Grape maturity and late-season petiole sampling

by Terence Bradshaw

Grape maturity
We have begun weekly preharvest sampling of the winegrapes at the UVM Horticulture Research and Education Center. Right now, grapes are about a week ahead of last year’s ripeness schedule, and with warm/hot, dry weather this week, ripening should advance quickly. I still don’t expect harvest to begin for another couple of weeks for most varieties.
Sampling results for 2015 can be found at:

Past year’s sampling may be found at:

Petiole sampling

Growers may ascertain overall nutritional status in their vineyards at two times through petiole analysis: bloom and 70-100 days post-bloom.Now is the time for late (post-veraison/pre harvest) petiole sampling for plant nutrient status. Dr. Joe Fiola form the University of Maryland has posted some good recommendations in his latest Timely Viticulture newsletter:

  • Grape petiole analysis is recommended along with soil samples and visual observations as part of a complete nutrient management program.
  • A three year cycle of sampling all of the varieties in a vineyard is typically recommended.
  • Tissue/petiole analyses reveal the actual nutrients in the vines.
  • Spring tissue sampling is a good time to sample, as you can make nutrient adjustments to the vineyard that will influence this year’s crop quality.
  • Nitrogen status is best evaluated with tissue sampling not soil sampling.

Some specifics on sampling:

  • Each sample should be less than 5 acres; less if there are major changes in soil or topography
  • Sample different varieties separately. Samples should represent plants that are planted on the same soil type and are of the same age, variety and rootstock.
  • Vines should represent that portion of a block that is maintained under the same cultural practices, i.e. fertilizer, irrigation and vigor control practices. For example, irrigation blocks are not to be combined with non-irrigated blocks even if they are on the same soil type.
  • Do not sample vines on the border of the block or near dusty roads.
  • For the late-season sampling period, sample the petiole of the most recent- FULLY EXPANDED leaf (NOT the one across from the first blossom cluster as during bloom).
  • About 75-100 (depending on size) petioles are needed as they are typically smaller at the end of the shoot.
  • Gently wash petioles with water and gentle detergent, pat dry and place in OPEN paper bag (lunch, #6 size) to dry for a few days.
  • The closest analytical lab for grape petiole analysis is the Cornell Nutrient Analysis Laboratory . Please note that they now have partnered with Agro-One Services. It is recommended that you contact them before you send any samples to confirm that recommendations will be sent along with the analysis and to confirm costs.
    Video about petiole sampling:

Tile Drainage Field Day – planning for August Capital District

This field day may be helpful for growers interested in learning about and seeing tile drainage installation in action. Please RSVP directly to Aaron.

From Aaron D. Gabriel, Capital Area Agriculture and Horticulture Program:


We are planning to have a Tile Drainage Field Day the last week of August, provided that the weather cooperates.


Please email, text, or call me if you want to attend.  And once I know, I will tell you the date and time.


Here are the details:

  • The location will be my farm at 119 Waite Rd., Easton, Washington County.

o   One field will be tiled with a tile-plow by Travis Allen.  The 9-acre field is way out in back, the Google GPS coordinates are: 43.010097, -73.580610.  (past these coordinates into google to find the field.)  I will have sandwich board signs directing you on Waite Rd, directing you down the Henderson’s dirt laneway under the powerlines.  Follow the signs.  This is an interesting field with gentle and steep slope in various directions.  We are planning on three separate outlets.  Hudson silt loam soil.

o   I will try to have another drainage tile being laid that day in my pasture by our red barn right on Waite Rd.  This will be dug with a backhoe.

  • I will have NRCS and other experienced folks along with Travis to explain the process and answer questions.
  • To drive out to the “9-acre field”, you will go down and up a fairly steep pasture.  Should not be a problem for most cars.  It is not a far walk if you have to park before the “gully”.
  • This field day will be about the nuts and bolts of draining fields.
  • Please RSVP.
  • Please share this notice with other folks.


I hope to see you there.


Aaron Gabriel, Sr. Extension Resource Educator, Agronomy

Cornell Cooperative Extension                                     518-380-1496 cell

415 Lower Main St.                                                      518-746-2560 ofc

Hudson Falls, NY 12839                                     

Cornell Cooperative Extension

Capital Area Agriculture and Horticulture Program

ReTain applications in Vermont orchards

by Terence Bradshaw

As we see harvest coming right around the corner, the time to apply ReTain for drop control is upon us. Dr. Duane Greene from UMASS presented at the 2015 UVM Apple Program / Vermont Tree Fruit Growers Association meeting on the use of ReTain and NAA for drop control, slides from his talk can be found at:

In summary:

  • The ReTain label limits application to a maximum of 333g active ingredient per acre, but lower rates and multiple applications may be made.
  • Earlier application timing results in greater delay in ripening, later timings improve drop control.
  • Multiple applications at reduced rates may be more successful than a single application.
  • NAA (Fruitone) may also improve drop control but when used alone may advance ripening and reduce storage life.
  • NAA when applied with a half-rate or ReTain will improve drop control with less delay in ripening and reduction in red color than ReTain applied alone.

Growers should consider beginning ReTain applications on September-ripening cultivars (McIntosh, Gala, Cortland, Honeycrisp) in the next week if they have not already. Full rates may be made at this time, or half rates so long as a follow up spray will be applied. Inclusion of 10 ppm NAA may be warranted on cultivars and blocks where poor color development has been an issue where ReTain was used alone. A second application of ReTain may be made in another two weeks. This will allow for harvest of McIntosh and Gala beginning the week of September 7. For Honeycrisp and Gala, lower rates may be warranted. All ReTain sprays should include a non-ionic surfactant to increase uptake of the active ingredient. Plant growth regulator applications should be made alone without tank-mix components that may reduce material effectiveness.

August 2015 issue of Northern Grapes News



August issue of Northern Grapes News.  Here’s the direct link:


In this Issue:

-Does Production Region Matter?

-NGP Team Profile: Mike White.

-NGP Team Profile: Paul Read.

-I Have Galls in my Vineyard: Should I Call my Nursery?

-Cold Climate Wine Quality Assurance Program. 


Northern Grapes Project Homepage:

Northern Grapes Project Facebook page:

Sister “e-Viticulture Homepage:


Chrislyn A. Particka, PhD

Extension Support Specialist

Cornell University

School of Integrative Plant Science, Horticulture Section

630 W. North Street

Geneva, NY 14456

315-787-2449 (desk)

315-787-2216 (fax)

NEFCON Research and Demonstration Field Day August 20

Another meeting announcement of interest to fruit growers. New England Fruit Consultants conducts applied research and provides outreach/consultancy services to growers throughout New England. Please respond to the phone/email below if interested. -TB

New England Fruit Consultants

2015 Research & Demonstration

Field Day

New England Fruit Consultants in collaboration with Apex Orchards will present the results of this year’s field trials with various crop protection materials, growth regulators and other products that play an important role in crop production in New England. Pesticide license recertification credits (3.0) are available for attending the meeting.

Date :Thursday August 20, 2015

Location : NEFCON Research Farm / Apex Orchards

153 Peckville Road

Shelburne, MA 01370

Time : 9:00 AM – 2:00 PM

Directions : From all areas, take Rt. 91 or

Rt. 2 to the Greenfield rotary (exit 26)

Take Rt. 2 (Mohawk Trail) west 3 miles

to Peckville Road

Take right – orchard is 1/2 mile

If planning to attend, please R.S.V.P. by phone or email by Monday August 17th.

413-367-9578 (phone) TUnefcon

Program (3 pesticide re-certification credits)

9:00 AM – 9:30 AM – Welcome and orientation – coffee, juice and doughnuts

9:30 AM – 11:00 AM – Orchard tour of research and demonstration plots of interest

11:30 PM – 1:00 PM – Speaking program –

· Update on the Recent Fire Blight epidemics and Future Implications, Dr. Roberta Spitko

· Effective Management of Apple Maggot with Currently Available Tools, Dr. Rafael Vega

· Dealing Effectively and Constructively with Public Concerns about Pesticide Use at Farmer’s Markets and PYO Operations. Dr. Roberta Spitko

· Flyspeck and Sooty Blotch: Late-season Control Strategies, Mr. Glenn Morin

1:30 – ???? – Free B-B-Q lunch

Catering by Bub’s B-B-Q

“Best barbecue in the PioneerValley for over 30 years”

B-B-Q Spare Ribs, Chicken, Pulled Pork Sandwich, Dill Potato Salad

Spicy “Dirty” Rice, Orange-glazed Sweet Potatoes

Announcement – Field Day 2015.pdf

Foliar analysis and final IPM activities before harvest

by Terence Bradshaw

As the calendar flips to August, it’s time to wrap up field activities in preparation for harvest in Vermont orchards.

Foliar nutrient analysis – It is the time in the growing season to collect leaf samples for analysis. Samples are usually collected between July 15 – Aug. 15. The UVM Agriculture and Environmental Testing Lab can provide analysis, but at this time their output does not generate fertility recommendations. The following are potential options of labs for analysis. It is recommended that you contact the lab for instructions and costs before samples are sent. Plus, it is important to confirm that they will send recommendations along with the analysis.

(1) University of Maine Analytical Lab:
(2) University of Massachusetts Soil and Tissue Testing Lab:
(3) Cornell Nutrient Analysis Lab:

Wrapping up spraying – Primary insects of concern are apple maggot and codling moth. Both should be managed in high-pressure orchards. AM can often be managed with a single insecticide application based on monitoring with red sticky traps. The threshold is one fly per unbaited trap, or five flies per trap if apple volatile baits are used. Codling moth are entering their second flight in many orchards, so management is advised if this pest is a problem for you. Insecticide options are listed in the 2014 New England Tree Fruit Management Guide. Dr. Arthur Agnello discusses these summer insect pests in more detail in the July 7, 2014 issue of Scaffolds .

Summer diseases – It is important to maintain fungicide coverage to protect against sooty blotch, fly speck, and summer fruit rots. Materials should be applied after every 200 accumulated hours of leaf wetness or 2 inches of rainfall, whichever occurs first. Except on later-harvested cultivars, a fungicide application made by mid-month should provide good control through harvest. For retail orchards, fungicide sprays are likely wrapped up by now.

Remember to watch pre-harvest intervals on all products at this time of year.