Irrigation in 2008 - HELP!

Issue:

Growers had extreme dry weather challenges in 2007. Most grape and tender fruit crop yields were below expectations and vine and tree health was weakened going into the winter of 2007-08. Pear losses for the fresh and processing industry were hit particularly hard. Fresh market pears were down 37% and processing pears down 52% from the 5 year average (Sept 2007 newsletter - OTFPMB). With the recent closing of CanGro Fruit Inc., peach and pear processing plant in St. David's, tender fruit growers will have to produce larger fruit to meet the fresh market demands and monitoring irrigation needs will play a huge role in future years.

NEW - Irrigation Monitoring Demonstration Project for 2008 (Funded by OMAFRA and NPF&VGA)

Two grape and two peach sites located in Niagara-on-the-Lake and Vineland areas will be monitored in 2008 using C-Probe soil moisture sensors. The demonstration project advances the 2007 COWSEP funded project "Determining Irrigation Needs by Monitoring On-Farm Soil Moisture" completed by the Brace Centre/McGill University in cooperation with OMAFRA, WIN and four growers in Ontario.

A C-Probe records volumetric soil moisture data by using capacitance sensors. The sensors are mounted on a column that is inserted into a PVC access tube in the ground (Fig. 1). A standard C-Probe may have up to six sensors on the column. The sensors can be placed at any depth required by the grower. Typically, most sensors are placed near the portion of the plant's root zone that draws the most water from the soil. WIN often uses a C-Probe recording soil moisture at 10 cm (4 in), 30 cm (~1 ft) and 50 cm (~2 ft) depths.

Fig. 1 - C-Probe installed in a vineyard (left)

The data from each sensor is processed by an electronic circuit on the C-Probe and is transmitted to a telemetry communication unit. The unit stores the data then relays it to a central base station, where they are processed. Chatham, Ontario is WIN's central processing location.

Objectives:

1. To identify gaps of irrigation information for growers;
   
   • when to irrigate, how much to irrigate, follow up scheduling
     
   • identify if the application is sufficient or surplus
     
   • introduce growers to new irrigation monitoring technology through on site demonstrations, newsletter articles and presentations
     
2. To provide site-specific information at four different grower locations in the Niagara Peninsula that would act as hub sites
   
3. To provide information to all growers through the Weather INnovations Incorporated (WIN) website available at www.weatherinnovations.com, newsletter articles and code-a-phones on the timing and how much water to use based on the hub site in their area.

Participating growers:

Peach

• Chris Andrewes site - Jordan Road, McDougal farm, Jordan Station
  
  • Cultivar - Harblaze nectarine, 10 year old
    
• Kai Wiens site - 905 Concession 2, RR6, NOTL
  
  • Cultivar - Allstar - 5th leaf, adjacent cultivars - Harrow Fair, Bellaire, Bounty, Fantasia
    

Grape

• Bill George site - 3896 Lakeshore Road, Vineland
  
  • Cultivar - Chardonnay - 21 year old
    
• Dave Lambert-Site - 370 Line 1, RR2, NOTL
  
  • Cultivar - Vidal - 12 year old

Stay Tuned:

The old rules of 1" of rain per week for fruit trees or 4 gallons per day for Concord grape vines may be useful but new technology may help growers to determine if they really have applied enough water and if it was done on a timely basis. There are still key growth phases that growers need to keep in mind when irrigating. For peaches, Stage 1 - rapid growth and cell division which lasts approximately 30 days after bloom; Stage 2 - the "lag phase" or the time of pit hardening marks the start of this phase when fruit size increase is very slow even though the embryo inside the seed is rapidly growing, the length of this stage is very dependent upon the cultivar; and Stage 3 - cell expansion which usually starts occurring 4 weeks prior to harvest. The critical stages for irrigating are Stages 1 and 3, but stage 2 should also have adequate moisture.

For grapes, keep moisture levels high for the 4 week period between bloom and fruit set when growth is rapid and water demand is high. Maintain an adequate moisture level throughout the reminder of the season reducing slightly after veraison.

Growers will need to stay tuned by connecting to the WIN website, code-a-phone and reading updates in the "Tender Fruit Grape Vine" newsletter. 2008 will be a learning year but it should provide some useful information.

Learn more:

• How to access weather data from the Irrigation Monitoring Demonstration Project
• Irrigation in 2008 - HELP! (Part 2)