Friday, June 22, 2018

It's getting hot out there, time to try a night harvest?

Last summer we conducted a small study looking at the possibility of night harvest for blackberries.

Briefly this is what we found:

  • Headlamps worked well. We used some that were rechargeable LED headlamps. They were about $20, from Amazon. There are other sources. Don't get the cheap ones they don't give you enough light. 

  • The fruit temperatures and air temperatures were almost identical last year, when we did our 24 hr study. We saw a 30F difference in temperatures, with a minimum temperature of 58F around 3 am and a high of 85 at noon.
  • The fruit never got wet BUT THE LEAVES DID.  The dew formed on the leaves around 1 am. The dew from those leaves was knocked onto the fruit during harvest and impacted the fruit quality. So, we think that after the leaves get wet, it is time to stop harvesting to prevent fruit from getting wet.
  • You many not want to harvest all night, but if you harvest late into the evening, those cooler temperatures may give your workers a more comfortable working environment and may improve fruit quality. 
Here is a link to the post from last year.

Friday, June 15, 2018

Blackberry season 2018: looking forward to a great harvest, some problems to watch out for along the way

The blackberry season just a few days to weeks away, depending on your location. Some of the more common problems that are likely to be seen are:

1. Cane blight. This is one of the most common diseases in blackberry plantings. The tips of the floricanes are necrotic and have a brown/silvery appearance. The canes became infect last year when they were primocanes and were tipped. The wound created by tipping allowed the disease to get into that large wound. To minimize the infection it is best to tip when the canes have a very small diameter. More information here:

2. Viruses. This was one of my first challenges that I met when I started  at NCSU. Back then, several  new plantings were riddled with virus symptoms. Thanks to a clean plant program, from tissue culture to nursery, to institution of improved cultural practices, viruses are not as prevalent now. More information here:

3. Poor fruit set/fruit not ripening. This could be a result of a number of things. Poor pollination during flowering, rain during flowering, but more likely this year to injury to the flowers during the spring. Some fruit never developed as is seen in the first image. You can see in the second image the damaged and not damaged flowers. Those that were damaged will not develop into fruit. For more information on damage from cold, click here

4. Leaves suddenly wilting on floricanes. This can be due to a number of things, winter injury, wind damage, crown borers or rodent damage. Here is a link for more information. Picture of wilting raspberry floricane courtesy of Kira Chaloupka.

5. Orange spots on canes, also known as Orange Felt or Orange Cane Blotch (Cephaleuros virescens). This occurs in warm humid fields in the central, eastern and southern parts of NC. It is also in other states in the south. It is a parasitic algae, so even though at first glance it looks like a disease, it is not. Here is a link with some more information.

6. White Drupelets. Although most cultivars can get white drupelet, we see this in Apache more than others. Here is a link with more information.