a start date of March 1, and calculated using the single-sine method. Provided by Jeff Franklin.



Seasonal Considerations: Irrigation


In 2021, the focus of Perennia's annual 'Getting Into the Weeds' series was Irrigation. As precipitation levels remain significantly lower than what typically falls through the month of May, it may be worth revisiting the resources available for those who are looking to fine-tune their irrigation systems. 

Ted van der Gulik, President at the Partnership for Water Sustainability in BC, lays the foundation for planning and design of a drip irrigation system, as well as operating and managing it. These session are focused on implementation outdoors, compared to protected production, but the key considerations for either setup are the same. Concepts such as the importance of considering the amount of water 'lost' to the environment are crucial when calculating the maximum system capacity required, and how much water should be applied on a regular basis. Wind, solar radiation, temperature and relative humidity impact evapotranspiration, which is water lost from the soil surface. The use of plastic mulch, or growing a crop in a container that quickly becomes shaded by the canopy overhead, significantly reduces the amount of water that is lost from the rootzone through evapotranspiration.

Lets consider vegetables that are not mulched in raised beds, and are not grown in a container. Farmwest's Evapotranspiration calculator is a great tool to estimate how much water is lost from the soil through normal environmental conditions. Adjustments can be made seasonally to figure out how much is estimated to be lost different times of the year, however for the most protective strategy, choosing a date range of about a week where evapotranspiration is at its peak (ex. August) allows for you to establish your system at maximum capacity, and scale back when it is not needed. 
  •     Looking to maximize the use of this tool? Check the peak dates over a few years to establish a more reliable value. It's been a wild few years, and we don't want to make assumptions based on one scenario!
Check out the source material on Perennia's Youtube channel for an in-depth refresher!

Production Tidbits: Tank Mixing Made Easy:

As we move towards peak spraying season, growers should be reminded that many tank-mix compatibility problems can be avoided by adhering to the proper tank mix order. The WALES method has been put together to help remind folks of the ideal mixing order. Prior to creating any complex mixes, it is recommended to perform a small-scale test known as a jar test to assess chemical compatibility. This is a good time to remember that the sprayer should be thoroughly cleaned out between uses so that residues from previous applications do not interfere with mixability and application. 

By following the Wales method below growers can generally, mix products in the tank without incident. 

W

  • fill the tank about ½ full with WATER and start the agitation
  • add WATER CONDITIONERS at this time, if needed, for hard water or pH adjustment
  • add WATER SOLUBLE BAGS (WSB) to the clean water in the tank.  Allow the bags to completely dissolve before adding any other products
  • add WETTABLE POWDERS (WP)
  • add DRY FLOWABLES (DF)
  • add SOLUBLE GRANULE (SG)
  • add WATER DISPERSIBLE GRANULES (WDG)

These products may have to be pre dissolved or slowly added to the tank so that they will be dissolved before beginning sucked into the sump, collecting in the filters and plugging the sprayer. Be sure dry products are thoroughly dissolved prior to adding other products. 

A

  • continue AGITATION and allow the dry products to mix entirely to ensure uniform dispersion.

L

  • add LIQUID FLOWABLES like SUSPENSION CONCENTRATED (SC)
  • add LIQUIDS (L)
  • add FLOWABLE liquids(F)

E

  • add EMULSIFIABLE CONCENTRATES (EC) and MICROEMULSION CONCENTRATES (MC)

S

  • Add SOLUTIONS (S) or SOLUBLE LIQUIDS (SL)
  • Add SURFACTANTS and ADJUVANTS
  • Finish by completely filling the spray tank with water and continue to agitate until the spray application is complete. 
  •  Test and adjust water pH if needed before heading to the field

 If boron fertilizers are required in the spray mixture make sure that water soluble bags are completely dissolved before adding the boron fertilizer to the tank. 

For products that quickly degrade at high pH’s be sure to measure the pH of the tank solution before and after mixing is complete as multiple pesticide and fertilizer products can change the overall solution pH. 

There are new rules beginning December 20, 2024, outlining what will be allowable for tank mixes which will be stated on each of the product labels.  To find out more about these new regulations please follow this link.  CLICK HERE. For a summary article on the subject please follow this link: CLICK HERE. 

 Article has been adapted from https://www.syngenta.ca/agronomy/wales-mixing-order.

Feature Pest/Disease: Squash Bug


It will soon be time to start scouting for squash bug, a pest of cucurbits with a particular preference for pumpkins and squash. They feed with their piercing sucking mouth parts and cause leaf necrosis, rapdi plant wilt and scarred fruit. Crop injury from feeding damage can result in reduced yields, delayed plant growth, and poor fruit storability. Squash bugs can also vector bacterial diseases such as angular leaf spot. 


Adults overwinter in plant debris stones, or clods  of soil. They can also be found in nearby wood piles and around building foundations. Adults begin emerging in early to mid-June when they mate and lay bronze coloured eggs on the undersides of leaves. After one or two weeks, the first nymphal instars (immature squash bugs) will emerge. The adults aren't affected by pesticides, and the youngest instars are the must susceptible, so its best to flag a few egg clusters and check back regularly to time your sprays. Be mindful of pollinator presence and only apply spray when bees are not active. 

If you have multiple types of squash in the field, squash bugs seem to prefer pumpkins, blue hubbard, buttercup and kabocah types, so make sure those are getting extra attention during your scouting walks. For more information please refer to Perennia's factsheets on Squash Bug and Cucurbit Angular Leaf Spot

Recent Uploads

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That's all for now! If you have any questions, feel free to reach out to your extension specialist.

Happy growing everyone!

-Talia

Updated 2024 Emergency Use Registrations for Cabbage Maggot in Brassica Crops

Tuesday, May 21, 2024

 

To address the loss of chlorpyrifos (Lorsban, last use date: December 10 2023) in Brassica crops for control of cabbage maggot, emergency use registrations (EUR) were recently approved for Success and Cimegra in Rutabaga and Cimegra in Head and Stem Brassicas (broccoli, Brussel sprouts, cabbage, cabbage (Chinese, Napa), and cauliflower) for cabbage maggot. Application instructions from the EUR labels of each product can be found below. 

 

Success Insecticide

Cimegra

Cimegra

Active ingredient

Spinoad

Broflanilide

Broflanilide

Registration period

May 17, 2024-May 16, 2025

May 21, 2024-May 20, 2025

 May 17, 2024-December 31, 2024

Group

5

30

30

Crop(s)

Rutabaga

Rutabaga

Broccoli, Brussels Sprouts, Cabbage, Cabbage (Chinese, Napa), and Cauliflower

Insect

Cabbage Maggot

Cabbage Maggot

Cabbage Maggot

Application Instructions

Soil drench at the rate of 273 mL/ha to 546 mL/ha (131 g/ha to 262 g/ha a.i,). For 76 cm (30-inch) plant row spacing apply Success at 6 mL to 12 mL per 300 linear metres (1000 linear feet).

Apply 250 mL/ha1 of Cimegra insecticide post-planting as a drench banded spray, 10 cm on each side of the plant targeting the soil and base of plant to control cabbage maggot.  Use a minimum water volume of 1000 L/ha.

Apply 187.5 – 250 mL/ha1 of Cimegra insecticide post-planting as a drench banded spray, 10 cm on each side of the plant targeting the soil and base of plant to control cabbage maggot.  Use a minimum water volume of 1000 L/ha.

Application Timing

Begin applications when adult activity is observed in or near the field.

Apply at peak egg laying and before the build-up of heavy pressure.

Apply at peak egg laying and before the build-up of heavy pressure.

Application Rate

273 - 546 mL/ha

250 ml/ha1

187.5 - 250 ml/ha1

Applications Per Season

2 (Max 1.1L/ha of Success per year)

2 (Max 500ml/ha of Cimegra per year)

2 (Max 500ml/ha of Cimegra per year)

Application Interval

4 days

10 days

10 days

REI

12 hr

12 hr

12 hr

PHI

3 days

40 days

1 day

1 1.9 mL/100 m of row for 76 cm (30”) row spacing.  For a different row spacing, adjust the product rate using the following equation: (row spacing (cm) / 90) x 2.3 mL = mL per 100 m of row.

To reiterate, Success can ONLY be used on Rutabaga for Cabbage maggot. Cimegra has been approved for use in both Rutabaga and Head and Stem Brassicas (broccoli, Brussel sprouts, cabbage, cabbage (Chinese, Napa), and cauliflower) for cabbage maggot but the application rates are different for each crop type.  Full product labels can be found at the Pest Management Regulatory Agency (PMRA) Pesticide Label Search website, always read product labels before applying pesticides.

Pest Update: Cabbage Maggot

Thursday, May 16, 2024

 

With the warm weather finally arriving, it's important to pay attention to when insect pests will become active so that control measures can be implemented. Cabbage maggot (Delia radicum) is a particular challenge in brassica crop production. It overwinters in the pupal stage, emerging in the spring, usually coinciding with the bloom of yellow rocket and serviceberry. From a growing degree day perspective, emergence begins around 161 Growing Degree Days (GDD) at a base of 4°C, with peak flight occurring around 250 GDD for the first generation of cabbage maggot. As of Thursday May 16, 2024, 172 GDD (base 4°C) have accumulated in Brooklyn Corner. If you would like to check how many GDD have accumulated in your area go to Perennia’s Farm Data Tools website. Once there, you can make a free account and access the Farm Weather tool. From the Farm Weather tool map, select a station close to you, which will bring up the GDD calculator as well as current weather condition at that station.

Cabbage maggot feeding on roots. 
Other Delia species, Delia platura (seedcorn maggot), Delia antigua (onion maggot) and Delia florilega (bean seed maggot) are also on the move in the Valley. Once the first generation of adults has emerged in the spring, they take flight and lay their eggs. It is important to know when peak flight is taking place so that you have the opportunity to alter planting times or deploy control measures, such as insect netting, accordingly.  For scouting purposes, eggs can usually be found small clumps on the soil around the base of your seedlings.


May Newsletter

Friday, May 3, 2024

 Upcoming Events

Below is a summary of some of the industry events that are coming up in the next few weeks! The events listed below are primarily hosted by Perennia, and more information on each of them can be found here.
  • TunnelTalk
    • May 1 - Biological Spray Programs w Sonny Murray
    • June 13 - Greenhouse Ventilation w Matthew Kleinhenz
    • July 10 - Implementing Commercially Available Bio-Control Agents
    • August 14 - Expert Panel Discusses Greenhouse Structures
  • David Vantage Pro 2 Weather Station Maintenance Workshop - Cape John
    • Join us and learn how to properly care for your Davis Vantage Pro 2 weather station! During this in-person workshop, we’ll discuss the Davis recommended annual maintenance steps, and some common trouble shooting. We will also cover how to access your station’s data. 
    • Future sessions in Murray Siding, and Kentville
  • In-Person Pesticide Applicator Courses (Advertised by the NSDA)
    • May 14 @ Berwick Legion Hall
    • May 16 @ Truro
    • May 21 @ New Germany 
    • Reach out to your local NSDA Ag Rep for more information!

NSDA Program Updates

Get Growing Program - newly opened!

The Get Growing Program supports small farms in adopting specialized infrastructure and equipment. The program helps with the expansion of local agricultural production for local markets.

Program opening: 18 April 2024
Application deadline: 30 September 2024
Claim deadline: 31 December 2024

Examples of previously-funded projects from Appendix A include:


Weather Updates

Lets take a look at the weather data collected for this year, and how it compares to our historical records! Growing degree days (GDD) are important for anticipating key dates for crop growth stages, as well as pest emergence and flights. Consider some of the most persistent critters on your farm, and when they typically start to show up. Even if we are still early in the season, its a good reminder to revisit those dates, and think about what needs to happen to prepare for them to limit the impact they have on your farm. 


Figure 1. Degree day accumulation as of April 29, 2024. All data are taken from the Environment and Climate Change Canada weather station located at the Kentville Research and Development Centre, provided by Jeff Franklin. 

Table 1. Degree day accumulations as of April 29, 2024. All data are taken from the Environment and Climate Change Canada weather station located at the Kentville Research and Development Centre. Calculations are based on a start date of March 1, and calculated using the single-sine method. Provided by Jeff Franklin.


Remember the pest update for leek moth for the April newsletter? Reports from Keene Valley in New York show that their first leek moth of the season was found April 25. This area has a similar latitude to that of Nova Scotia, so keep your eyes peeled! 

Seasonal Considerations: Frost Tolerance and Protection

Provided by Matthew Peill, Acting Vegetable Specialist

With overnight temperatures dropping low in the last week or so, we wanted to send out a reminder on the frost tolerance of early season vegetable crops. These temperatures should serve as a guideline to assist with decisions as to when frost protection needs to be implemented in order to protect this year's plants.

With wide ranges of temperatures experienced from farm to farm within short distances of one another, it's important to check your closest weather station for the most accurate information.   

Asparagus  

Overall asparagus is very cold hardy, but emerged spears can be damaged to by frost. Spears can withstand temperature down to -2°C for short periods, but temperatures below this can cause damage.  

Brassicas 

Brassicas in general are cold hardy but there are differences between types. Cabbage and kale and are fairly hardy and can withstand temperatures of -10°C for short periods of time. Broccoli and cauliflower are less hardy and can be damaged when temperatures drop below -5°C 

Alliums: 

Garlic is very cold hardy, even garlic with well-developed tops can withstand freezing temperatures for short periods down to -10°C without damage. Established onion are also quite frost tolerant with most varieties able to handle -4°C. However, onion seedlings can sustain damage when temperature hit 0oC.  

Frost Protection: 

There are a limited number of frost protectants in vegetable crops. For most large scale planting of vegetables it infeasible to use frost protections, but for small scale production susceptible crops row covers can be used during significant cold periods to provide protection. For protected producers, make sure your side vents are down before a cold night approaches, and consider row cover in extreme situations where heating is not an option.

Production Tidbits: The Value of Environmental Sensors

The information gathered from temperature and humidity sensors in any protected growing space is invaluable. Outdoor conditions are typically amplified under cover, so we cannot strictly rely on what we are seeing from local outdoor stations to know, and make decisions on, how to manage the growing environment. Ideally our temperature sensor is going to have the ability to upload information to your phone or device of choice. This provides the freedom to check on the greenhouse, without physically having to be there and cause disruption to your order of entry protocols. These types of sensors usually have the ability to set upper, and lower, limits as well, triggering a notification to be sent once we are in a zone where conditions are above or below their ideal values. 

Identifing imbalances in the greenhouse, before the crop shows us there is something wrong, is one of the key reasons to install sensors in the greenhouse. Plants are highly sensitive to mismatched growing conditions (ex. high humidity and low temperatures), and we can see poor quality, low yielding plants as a result. Take a look at figure 2 below. The highest temperatures of the day are paired with the lowest humidities, and vice versa, which is not the ideal scenario. We are also seeing huge swings in both of these values throughout the course of the day, putting unnecessary stress on the crop to constantly adapt to new conditions. Ideally the gray line would be more consistently in the range of the light green band running through the middle of the graph, which indicates a well-matched temperature and humidity. Situations like this should be addressed as soon as possible. If left unchecked, this can significantly reduce the yield of your crop, and quality of your produce. 


Figure 2. An image depicting temperature and humidity measured over a 48 hour time-span. The gray line represents the vapour pressure deficit, or VPD value.

For the situations where we aren't constantly checking our growing conditions, sensors with a capacity to store historical information make it easier for diagnosis oddities down the line. Say for example, you have a tomato crop that has a noticeable gap in fruit production in week 35. This historical information may point to a high temperature event which lead to poor pollination and/or fruit abortion, resulting in a consistent die-back of tomato flowers. On the other end of the spectrum, our string of cold nights in the previous week could have an impact on some newly emerging tissue, that may not be obvious until further down the line. 

Feature Pest/Disease
In Nova Scotia, striped cucumber beetles (yellow-green, about 6 mm long, with three black stripes down the back) are most common. They typically make their annual debut in the Annapolis Valley end of May, early June.  These pests are problematic in many ways:
  • Feeding damage can stunt plants
  • Predated flowers reduce fruit set and yield
  • Scarring on fruit by adult beetles reduce the marketability of the crop. 
  • Cucumber beetles vector bacterial wilt. 
Bacterial Wilt:

Bacterial Wilt is caused by the bacteria Erwinia tracheiphila, which overwinter in the gut of cucumber beetles. They are picked up by insect feeding on infected plants, then is transmitted to new plants through feeding wounds created by the beetles. The bacteria spreads quickly once introduced to the plant, and there is no way to control the disease once its been introduced. This pathogen can cause significant losses in cucumber and musk melon. It can infect squash and pumpkin, but typically to a lesser degree. 

What does it look like:
Initially presents as wilting tissue during the day that recovers at night. Leaf margins eventually turn yellow/brown, and the plant is unable to recover, leaving a permanently wilted leaf/plant. One way to distinguish between this and other wilt-causing agents is to do a bacterial stream testCut through stem tissue on your cucurbit, pushing the newly cut edges together and then slowly pulling them apart is a great way to start identifying the causal agent. 


Figure 3. A cucumber plant that was diagnosed with bacterial wilt. 

Figure 4. Bacterial 'streaming' observed in a canteloupe stem (Photo Credit: University of Minnesota Extension)

As always, your Perennia specialist and/or Plant Health Lab are happy to help you through the identification process if you have some unhappy plants cropping up. 
 
Early season control of cucumber beetle is essential for limiting the direct (feeding) and indirect (bacterial wilt) impacts on your crop. Regular scouting is crucial to properly identify the risk period on your farm. Cucumber beetle control should be implemented as soon as seedlings emerge. Newly emerging cucurbit plants are particularly susceptible to stunting and bacterial wilt, while older plants can withstand up to 25% defoliation. Early treatment is essential for beetle management.

Treatment options:
Applications of foliar insecticides may be required during peak beetle activity. Row covers and/or insect nettings are very effective means of excluding cucumber beetles in pesticide free or organic production. Covers should be placed overtop of plants as soon as they are growing outdoors, and uncover when plants begin to bloom. Delayed removal of the cover will impact pollination and fruit set. 

Some longer-term strategies for managing this insect include rotate your cucurbit crops, and rely on transplants instead of directed seeding to protect the plant during its most vulnerable stages. For additional options, check out this summary on managing cucumber beetles from eOrganic. 
 
Click here for Perennia's Pest Management Guides. If you haven't had a chance to play around with our newly formatted guides, our team hosted a webinar on how to navigate the tool and showcased some of its capabilities. You can find it in the "Recent Uploads' section below if you need a refresher. 

Recent Uploads

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That's all for now! If you have any questions, feel free to reach out to your extension specialist.

Happy growing everyone!
-Talia