Equipment Demos, Cover Crops, Mulches…and More!

On Thursday, September 28, join Horticulture Nova Scotia and Perennia Food and Agriculture for a morning filled with equipment demos, “all about mulches”, cover crops, climate-related info and more!

 

Important: As our last stop has very limited parking, we will have a bus available to transport you along the route!

Date:

Thursday, September 28 from 8:30 a.m.-12:30 p.m.

Starting location:

6727 Brooklyn Street, Kings County

 

Agenda

 

8:30 – 8:45         Meet at 6727 Brooklyn St.
Welcome and, yes, there will be coffee! Note: CEU and OFCAF points are available.

 

8:45 – 9:20         Discussion and demonstration of equipment for cover cropping and reducing tractor passes.

 

9:20 – 9:30         Travel to 99 Bligh Rd.

 

9:30 – 10:00       Degradable mulch trial results - discussion and display.

 

10:00 – 10:45     Key equipment demonstrations for mulch. 

 

10:45 – 11:00     Travel to Living Labs site on Hwy #221.

 

11:00 – 12:00     Living Labs site intro, cover crops demonstration, and lots info on related climate change adaptation.

12:00 – 12:30     Travel back to starting point; event concludes.

Hope to see you there!

Cucumber Green Mottle Mosaic Virus Confirmed in Nova Scotia

 Cucumber Green Mottle Mosaic Virus (CGMMV) is a highly infective, highly stable tobamovirus which infects members of the Cucurbit family, including pumpkins, squash, melons, gherkins and bitter gourds. The damage inflicted on the host plant and fruit can be extensive, resulting in significant yield losses. Weeds such as nightshade, pigweed and purslane can serve as alternative hosts between curcurbit crops, however the virus itself can remain infectious for many months on crop residue, soils, and growing surfaces/tools.

Symptoms of infection will vary between species and strains of the virus, however mosaic mottling of leaves is a common denominator across these variables. At the early stages of infection, the cucumber plants will continue to grow and bare fruit. As the infection becomes more severe, fruit mottling and distortion can be observed. The plant itself will eventually stop growing, or show severe distortion. Unlike some other viruses in this group, CGMMV's ideal growing conditions mimic those for cucumber production, creating a scenario that supports rapid propagation of virus particles within infected plants. 

CGMMV is most commonly reported to originate from infected seed, but is also easily spread through contact with inoculated tools/workers and existing wounds on the plant. Chewing/sucking/piercing insects, while not listed as a major source of transmission of this virus, may contribute to spread in an already infected production space. 

What can be done?

There are a handful of things that can be done to reduce the chances of infection, and reduce the risk of spreading amongst the crop once the first symptomatic plants have been identified:

1 - Purchase verified, disease-free seed from a reputable supplier. Seed saved from infected cucumber plants are likely also infected, and with its stable shelf life, the virus could survive for many years. Seed can always be submitted for additional disease testing to accredited labs if you are unsure.

2 - Establishing, and maintaining, strict biosecurity protocols on farm. For greenhouse spaces, this means:

•    Adhering to an agreed upon order of entry - the most 'valuable' plants, such as seedlings, or newly transplanted crops are visited earlier in the day, before visiting the least 'valuable plants, such as those that are nearing the end of their harvest window. Once you have been 'contaminated' by the lesser value spaces, you will not re-enter the spaces containing the more susceptible crops
• Wearing clean clothes when working with your crop. These clothes cannot come from the field, or spaces where they may have come into contact with disease-causing agents. The use of greenhouse-designated coveralls or lab coats is a good way to limit transmission of pests and disease from the outside. The same goes for footwear - having designated footwear that is worn in the greenhouse is a good way to limit accidental introductions. Alternatively, the use of footbaths containing virkon, or other sanitizing agents, can limit spread as well. 
• Designate production supplies to each greenhouse - instead of having one pair of pruners that float around between all the spaces, try and have a set for each production space. Harvesting buckets, carts, and other lower-cost items should not be shared wherever possible, to limit potential movement of diseases and pests across the farm. For larger tools (sprayers, lifts, ladders), adopt a regular schedule of cleaning before/after use to prevent accidental spread.
• House sanitizing agents (ex. virkon, alcohol, bleach) within each greenhouse for tool sterilization. 
• Regular cleaning and sterilization of greenhouse tools to prevent build-up over time. This should be done more frequently than just between cropping cycles. The timing will depend on the item - pruners should be cleaned and sterilized very regularly, whereas larger tools like carts may see this less frequently. 

3 - Ensure that your compost/waste plant material pile is located FAR away from your production spaces. Pests and diseases can proliferate in these piles, and easily be carried by wind or wings into your new healthy crops. 

•     If you have had previous issues with viruses in your space, that plant material should be destroyed, as opposed to composted, to reduce the risk of re-occuring infection

4 - Enforce a strict, regular scouting program on farm, including documentation of location, timing, severity and which pests/disease was spotted. 

5-  Stay on top of your insect pests. Allowing piercing/sucking pest populations to grow only increases the risk of disease transmission throughout the production space once a virus has been identified. 

6 - If symptomatic plants have been identified, contact your commodity specialist. Isolating this area of the greenhouse as best as possible is a good course of action in the meantime, and making sure that infected clothing/tools are not used in asymptomatic parts of the greenhouse. Disease confirmation can be done through the use of immuno strips, or most reliably through an accredited lab, before coming up with a plan of action.

 

For more information on CGMMV, check out Alberta's 2016 factsheet here

If you have any questions, or suspect infection amongst your crop, reach out to your commodity specialist for further discussion.

-Talia 

Preparing for September Storms

September is typically characterized by threats to the province by tropical storms and full-fledged hurricanes. It is important to stay informed on the timing, and track, of all monitored storms in order to give yourself as much time as possible to come up with a plan of action and prepare the farm.

Check out Environment Canada's Hurricane Track for updated information on all monitored storms.

Once the forecast becomes a bit more clear on the storm track, daily tasks can be managed to try and reduce the amount of damage caused, or overall loss. Crops that are most vulnerable to weather extremes can be prioritized in order to save as much of the crop as possible. Things like cucurbits and field tomatoes are prone to splitting after heavy rain, so would fall high on the list of things to harvest before things get going. Consider postponing seeding new plantings or cover crops in the days leading up to a significant storm. Wind and pounding rain can cause erosion and flooding, which could easily dislodge tender seedlings or wash away the seed altogether.

Preparing Your Greenhouses

Greenhouse or high tunnel structures can be dealt with in a couple of different ways in the face of an impending storm, both with their advantages and disadvantages. If there is an option to remove the plastic from a structure, the chance of structural damage can be significantly reduced. While this would expose the crops beneath, and could result in crop damage and loss, the main infrastructure can be saved. It is a difficult decision to make, but ultimately compare the value of the crop to the value of the structure itself when weighing the options. For crops that are typically terminated mid September, a slightly earlier end to the season could be less detrimental compared to the loss of a structure. 

If removing the plastic isn’t an option, make sure everything is sealed up as much as possible to prevent the wind from tearing things loose. Latch and brace doors and vents, re-enforce end walls, and tie the sides of tunnels down tight. Most structures will have a rating for maximum wind speeds they can withstand. Take into consideration any shelter/exposure provided by the topography of your farm as well as the up to date weather forecast to help make an informed decision. 

It is also advised to unplug electrical equipment where possible to prevent a surge once power returns, and ensure that drainage systems are cleared and ready for large volumes of water. Make sure that the area surrounding the greenhouse is clear of items that could be picked up by the wind, and that any weak/old overhanging tree branches have been removed. 

If you have a generator, make sure you have plenty of fuel and that it’s in an accessible place. If you don’t have a generator and require power for your watering system, make sure to give the crop a good water before things get going. Its always a good idea to try and have some water set aside in barrels in case of emergency.

The Aftermath

Besides damage by wind and heavy rains, disease issues can be a big consideration after a storm event. Heavy rain can splash fungal spore or bacteria-containing soils around, facilitating the spread of infection. Crop protectant products may be washed away, leaving the plants vulnerable until they can be sprayed again, if at all. Wind and rain may cause physical damage to the plants themselves, causing them stress and areas of damage where infection can move in. High winds sweeping up the coast may even carry insects from elsewhere, resulting in a flush of insect pressure that would otherwise be unexpected. It is important to scout your remaining crops as soon as possible after a storm has passed so that there is opportunity to mitigate any pest pressure brought on by or worsened by the weather.

In the meantime, keep track of the forecast and plan ahead as much as possible. Stay safe everyone

Winter (Greens and Cover Crops) is Coming

For those of you who anticipate winter greens production in your greenhouse rotation, now is a great time to make sure that you have your plan in place! Seeding date is crucial for plant establishment into the fall before light levels drop below critical values. Below is an example of the time to harvest for three different winter greens, and their corresponding planting dates. While these are not set in stone, and success is going to vary year to year based on climatic conditions, it demonstrates the impact that lower light conditions have on ready-to-eat winter greens:

    Spinach

• Planted September 19 --------> Harvested November 5
• Planted October 25 -----------> Harvested February 19

    Mustard

• Planted September 22 --------> Harvested October 29
• Planted October 26 ------------> Harvested February 12

Claytonia

• Planted September 22 --------> Harvested November 19
• Planted October 21 ------------> Harvested February 19

Consider the value and health of your summer cash crops when deciding which is going to make more sense for you going forward. Split seeding dates can be an effective strategy to try and get the best of both worlds, as suggested by David Blanchard in his two-part series presentation for the original 'Getting Into the Weeds' series. Anyone who is considering, or currently producing, winter greens production should check out this session! He goes into his experience growing certain types of greens, the pros and cons of different tunnel structures, and how to buffer against cold temperatures with relatively little input from supplemental heating.

                    Winter Greens Production Part 1 - Watch Here!

                    Winter Greens Production Part 2 - Watch Here!

Along that same vein, those of you who are considering implementing cover crops in protected spaces should start thinking about the plan for the upcoming season transition. Cover crop establishment is highly dependent on seeding date, alongside making sure the crop has sufficient water to germinate, and is seeded appropriately. Below is an image of a seeding date trial for a tillage radish+ oats mix implemented in 2022-2023. The greenhouse was subdivided into 4 sections, with the first planting date happening mid September shown on the far left of the image. Each of the remaining sessions were planted on a weekly basis, with the final planting date taking place mid October (far right of the first image). The amount of above-ground biomass is significantly different depending on planting date, with higher amounts of plant tissue in the early seeded treatment compared to the later one. More biomass translates to more organic matter generation in the space, which can in turn contribute to healthier soils and improved nutrient banks for next years crop. You can see a close-up of the density in the early planted cover crop on the right hand image below.

For more information on cover cropping in protected spaces, check out our session with Judson Reid from March 2023, where he discusses basic timelines and practices that will optimize cover crop performance indoors.

                    Cover Cropping in Tunnel Spaces - Watch Here!

As always, don't hesitate to reach out to our Protected Crop Specialist for all winter-greens production questions.

Posted by: Talia Plaskett

Storms: Planning for more than just your chips

 

It may seem early to start thinking about downy mildew or some of those other nasty fungal pathogens that are sure to be coming our way soon. However, as storm systems make their way up the Eastern Seaboard they usually bring spores with them from diseased fields all along the coast. In addition to transporting spores to our province they usually provide ideal conditions for fungi to colonize plants as these systems often bring with them sustained wet, cool, and humid conditions.

Downy mildew was positively identified in New Jersey last week and while it doesn’t look like storm Bret and the newly developing storm Cindy will be tracking over Nova Scotia anymore, it’s important to monitor systems coming up the Eastern Seaboard to correctly time preventative fungicide sprays and other IPM techniques such as trapping and scouting for new pests and ensuring physical barriers such as insect netting are in place as needed.

Over the last 2 years downy mildew has become a serious problem for cucurbit growers here as it is devastating when it gets a foothold in your field. Over the last 2 years both of the first confirmed occurrences in Nova Scotia happened in August, however, we need to be prepared for earlier occurrences as it is only one storm system away once it is detected along the eastern U.S coast. Along with fungal spores, these systems can bring with them novel insect pests to be mindful of as well.

Please reach out to your commodity support specialists if you have any disease or pest concerns!

Click here for excellent information on effective disease management, fundamentals of fungicides, herbicides and using weather stations for decision making on your farm

here for more information on downy mildew in Nova Scotia

Tim

Upcoming Tour for Greenhouse Soil Health

 Extra! Extra! Learn All About It!

Judson Reid and Talia Plaskett will be making the rounds in Nova Scotia July 3-July 5 for farmer-guided discussions on soil health in tunnel spaces! These sessions will be primarily focused around nitrogen management, and the crucial considerations to make when selecting nutrient inputs to make sure that we are supporting a healthy and resilient soil system, as well as maximizing the productivity on our target crops. This conversation is easily catered to production that is organic, conventional and everything in-between.  Feel free to bring your most recent soil test and tissue test results for some feedback and general discussion surrounding what those results are telling you.

Where soil health is a complex, multi-dimensional topic, the tour team will also be talking about the use of cover cropping in protected spaces. Where cover crops are hardly a new practice, the inclusion of this concept into tunnel spaces is not as commonly practiced. Cover crops offer a handful of benefits to protected producers, where erosion may not be the primary concern, but they can help facilitate drainage, fix nitrogen directly into the soil, maintain healthy microbial communities, and help to build organic matter in these highly productive, highly utilized spaces. 

The intention of these sessions is to provide a space for current and prospective tunnel producers to talk about soil health, and how protected production can lend to some unique challenges not typically seen in outdoor settings. So grab a friend, and register today for your closest tailgate meeting, for what should make for a very interesting session! 

More information can be found here

Posted by: Talia Plaskett

Cucurbit Downy Mildew was detected in New Jersey on June 13th, 2023

The first incidence of Cucurbit Downy Mildew was detected in New Jersey, United States on June 13th, 2023. Previously (in 2021 and 2022) Clade II has been detected in Nova Scotia, in the Annapolis Valley region, which predominantly infects cucumbers and cantaloupes. Clade I, which affects watermelon, pumpkin, squash, and zucchini has not yet been detected, but monitoring should still be undertaken in these crops on the chance that it does make an appearance.

It is important that growers remain vigilant and scout their fields regularly for this disease, as spores may be blown into the province by storm systems in the United States. We are not recommending protectant fungicides at this point in time, but strongly recommend weekly scouting for disease.  Downy mildew may be identified initially as water-soaked lesions that appear on the top side of the leaf, which may first appear on any region of the canopy. The most ideal time to identify these lesions are during or right after a heavy dew. The centre of the lesion initially appears chlorotic or yellow before eventually the tissue dies, becoming brown or necrotic (Fig 1 and 2). This disease is very fast spreading, the lesions will continue to spread across the canopy, and quickly kill the entire plant if left unchecked.  When conditions are humid, a “downy growth” may be observed on the underside of the initial water-soaked lesions. These symptoms may first appear before lesions on the upper leaf. This growth is particularly apparent in the morning, after a period of wet weather or dew formation.

Growers must stay vigilant, scout often, and report any positive findings they may see.

 

Figure 1: Chlorotic lesions associated with downy mildew infection on cucurbits.

Figure 2: Necrotic lesions associated with downy mildew infection on cucurbits.

If you suspect downy mildew in your field, please contact Dustin MacLean, the Field Plant Pathologist at dustinmaclean@perennia.ca or 902 324-9623.

 

 

Posted by Dustin Maclean, Horticulturalist and Field Plant Pathologist with Perennia