Fall Color in Blueberries

Ah, fall.  That time of year when a respite from oppressive heat and humidity comes to south Mississippi. Fall, to me, is the best time of year.  Growing up in Michigan I appreciated the great leaf color show every year. If pressed, I will admit to missing that (but not the awful dreary weather that comes with it).  Most of the plant species in south Mississippi are not known for their fall color. Sure, there are some Swamp Red Maples (Acer rubrum) and Sweetgums (Liquidambar styraciflua), but most don’t have really good fall color. One primary reason for that is the lack of cold temperatures. Blueberries do have some fall color, some cultivars and species more so than others.  But, let’s talk more about why fall color happens in the first place.

Many blueberry leaves turn red in the fall — or so it seems.  Actually the red pigments are there the whole time, it is just that the chlorophyll (green) overshadows the other colors. In the fall, these chlorophyll pigments degrade, leaving behind the red and orange colors. Chlorophyll breaks down in sunlight so the plant needs to continue synthesizing new chlorophyll to keep the green color in its leaves. The conditions that promote this are warmth and sunshine, both at their peak during summer. Part of the chlorophyll degradation is the plant preparing for winter — it is reallocating nutrients back to the root system. Since leaves are mainly disposable on deciduous species, it makes sense for the plant to take nutrients like Nitrogen and return it to a permanent plant structure. Once stored in the roots it can be reused in the next year.

Blueberries have anthocyanins in the leaves. Once the chlorophyll is lost, the leaves appear red due to the color spectrum of light it is absorbing. This is a natural process that helps the plant maintain leaves while it reallocates nutrient reserves to the root system.  Of course there are times of the year when we don’t want to see red leaves on blueberries, especially in the spring after a frost/freeze event, but seeing red during the fall is a natural, normal thing that portends the coming winter.

Great red fall color can be seen on commercial blueberry cultivars, but also native Vaccinium species like V. elliottii and V. darrowii. Below is a photo of ‘Springhigh’, a southern highbush blueberry released from the University of Florida blueberry breeding program.

Fall color of 'Springhigh' blueberry

Fall color of ‘Springhigh’ blueberry

Many blueberry plants are still green here in south Mississippi. Many won’t turn red, or at least not completely, before falling off the bush. Some cultivars retain their leaves throughout the winter. So much variation among blueberry cultivars and species! Enjoy the fall — while it lasts.

Measuring Grapevine Growth

For three seasons I have had a study going on how grapevines respond to producing a crop in the season after they were planted.  In 2013 I planted three cultivars — Blanc du bois, Villard blanc, and Miss blanc.  In that first season I was able to get them trained onto the cordon wire (single wire high curtain system). In season two I had three different treatments: removal of blooms, removal of fruit at veraison, and harvested fruit.  In season three, all vines were harvested (some even going to produce a commercial product, but that is a discussion for a later post) and today I measured trunk calipers.  I have not analyzed the data yet, but I will look at cultivar and treatment effects on vine trunk size.  Below is a photo of the process:

Caliper measurements on a grapevine trunk

Caliper measurements on a grapevine trunk

I have a little more data to collect and then I will be able to start analyzing the data and writing up the results. This study was also done in Oklahoma before I moved to Mississippi, only with different cultivars. It will be interesting to see how the results compare. Growing grapes is expensive and growers need to start recovering expenses quickly. If grapes can be harvested starting one year earlier then the time to recover initial capital outlay will be shortened.  However, we need to make sure that has no lasting impact on vine health, thus this study. Since I couldn’t find any other studies like it in the literature I decided to answer the question myself.  And soon, I will find out the results.  It is exciting!

MS Pecan Fall Field Day 2015

Pecan Fall Field Day 2015

When to Harvest Pecans
Harvesting of Pecans
Post-harvest Cleaning and Storage (Food Safety)
Winter Care of Trees
Grading Pecans for Sale
Nursery Tour

Thursday, October 8
Registration 1:00 – 1:30 p.m
Program 1:30 – 5:00 p.m.

Pecan Hill Farms
19470 Highway 18
Raymond, MS 39154

For more information, please call Max Draughn 601-594-4393

Alternative Uses of Fruit Crops

Sometimes I think we put certain fruits into a narrow box and they can only exist in that form.  Grapes can be wine, juice, or fresh eating.  Oranges can be juice or fresh.  Apples? Fresh or juice.  Those ideas lack creativity. How else can fruit be used that is out of the ordinary?  I have some friends in the craft cocktail and brewery industries.  Those folks know that interesting and compelling flavors can drive sales.  That got me to thinking about the passion fruit that I was harvesting.  What can I do with it?  I could eat it fresh, but there are so many arils each filled with a seed.  I could dry them and then suck on them like candy.  I could juice them and drink the juice or make wine from it; however, the chemistry just isn’t there to make a good product.  So what to do?  My decision was to make a passion fruit syrup.  It was easy and turned out pretty darn good (although when using it in a drink a little goes a long way in terms of flavor).

Passion fruit syrup

Passion fruit syrup (the peppers are for looks only in this photo, I did not use them in the recipe).

Passiflora incarnata is a native fruit (some say weed) that has some tropical fruit notes, which makes it desirable.  However, in order for me to get the pulp out, I had to remove the outer rind by hand. There is commercial-grade equipment out there that would make it easier (I think), but for now it was easier to do by hand.  It is time consuming, but the outcome made it worthwhile. To make the syrup I started with about 24 ounces of juice.  I reduced it by about half, then added 1.75 cups of sugar.  It depends on how sweet you like it.  The juice was acidic and not too sweet so I needed to kick the sweetness level up a little.  I stirred the sugar and the juice together and voila! A passion fruit syrup.

Agenda for 2015 Muscadine Field Day

Below is the agenda for the 2015 Muscadine Field Day.  It will be held tomorrow morning.  More detailed information, including location, times, etc. was published on this blog here: https://msfruitextension.wordpress.com/2015/07/14/mississippi-muscadine-field-day-2015/

2015 Muscadine Field Day Agenda

2015 Muscadine Field Day Agenda

Passion Fruit Harvest

Two days ago I harvested some native passion fruit (Passiflora incarnata) from my research vineyard.  It was planted in places where I did not have grapevines.  Last year it produced some fruit, but this year the bounty is larger.  I harvested a 3-gallon pot worth of fruit in short order.

Harvested passion fruit

Harvested passion fruit

As you can see, some were riper than others but all were taken off the ground.  That is one of the management issues with passion fruit of this species, as the fruit falls off when ripe (or even not quite ripe).  So lots of time is spent on hands and knees or stooped over.  I have a few different wild vines and there is variability in fruit size and shape.

Size variability in wild passion fruit (P. incarnata)

Size variability in wild passion fruit (P. incarnata)

Now I have the fruit, what do I do with it?  My plan was to create a syrup from the juice.  I peeled off the outer rind and put the inner arils with seeds into a bladder press.  Eventually I ended up with about 24 ounces of juice.

Passion fruit juice after pressing

Passion fruit juice after pressing

I did not check the brix but I did taste it and the juice was tart.  It will need some sugar.  I hope to start doing more work with passiflora in the future.  Passiflora incarnata is a fascinating plant with great potential.  All it takes is time, money, determination, support, etc.

A Year with No Fruit

This year I have received several calls wondering why certain trees and vines produced little or no fruit this year.  It is a fair question — what would cause this problem?  Assuming there really was no fruit or the fruit failed to develop properly (rather than a disease issue) the answer points to pollination.  Will all the rain and cool temperatures we had this spring, conditions were poor for pollination in some crops in some locations.  Some crops that I have seen with poor or no crop this year are pears, peaches, pecans, and muscadines.  I’m sure there are plenty of others as well.  Rain and cool weather deters pollinators from visiting open flowers.  Rain also dampens the pollen itself and makes it so that it cannot readily be dispersed. Timing is the critical thing, as one cultivar may have a full crop and another nothing.  It could even vary from plant to plant of the same cultivar, and also from field to field (i.e. a neighbor might have a good crop whereas you have little or nothing). So the interaction of rain and flower opening is where things can go wrong.  Of course other things can reduce pollination (lack of pollinator insects, lack of pollinizer trees, disease, frost, drought, excess heat and humidity, etc.) but this year I put my money behind the wet and cool conditions.

This pecan tree, located in Poplarville, MS, has no nuts at all

This pecan tree, located in Poplarville, MS, has no nuts at all.

It is not just trees that had a hard time this year.

'Fry' muscadine with no fruit

‘Fry’ muscadine with no fruit.

Some cultivars were impacted but were able to set some fruit, although it will not be a full harvest by any means.

'Janet' muscadine with some fruit, but limited by poor pollination conditions.

‘Janet’ muscadine with some fruit, but limited by poor pollination conditions.

Is there an upside to not having much fruit this year?  Well, bud fruitfulness should be increased for next year, especially in the pecan trees.  So, just like the mantra of the Chicago Cubs — There’s always next year!

Firmness and Splitting in Grapes

This year I harvested several different cultivars of grapes for the purpose of seeing what kind of firmness and splitting data I could get.  It was not a true study, just a quick “look-see” to get an idea of how it would work.  Below is some of the observations I was able to get (will help from Dr. Donna Shaw and Lavonne Stringer). Brix (sugar levels) were recorded first to see how high they were at harvest.  Nine cultivars were chosen — Blanc du bois, Champanel, Cimarron, Conquistador, FAMU99, MidSouth, Miss blanc, Victoria Red, and Villard blanc.  As you can see below, sugar levels were low for most, although these were only samples and the entire vine was not necessarily harvested.

Brix measurements of 9 grape cultivars

Brix measurements of 9 grape cultivars.

Individual berries were then tested for firmness, as seen below.  In most cases, the lower the brix, the better the firmness. This is not surprising as unripe berries would be expected to be firmer.  One big exception was Conquistador which was the firmest berry by far, even at nearly 18 brix.

Firmness of nine grape cultivars.

Firmness of nine grape cultivars.

Finally we looked at how the berries split if exposed to water. We did this in two ways, individual berries and also as whole clusters. The results were almost the same both ways but I will show both. MidSouth, FAMU99, and Conquistador showed a tendency to split when submerged in water overnight. So in this case firmness did not seem to be strongly tied to splitting tendency.

Individual berry splitting of nine grape cultivars.

Percentage of individual berry splitting of nine grape cultivars.

Things were mostly the same when whole clusters were submerged, although there was a little more on Blanc du bois. The difference was small though and with replication and a larger sample size may not be significantly different.

Percentage of berries from whole clusters that split from nine grape cultivars.

Percentage of berries from whole clusters that split from nine grape cultivars.

I was surprised by the lack of splitting from Victoria red. It has what I would characterize as a thinner skin than most of these cultivars, yet it did not split at all. A good thing to know.  Obviously Conquistador has a tendency to split, as ~50% of exposed berries did just that.  Next year we will give it another go-round and see what happens then.

Education and Experimentation via Mississippi Bunch Grapes

And when I say “grape harvest” I mean bunch grapes, not muscadines (which will come later in the season).  This year the vines in my vineyard were in the 3rd leaf.  I harvested a little fruit last year, but this year was the first “big” harvest. Since most of the harvested vines were part of a study, I did various measurements on them (total weight, cluster and berry weights, brix, TA, pH), but had a conundrum — what do I do with the fruit?  The majority of the harvested grapes was from three cultivars: Blanc du bois, Miss blanc, and Villard blanc.  I also harvested a little from MidSouth.  In the end I gave it all away, some of it to folks who helped harvest, but also some to help a business do some experimentation of their own.

Mark and Travis from Lazy Magnolia Brewing Company helping harvest a few vines of Miss blanc

Mark and Travis from Lazy Magnolia Brewing Company helping harvest a few vines of Miss blanc.

Lazy Magnolia Brewing Company is located in Kiln, Mississippi.  Just after I moved here in 2011, my wife and I went for a visit to the brewery where we met Mark Henderson, co-owner. We asked questions about the brewery biz and he asked what we did for a living.  After telling him I worked with grapes, he became very interested and said he wanted to source some local grape juice for a project.  I told him, “good luck” because there was none to be had.  Later, I connected with a local grower, Dr. Wayne Adams, who had some fruit but not enough to supply Mark.  I planted the grape vines as a response to his request. After moving here, I thought my days with grapes was probably over, but what I have found out is there there is a strong interest in Mississippi just like everywhere else. In 2014 I wrote a Specialty Crops Block Grant funded through the Mississippi Department of Agriculture and USDA-NIFA that focused on grape education.  This vineyard helps to bolster that education component.

Fast forward to 2015 and I have vines producing fruit.  I again contacted Mark and asked if he wanted the juice to do some experimenting on.  He said yes.  Unfortunately the Blanc du bois was not in good shape.  It had a good bit of rot caused by early season anthracnose then bunch rots.  The very rainy month of May did it no favors.  However, Miss blanc and Villard blanc were in relatively good shape.

Harvested Miss blanc fruit ready for data measurements

Harvested Miss blanc fruit ready for data measurements.

After getting the fruit in from the field, we took some data measurements then pressed it for juice.  Mark and Travis from Lazy Magnolia came up to help with that process along with my collaborator Dr. Donna Shaw from USDA-ARS in Poplarville.

Dr. Shaw (left) and Mark Henderson (right) pressing Miss blanc grapes for juice

Dr. Shaw (left) and Mark Henderson (right) pressing Miss blanc grapes for juice.

It is a very messy job, but being able to taste the fresh juice is rewarding. Of course it happened to be on one of the hottest days of the year, but then again it is July in South Mississippi!  We were able to get about 20 gallons of juice from 18 Miss blanc vines.  A couple of days later we were able to get 10 gallons of juice from 17 Villard blanc vines.  I also gave Mark about 2 gallons of MidSouth juice (which is acidic but has an intriguing “raspberry” flavor).  So he has between 25-30 gallons to try something (wine, mead, beer, or something else entirely). This project is a beginning to see how Mississippi-grown grapes can be used for marketable products.

If you, or someone you know, is interested in growing bunch grapes in Mississippi please contact me.  Although it is not easy to do, it can be done with the right cultivars and management practices.  Developing markets is another important step in the process, and Lazy Magnolia is exploring whether or not grapes can make a marketable product for their business model with the help of Mississippi State University Extension Service.