Row Covers for Winter Protection in Lavender

By: Sean Westerveld, OMAF and MRA and Cathy Bakker, University of Guelph

Some lavender varieties are marginally hardy in Ontario, and most varieties can be damaged by winter conditions. Protection over the winter can reduce damage. Snow cover provides excellent protection for lavender, but is usually inconsistent in coverage and timing and cannot be relied upon for optimal protection, especially towards the end of the winter. Row covers have potential for providing protection for cultivars that are not hardy in Ontario, such as ‘Provence’, or in colder regions of the province. They could also be used to protect display gardens to ensure healthy looking plants. However, no scientific trials have been conducted in Ontario to determine if they are effective for lavender, or if they contribute to other issues such as foliar disease.

Over the past winter three row cover trials were established on lavender farms near Dundas, Freelton and Kilbride, Ontario on either angustifolia or lavandin cultivars. The cultivars used for the trial are relatively hardy in Ontario, based on the lavender variety trials currently underway across southern Ontario. A small trial was also conducted with ‘Twickle’ lavender at one site, which is known to be much less hardy in Ontario. The trials compared a thin and thick white row cover to uncovered plants (Fig. 1). The row covers were placed on the lavender on December 5, 2012 and removed on April 17, 2013 and plants were assessed on May 14 for winter survival on a 0 to 10 scale (0 = dead, 5 = half dead, 10 = no damage).

Fig. 1. Thin (back) and thick (front) row covers were compared for winter protection in lavender.

Ginseng Crop Update – June 12

Most ginseng growing areas have had heavy rain over the past week, with more in the forecast tonight. The risk of foliar Phytophthora is very high and will remain high. There are three products registered for control of Phytophthora on ginseng: Aliette, Ridomil and Maestro. Aliette helps the plant defend against Phytophthora and is systemic in its action, meaning that application to the foliage will provide protection of the roots. However, Aliette will not control infections already in place and does not provide complete preventative control. It also does not control Phytophthora in the soil. Ridomil as a granular formulation will provide protection of the roots, but will have no effect on foliar infections. Maestro will provide control of any Phytophthora that it contacts. However, control of root rot will depend on it being washed into the root zone. Timing application before a moderate rain will help move the product down the soil profile.

Heavy rains at this time of year can be used to identify wet areas in gardens to be planted this year. Growers may need to consider additional drainage in these areas, considering that additional heavy rainfalls are very likely over the life of a ginseng garden.

While the repeated rainfalls are affecting the application of fumigants, once applied, the moist soil will help to seal the fumigant in the soil if tarps are not used. Excessive rain shortly after fumigation could wash some of the active ingredients out of the soil, but light to moderate rainfall after fumigation will help to seal the fumigant into the soil.

The wet conditions will also increase the risk of Alternaria and Botrytis. Fungicide programs should target all three foliar diseases and be applied on the low end of the recommended spray interval (ie. 7 days if 7 to 14 days is recommended) until conditions become less conducive to disease development. Slugs may also build up under these conditions. Growers should also watch out for cutworms, which are being reported in high numbers in some other crops. Pythium is also favoured by moist conditions and has also been reported in ginseng gardens. Fungicides used to control Phytophthora will also have some effect on Pythium.

Heavy rains can also leach nitrogen out of the root zone, because nitrogen is highly mobile in the soil. The recommended nitrogen rate for ginseng over the whole growing season is 40 kg/ha (35 lb/acre) based on research conducted by AAFC and OMAFRA. While ginseng gets most of its nitrogen from the break down of organic matter from manure in the soil, a small application (e.g. 10-20 kg/ha) after a heavy rainfall will help to recover the available nitrogen forms. The other macronutrients, phosphorus and potassium are bound to soil and organic matter particles, and will not leach out of the soil in heavy rains. Thus, preplant adjustment of phosphorus and potassium levels is extremely important for these and other immobile nutrients.

2013 MSUE Hops Field Day & Tour – August 9

Michigan State University Extension is hosting their annual Hops Field Day and Tour on Friday, August 9, 8 am – 5 pm.

Tour locations include: Empire Hops (Leelanau Peninsual), Fresh Roots Organic and New Mission Organic hop yards as well as a tour of Brewery Terra Firma (Michigan’s first farm brewery).

Hop growers will be on site to discuss all aspects of hop production; initial costs, plant care, disease and insect management, short and tall trellis systems, trellis construction, and organic and conventional growing practices.

Dr. Heather Darby, professor from the University of Vermont, will be in attendance to discuss hop growing practices, challenges and recommendations from the Northeast United States.  The group will then return to the Research Center for research trial updates, followed by an educational beer tasting led by Scott Graham, Executive Director of the Michigan Brewers Guild.

Cost: $80 per person (includes lunch and transportation by charter bus).

Pre-registration required, space is limited to the first 56 registrants.

Meeting location: MSU Horticultural Research Center, 6686 S Center Highway, Traverse City, MI 49684.

For more info or to register, please visit the website: hops.msu.edu.

Or for questions, please contact Rob Sirrine, at the Leelanau MSU Extension office at 231-256-9888 or msue45@msu.edu.

Program sponsors:  Michigan Brewers Guild, Michigan Hop Alliance and Brewery Terra Firma.

Ontario Haskap Day – June 22, 2013

Boreal Berry Farm & Winery in Warren, Ontario is pleased to host the first Ontario Haskap Day on June 22, 2013.

Guest speaker Dr. Bob Bors, Head of the Domestic Fruit Program and Assistant Professor in the Department of Plant Sciences at the University of Saskatchewan will be giving a workshop on haskap production and other hardy fruits.

Date & Time: June 22nd,  2:00 pm
Location: Boreal Berry Farm & Winery, 748 Little Brule Road, Warren, Ontario

For more information and to register please contact Boreal Berry Farm & Winery: Email- borealberryfarmwinery@gmailcom or Tel – 705.920.7096.

Website: http://www.ontariohaskap.ca/boreal-berry-workshop.php

Hop Fertility Overview – June 11, 2013

Final fertility applications should be scheduled throughout the month of June with no more than 25 kg N/ha applied at one time.  Flower (burr) development will begin the week after June 21 (due to the change in photoperiod to decreasing day-lengths), and main nitrogen fertility applications should be discontinued at that time to reduce excessive vegetative growth during cone development.

Currently there are no Ontario fertility recommendations for hops, however, we can learn from other jurisdictions with similar climates or soil types about the basics of hop fertility and by considering nutrient requirements for similar plant species.  OMAF’s Specialty Cropportunities web database has detailed information on fertility planning for specialty crops (including hops): www.omafra.gov.on.ca/CropOp/en/general_agronomics/nutrient_management/fertility_recommendations.html (refer to Table 3 for the most similar traditional crop to specialty crop for suggested approach to fertility planning).  Fertiliser requirements will vary by soil type and location, so decisions should always be based on the results of a soil test from your farm.  Although nitrate-nitrogen tests are offered in Ontario, results can be extremely variable between sampling periods due to the high mobility of nitrogen ions and are therefore difficult to use for general fertility planning.  Please refer to the OMAF website for a listing of accredited soil testing laboratories in Ontario:  www.omafra.gov.on.ca/english/crops/resource/soillabs.htm.

Extension networks in the north-east United States, including University of Vermont Extension (UVME), suggest nitrogen application rates of approximately 66 -133 kg N/ha during the establishment years and 133-151 kg N/ha for established hop yards. More information is available on their website: www.uvm.edu/extension/cropsoil/wp-content/uploads/HopFertilityManagementNE.pdf.

Oregon State University Extension (OSUE) have noted studies based in Germany and Washington State demonstrating that phosphorus requirements for hops are low, in the range of 0-33 kg P/ha.  Additionally, potassium requirements typically range between 0-150 kg K/ha (OSUE Fertilizer Guide – Hops: http://extension.oregonstate.edu/catalog/pdf/fg/fg79-e.pdf).

Fertilizer applications should begin in the spring (late April) and continue every 2-3 weeks applying split applications with no more than 25 kg N/ha at any one time until early summer (late June).

Haskap Update: June 4, 2013

Evan Elford, New Crop Development Specialist, OMAF and MRA

Haskaps are beginning to turn colour (Figure 1) which means birds will be more interested in the berries!  In Simcoe, we have had ongoing issues with birds in our haskap trial, particularly robins.  The goal is to implement control measures before the crop is attractive to birds which may be long before the crop is ready for harvest.

Figure 1: Ripening haskap berries (Indigo Treat), June 4, 2013.

This year we have used 19mm ( 3/4″) diamond shaped bird netting draped over 1.2 m (4′) posts and secured to the ground using ground staples (Figure 2).  A partial list of bird netting suppliers is listed on the OMAF website: http://www.omafra.gov.on.ca/english/crops/resource/info_birdnet.htm

Figure 2: 19 mm bird netting over haskaps on 1.2 m posts.

Some other bird management options such as visual deterrents and electronic sound devices are outlined in OMAF’s Pub 360, Guide to Fruit Production: Bird Control: http://www.omafra.gov.on.ca/english/crops/pub360/9bird.htm 

We have also noticed some brown spots appearing on a few of the berries this year (Figure 3).  Have you seen similar damage in your area?  Please share in the comments what you are seeing in the field and what you suspect to be the issue.

Figure 3: Brown lesions/spots appearing on some haskap berries.

 

The author would like to thank Chris Hedges, Orchard Post and Orchard Supply, for providing the posts in the haskap trial located at the Simcoe Research Station.

You Can’t Measure with Your Eyes: The Importance of the Timed Output Test for Calibrating Ginseng Sprayers

By: Dr. Jason S.T. Deveau, Application Technology Specialist, OMAF and MRA

Walking a boom to see if the nozzles are emitting an unbroken pattern is a good habit. This will tell you if the tips are on or off, and may tell you if there is a minor blockage distorting the spray quality. The problem is, unless the tip is emitting more than +/-50% than it’s neighbours, you will not be able to tell. Even then, you need a very good eye to see the difference.

We recently calibrated a trailed ginseng field sprayer. The nozzles on this sprayer are not conventional nozzle tips. They are the assemblies found on the ends of spray guns (see figure 1). Nevertheless, they terminate in a ceramic disc with a 1.5 millimetre oraface, very much like a conventional nozzle.

Figure 1 – Trailed ginseng field sprayer with ARAG Microjet® nozzles

The grower explained that this sprayer applied 100 US gallons / acre. He knew this because of where the tank emptied in his fields. We filled it with water, confirmed that the pressure gauges were accurate by comparing them to a known standard, and brought the boom up to 100 psi.