Thursday, May 30, 2013

Black Raspberry Research in NC (and OR, NY and OH)

Hi everyone, I’m Christine Bradish and I’m a PhD student here in the Rubus breeding program at North Carolina State University.  My research is part of a national USDA-SCRI sponsored grant that is taking place in Oregon (USDA-ARS), Ohio (OSU), New York (Cornell), and here in North Carolina (NCSU), and is focused on improving black raspberries for disease and insect-resistance, wider production ranges, and increased market awareness.  Black raspberries are native to North America and have been cultivated since the late 19th century; however diseases and a narrow gene pool has led to a severe decline in production over the last 75 years.  Currently, black raspberry production is focused in the Pacific Northwest and the berries are used in processed products, such as jams, jellies, ice creams, and baked goods.

Black raspberries harvested from Jackson Springs, NC on May 29, 2013.
As part of the project, we have identical plantings of 275 black raspberry plants at locations in all four states.  The fields were planted in April 2012, and will be evaluated through 2014.  My responsibility is to take data on approximately 40 different traits for each plant, ranging from heat tolerance and disease resistance to fruit size and thorn shape.  An example of the levels of a trait, fruit set is below. 
Measuring fertility of plants: poor fruit set (above)  versus fully fertile fruit (right). 

Yesterday was exciting, because we had our first harvest!  The fruit is as good as it looks. I along with the rest of the group of scientists involved in this research will be providing updates throughout this project, as we start to learn more about this exciting crop.

We have a website linked to this project:

Here is the USDA NIFA page:

Monday, May 20, 2013

What will your raspberry and blackberry prices be in 2013?

I am posting the content below to increase the number of responses. This note was written by Debby Wechsler, the Executive Secretary of the North American Raspberry and Blackberry Association.

"The North American Raspberry & Blackberry Association is conducting a survey of growers' prices for their raspberries and blackberries, especially focusing on those growers who sell direct to the public, either pick-your-own or at farm stands and farmers markets. We also ask about wholesale on a small scale, perhaps to other farm stands or local restaurants, as wholesale prices on a larger scale are pretty much beyond individual growers' control.

If you are a grower: please visit, and fill out our quick and easy price survey.  This is a quick and easy way for us to collect this information.  

If you don't yet know 2013 prices, report 2012 prices or give your best guess.
If you absolutely hate online surveys, you can email the NARBA office with your information. Remember, for each price, we need to know the type of berry, unit size, and whether already picked or or PYO.

Please respond by June 3,

If you are an extension person, please invite other growers you work with to participate in the survey.

All responses are confidential and no farm will be identified by name. A report of the survey will be published in the June issue of The Bramble, NARBA's newsletter. Non-members who respond will receive the report by email.

Thank you for participating!"

Friday, May 17, 2013

Bud damage in Pennsylvania

Kathy Demchak, Extension Specialst at Penn State University, sent me these photos. At their research farm in College Station, they experienced temperatures at canopy height 24-27F on the night of  May 14-15. These are images from Illini Hardy.
Figure 1. Illini Hardy shoot, flower buds show no visible damage. Photo KD, PSU. 

Figure 2. Same shoot with buds cut open, with darkened tissue in buds.  Photo KD, PSU.
We saw the same thing occur last year (2012) in April. We had a wide range of damage in NC last year and some growers lost more of their crop than others.

See my blog post for a discussion of what I recommended.

Note: Although the name, Illini Hardy, would suggest this variety would be less susceptible to freeze injury, these photos indicate that buds of Illini Hardy are just as susceptible to damage as the Arkansas cultivars that we grow in NC. However, Illini Hardy dormant plants can tolerate lower temperatures than other blackberry varieties in the winter and is therefore grown in regions normally not considered suitable for blackberry production. It is not recommended for North Carolina.

Tuesday, May 14, 2013

Wednesday, May 8, 2013

Pondering blackberry harvest dates for 2013?

Below is a list of harvest dates from blackberry trials that we have conducted in North Carolina since 2008.  The trials were at three locations in NC, the Piedmont Research Station in Salisbury, the Mountain Horticultural Crops Research and Extension Center in Mills River and at the Upper Mountain Research Station in Laurel Springs. The trials were replicated with plots both under high tunnels and grown outside at all three locations. First harvest is approximately the date when 5% of the fruit from the entire season was harvested, peak harvest is when 50% of the total crop was harvested and 95% represents the last harvest date. There are 7 different blackberries represented, most were at all of the trial locations. Harvest dates do vary from year to year and with location. For example, the earliest and latest harvest dates for Navaho was 18 June 2010 in Salisbury,  and 31 July 2010 in Laurel Springs respectively. We don't have a model for NC, but I thought this may help you with determining dates for your farm. 

Monday, May 6, 2013

Heat units for determining blueberry ripening dates

According the the NCSU heat unit model, blueberry ripening is a few days behind schedule. Blackberries don't have the same model (yet), but based on the extended cool spring temperatures so far, blackberry ripening dates may be late as well. 

Read on for more information about the blueberry model.

NCSU has developed a model to predict fruit ripening in blueberry. The growers use it in combination with chilling units to determine ripening dates for the current season. Here is a link to their model.

The Model begins when there is 25% petal fall on Croatian at Ideal farm near Wilmington NC,  and ends when there is 25% ripe fruit on the same bushes.  This year the  model began on April 17th.  The daily values are calculated based on average hourly temperatures through each day.

The model is as follows:
Average hourly temperatures 65 and above count as a point
Average hourly temperatures from 55 to 64.9 count as a half a point.
Average hourly temperatures from 45 to 54.9 have no value
Average hourly temperatures below 45 you loose a point.

According to Benny Bloodworth, NCSU researcher, "Comparing what we have so far to other seasons we are quite a few days behind schedule at this point.  Once we get to the first week in May we will be able to draw more definite conclusions about ripening dates for the 2013 blueberry season."