Wednesday, June 17, 2015

More on the heat and fruit harvest

As the temperatures look to be staying quite warm this week and next just as harvest starts...here are some thoughts.
-keep the plants irrigated, they are transpiring a lot with the heat. all that water is pulled up through the plants, and berries. 
-berries are 90% water, so as they increase in size this week, a lot of that size is due to water uptake
-harvest as early in the day as possible, to minimize soft and hot fruit.
-consider going to a night harvest? Its been done in grapes and apples. 

Heres how they do it in apples an article from good fruit grower. It might not work for you now, but something to consider.
http://www.goodfruit.com/night-shift-harvesting-apples-at-night/

Harvesting apples at night

Monday, June 15, 2015

Worlds Blackberry, Raspberry, Currant and Goosberry Experts coming to North Carolina


From June 19-24, North and South Carolina will be the hosts to the XIth International Rubus and Ribes Symposium. This is a group of scientists and industry professionals that come together every 4 years to share research findings, develop new collaborations, renew old friendships and talk about blackberries, raspberries, currants and gooseberries for almost a whole week non stop! To some of you this may sound boring, but to us, this is one of the highlights of our careers.

Why North Carolina? Well, the Rubus and Ribes group has not met in the US for over 30 years, and the last time was in the Pacific Northwest. Four years ago, when they were meeting in Serbia, the southern US was suggested because of the dynamic fresh market industry that had developed over the past few years.  The Rubus and Ribes Working Group asked and NC State University agreed to host the XI International Rubus and Ribes Symposium in 2015.

This meeting is being held in 2 parts. A smaller group (about 75 people) will take part in the Pre-Symposium Tour. Later this week, we will gather in Charlotte, NC and fan out for 3 days visiting growers and research facilities.  We will visit 5 farms, the NCDA&CS Research Station, and the Plants for Human Health Institute. Then we head up to Asheville for 3 days of scientific meetings with a half day break for local farm tours. We are expecting 170 people from 26 countries to attend the Symposium.

If you want to follow what is going on, the XIth International Rubus and Ribes Symposium is on Facebook (https://www.facebook.com/ISHSRubusAndRibes), Twitter (@rubusribes2015) (#rubusribes2015), Instagram (rubusribes2015), and Pintrest (rubusribes2015). Like, tweet, post and share with us.

This is an event held under the auspices of the International Society for Horticultural Science.

White Drupelets in caneberries 2015







Conditions are favorable for white drupelet this week. I have already gotten calls this morning and expect more as the day goes on. Here is a great explanation of White  from UC Davis/Mark Bolda  http://www.ipm.ucdavis.edu/PMG/r71800111.html

White drupelet is a tan-to-white discoloration of one to many drupelets on the fruit. Most often, white drupelets will appear when there has been an abrupt increase in temperature accompanied by a drop in humidity; it is especially pronounced when there is wind. In the Monterey Bay area, white drupelet typically occurs when temperatures that are fairly steady around 70°F suddenly go above 90°F, and there is an absence of fog.

While white drupelets may seem to be directly caused by weather, they are actually caused by ultra-violet (UV) radiation. Weather conditions modulate this by the effect they have on penetration of UV radiation into the fruit. Cool, humid air scatters and absorbs UV radiation, while hot dry air has the opposite effect and allows more direct UV rays to reach the fruit. The movement of humidity away from the canopy by wind only heightens the effect of hot dry air. Additionally, as humidity is moved away from the plant canopy, more UV rays penetrate the canopy and damage fruit that may not even have been exposed to the sun. Fruit inside of the canopy is not acclimatized to UV radiation and is subsequently more susceptible when it reaches them.

Some growers of caneberries in the Willamette Valley of Oregon, where rapid changes from a normally mild climate to temperatures up to and above 100°F occur through the summer, use overhead irrigation to minimize fruit loss to white drupelet. This is not merely to mist the fruit; instead, large amounts of water are applied to thoroughly wet the canopy and maintain cool temperatures and high canopy humidity for as long as possible. Sprinkling is not done too late in the evening to allow fruit to dry before nightfall.

While some varieties, such as Apache blackberry, Kiowa blackberry, and Caroline red raspberry tend to get white drupelets more frequently than others, almost all caneberry varieties are susceptible to white drupelet to some degree.



My additions:
  • Tolerance for white drupelet varies to some extent by grower. Growers that ship berries have no tolerance, while pick-your-own growers can tolerate a few white drupelets (see last point, educate your clientele).
  • White drupelet disorder is usually a problem early in the season and then disappears.
  • The berries are still edible, they make delicious pies, juice, ice cream...

Wednesday, June 10, 2015

Bud removal to mimic freeze damage in the spring

video
This spring we set up demonstration trials at 2 locations in the state to monitor what would happen if we mechanically removed buds at critical times during flowering. We wanted to mimic what may happen when we get bud kill to flowers in the spring due to freezing temperatures. One of the trials is at the Sandhills Research Station in Jackson Springs, Josh Mays is overseeing the trial on the cultivar Ouachita. He removed buds at four times in the spring, has taken lots of data and lots of pictures. Here is a short video of what we saw today. He will be sharing more at grower meetings this upcoming year.

The other trial is at the Mitchem Farm in Vale NC. I'll post about that one later...

Saturday, June 6, 2015

Summer Caneberry Chores

Summer  2015
Caneberry Chores

This list was developed by Dr. Gina Fernandez, Small Fruit Specialist at NC State University.  Chores and timing may be somewhat different in your area or for your cropping system.

Plant growth and development
Fruit development for floricanes fruiting types
Rapid primocane growth
Flower bud development for primocane fruiting types later in summer
Floricanes senesce

Pruning and trellising

Floricane-fruiting raspberries:
May need to adjust primocane numbers if canes are too thick (i.e. remove less vigorous primocanes at their base)
Train primocanes to the trellis
Pinch black raspberry primocanes at 2 to 3 ft. to promote lateral growth

Primocane-fruiting raspberries:
Train primocanes within a trellis to hold canes erect

Erect floricane -fruiting blackberries
Tip the new primocanes when they are about 6” to 12” below the top wire of the trellis to encourage lateral branching
Continue tipping at monthly intervals to maintain desired branching and height of canopy (laterals should reach top wire)
Prune out spent floricanes after they have produced fruit, do not thin out primocanes until mid-to late winter
Train primocanes to trellis to minimize interference with harvest.  Shift trellises or V trellises make this relatively easy

Trailing floricane-fruiting blackberries
Train new primocanes to middle of trellis, on the ground in a weed-free area, or temporarily to trellis outside of fruiting area (depends on trellis type)
Cut back side shoots to 18” (after dormancy in cold climates)
Remove spent floricanes after harvest

Primocane-fruiting blackberries
Tip canes at 3-4 ft to increase branching and fruiting potential.

Weed management
Mow along side of row to maintain the width of the bed to 3 to 4 ft.
Weed growth can be very vigorous at the same time as the bramble crop peaks.
Weed control is best done earlier in the season before harvest commences.
Mow middles regularly to allow pickers to move through rows easily.

Insect and disease scouting
Scout and treat for these pests:
Spotted winged drosophila
Raspberry crown and cane borers (canes girdled and wilt)
Psyllid
Two-spotted spider mite
June beetle
Japanese beetles
Stink bugs
Fire ants
Scout for diseases
Botrytis
Rusts
Orange felt (orange cane blotch) (blackberry)
Sooty blotch (blackberry)
Orange rust
Powdery mildew
Double blossom (blackberry)
Cane blight (blackberry)
Powdery mildew

Water management
Raspberry and blackberry plants need about 1-2 inches of water/week; this amount is especially critical during harvest.
Give plants a deep irrigation after harvest.
Nutrient management
Take leaf samples after harvest and send to a clinic for nutrient analysis
Blackberry growers should give plants additional nitrogen after harvest, check with your local recommendations.
Harvest and marketing
The busiest time of the year for a blackberry or raspberry grower is the harvest season. Each plant needs to be harvested every 2-3 days. For larger plantings, that means fruit is picked from some part of the field every day of the week.
Pick blackberries when shiny black for shipping. Those that are dull black are fully ripe and suitable for PYO only.
Pick directly into clamshells with absorbent pads, or for PYO use clean cardboard flats, take-home baskets, or sanitized re-usable containers.
Keep harvested fruit in shade and move into coolers as soon as possible to lengthen the shelf life of the fruit.
Use forced-air precoolers for best removal of field heat.
Store at 32 to 34°F and 95% relative humidity.
Freeze excess fruit for jam, juice, or wine.
Keep good records of what cultivars are picked, what fields are picked and when they are picked. Good record keeping will help you predict harvest  potential in the future.
Keep your customers informed with social media.


Thursday, May 28, 2015

How can I tell the difference between a primocane and floricane leaf or cane?

So this time of year there is a lot of new growth in the blackberry field. Both floricanes and primocanes are present and providing the plant the food via photosynthesis that occurs in the leaves.  This food (carbohydrates) help to ripen the fruit.

Most of the floricanes are loaded with green fruit by late May, and look like this image below. shorter laterals, short internodes relatively small leaves with 3 leaflets. FYI, caneberries have compound leaves, meaning each leaf has more than one section or leaflet.
Picture 1. Floricane with fruit.

The primocanes usually have thicker stems, that gradually taper at the tips,  and long internodes (area on stem between each leaf). They look like this:
Picture 2. Primocane Note that each leaf has 5 leaflets.
Then there are these canes, at first they look like a primocane, but then with closer inspection, they have little flower buds and only 3 leaflets per leaf.
Picture 3. This is a floricane, note the leaf is comprised of 3 leaflets.
So, there are two types of floricanes, the ones that produce the majority of the fruit on the canes that developed last year. Then there are basal buds that are much more vigorous (and look like primocanes) and produce fruit later in the season (Navaho is probably the variety where we see if most often). Here is a picture of the basal floricane and the primocane. Note that not only does the floricane have fruit, it has 3 leaflets per leaf. Most blackberries and raspberry floricanes have 3 leaflets and primocanes with 5 leaflets.
Picture 4. Floricane with 3 leaflets/leaf  and small flower buds on left, primocane with 5 leaflets/leaf on right.

So, when you are wandering through your fields, take a look, can you tell the difference?