Inoculation Day

Last week we talked about using mycorrhizal fungi to improve the health of fruit trees. The fungi are best placed between three and twelve inches below the surface, and either in contact with the roots, or close enough that the roots will find them quickly. So how best to get them there?

When I asked Tammy Kovar how her workers accomplish this for contract jobs, she said they use an auger to bore circular holes, an inch or two in diameter, and fill them with a mix of fungi and soil. That's fine, but augering is not a low-effort pastime. And there's some damage done to the roots, perhaps inconsequential, but I'd prefer not to damage the roots at all if possible.

MRFC Secretary Josh Starry invented a simple but ingenious device to get the job done, as long as there's a good water supply available. A shaft of PVC pipe shoots a jet of water out the end, focused enough to excavate a narrow hole in the soil without actually cutting anything. A valve next to the handle controls the flow, and a bit of experimentation yields a flow rate that works without spewing excess water all over the place.

Here it is in action near one of my citrus trees.

The hole is about 1½ inches across, and as deep as one wants.

Meanwhile, I mixed Tammy's mycorrhizal product with some dry biochar, about 1 part to 4.

Here I am dropping in the mix up to about 3 inches from the surface. I filled the rest with topsoil and Josh watered it all in.

Maybe our efforts will get an extra year or two of fruit out of the struggling citrus, which would be well worth it. The process is fast and easy, and some afternoon we'll do the smaller fruit trees. 

With so many variables in play, it's mighty hard to tell which pampering of our trees has an impact and which is just a waste of time and money. But methods that enrich the ecology rank high in my book.

Going Underground

This story begins last July 11, when Tammy Kovar spoke at our MRFC meeting. I had read about the use of mycorrhizal fungi to stimulate the ecology of plant root zones and provide multiple symbiotic benefits to the host plant. And I had heard about Tammy's Sustainable Landscape Supply company here in Sarasota. But it took her informative presentation and passion for mycorrhizae to spur me into action.

So a few weeks ago I stopped by Sustainable Landscape Supply and purchased 50 pounds of mychorrhizal fungi for my fruit trees. That's a lot, but kept in controlled conditions it will stay alive for three years and that will be plenty of time for me to use it all. Thanks to heavy mulching and other ecologically oriented techniques, most of my fruit trees look very happy, but the multiply challenged citrus trees have been on a long downhill slide. So naturally I'm starting with them.

The challenge with mycorrhizal fungi is to get them growing on the roots of the tree. On healthy soil, most every other fertilizer or soil builder can just be top-dressed around the tree. Over time, the action of rain and the constant nutrient circulation in a healthy ecology will move the tasty stuff underground where the tree's roots will find it. But soil mycorrhizae can't survive exposed to this above-ground nightmare world of UV bombardment and wild temperature swings. They need to be placed on or near the roots. Once in contact with the root system, they will gradually spread and colonize it, and life will be good.

It's easy peasy with new plantings--- at the point when you are loosening the roots from their potbound condition and fluffing them out to help them start into the surrounding soil, just wet them and smear on some of the fine mycorrhizal granules.

Bu when the tree is already established in the ground, it's not so simple. Next week we'll learn about MRFC Secretary Josh Starry's ingenious method, and see photos of it in action.

The Ancient Art

The Tropical Fruit Society of Sarasota meets on the fourth Tuesday of each month, and in October this falls during Eat Local Week. So naturally, we (wearing now my other hat as TFSS Treasurer) have made it an Eat Local Week event and tried to put together an October program that would pique the interest of one-time attendees. This year we hit a home run.

The presenters were longtime TFSS members Nick Ostrye and TFSS Vice President Dr. Tony Hemmer. Each has cultivated the ancient art of winemaking, using tropical fruit instead of those non-local wine grapes.

Tony is a Manatee County resident (that's only turnabout since many MRFC members, including yours truly, grow our fruit down here in Sarasota). He takes a scientific approach to winemaking, and presented the technical basics in a concise powerpoint presentation.

A table displayed an impressive collection of home winemaking gear.

Tony then turned the mic over to Nick, who is more of a traditional "intuitive" winemaker. Like Tony, he's not afraid to try making wine out of almost anything that is sweet and grows on a plant.

Nick emceed the wine tasting. He had procured clear plastic egg cartons and a boatload of little plastic cups that fit perfectly into the compartments.

With their better halves and other volunteers, the speakers had filled the cups with half-ounce servings of ten homemade wines, plus crackers and cheese cubes. A printed insert told what each cup contained.

The duo described each wine in turn, describing the ingredients, sugar content, and special idiosyncrasies of each batch. We sipped exotic flavors like mulberry-jaboticaba, with many tints and levels of sweetness.

Ten rounds later we were all impressed with the variety and quality of the home brews. Ten half-ounces only add up to one glass of wine, but the crowd left in an especially cheery mood. I've stashed the leftover cartons and cups for a repeat performance down the road.

The Great Banana Flower Controversy

Here at MRFC Articles we don't shy away from the great issues of the day. We're going to look at the question of when to remove the male flower--- the big red bud at the end of the fruiting stalk--- from a forming bunch of bananas.

A 2014 thread at the Tropical Fruit Forum discussion board delved into this question. The most common reason cited for removal of the flower was to let the plant put its energy into the fruit rather than maintaining the flower. According to several posters, this has been tested in multiple controlled studies. Some show no effect, others a slight increase in the weight of the banana bunch--- negligible in comparison with the effects of proper watering, fertilization, and so on.

A second reason given for flower removal is that stalks often break or fall over under the increasing weight of the fruit, ruining the lot of them, and the couple of pounds or so that the flower adds is a useless additional burden. An answer to this is that if the stalk is really in any danger of collapse, one should prop it up with a couple of long poles tied together in an "X", or build a support out of PVC pipe, or otherwise rig up some support to prevent it.

Yet another reason, for commercial growers, is that when the flower is removed, a fair amount of sticky sap pours out of the stem. Added to the unavoidable seepage from the stalk end, this is more than a minor annoyance when you're harvesting hundreds of bunches in a day. So better to lop off the flower ahead of time, allowing the cut to seal by harvest time.

Some posters mentioned that the banana flower is edible. Though it's not a common practice in this country, in Asia they are often eaten and considered quite tasty by those who know how to prepare and cook them properly.

Why would you not want to remove the flower? There are reports of fungus gaining a foothold at the cut and working its way into the stem. If it really doesn't make any difference otherwise, why risk this?

The bottom line is that for the home grower, at least, it doesn't much matter. If you like the look of flower buds on your banana stalks, by all means leave them there. And it may be worth looking up how to cook them and giving it a try, you might love them.

Bananas 101

For a couple of weeks we'll be talking about bananas. Next time we'll look at the question of whether to remove the banana flower once the fruit has formed. For now, let's make sure everyone has seen the basics about banana plants.

The first thing to know is that there is no such thing as a banana tree--- banana plants contain no wood. They consist of a tuberlike underground stem, called a corm, and individual stalks that emerge from it. Each stalk will flower and fruit only once, and then should be removed. Indeed, once the plant is well established, you can whack off stems without hurting it a bit. An often-recommended approach is to allow only three stems at a time: a full-sized one, a partially grown one, and a small one. This forces the plant to put all of its energy into fruiting on one stalk at a time.

Remove young stems by chopping them off the corm with a sharp-edged shovel, as cutting them at ground level just lets them keep growing. Allow a stem to grow only if it shoots up close to a big stalk and puts out just a few narrow leaves at first. These are "spears" growing directly from the corm and drawing on its stored energy. The smaller new stems that leaf out more, and are usually farther from the big stalks, are starting more-or-less from scratch, and will take much longer to grow and fruit. These should go in the compost, but spears can easily be potted up or just directly planted to make a new banana plant.

If you've never seen a banana plant forming fruit, it's like something from another planet. Each stalk puts out one large leaf at a time as it grows, keeping the last five to ten leaves as older ones wilt. After about 35 leaves, a single large deep red bud emerges on a leafless central stem. As the stem lengthens, little hands of tiny bananas are formed just behind the bud. Eventually this process stops, and the bananas grow in size until you or the squirrels decide they are ready to harvest.

The bud is generally called the banana flower, but it's really a housing for the male flowers that are exposed as leaves curl off the bud. The tiny female flowers that actually become the bananas are on the stalk itself. After the formation, the bud just sits there at the end of the stalk as the bananas grow and ripen. Many folks, including commercial growers, cut the flower off once the fruits are formed, but others leave them on. Next time, we'll look at the arguments on both sides of this grand controversy.

EBP FAQ

I expect to make several posts about the East Bradenton Park Fruit Tree Grove project in upcoming months. A good way to start might be with the current draft of our FAQ. Amber Mills, Public Health Specialist of the Florida Department of Health in Manatee County, provided many helpful edits to my first draft. Amber has spearheaded the East Bradenton Park revitalization project, and it has been a pleasure to work with her and all of those involved in it.

Who planted the grove?

The grove is a joint project involving the Florida Department of Health in Manatee County, the Manatee County Government, the Manatee Rare Fruit Council, the Tropical Fruit Society of Sarasota and the UF/IFAS Extensions of Manatee and Sarasota County.

Why a fruit tree grove?

In Manatee County, survey results to assess interventions for healthy food access and consumption evaluated access to fruit trees, gardening and educational opportunities, farm stands, and lower costs. According to assessment findings, the East Bradenton community perceived fresh fruits and vegetables to be expensive, and found the time it takes to obtain and prepare them to be a barrier to consuming healthy food. The fruit tree orchard in the East Bradenton Park will provide inexpensive access to fruits as well as increase the availability of locally grown food for its community members.

How can it help the community?

There are several benefits. The East Bradenton Park neighborhood is a designated food desert, with insufficient fresh produce available. When the trees start to produce fruit, it will be freely available to area residents for their personal consumption (not for resale). When the 21 trees reach full production size, this will be a considerable amount of food. More importantly, the grove will provide both knowledge and inspiration for area residents to grow more of their own fruit in backyards and other available areas. If not just 21, but several hundred productive fruit trees can be established in the neighborhood, a tremendous amount of fruit can be produced for consumption, trade, or income. Finally, we hope that this beautiful grove will be a model for other such projects, and that the residents of the community will take pride in being the leader in this initiative.

When will there be fruit to eat?

A fruit tree planted as a seed will usually take 5 to 10 years before it begins to produce, and the resulting fruit might not be high quality. However, the trees in the East Bradenton Park grove are grafted trees, which will yield high-quality fruit as soon as they are large enough. How soon will depend on the kind of tree. Some, like the starfruit, bananas, and papaya, might produce within a year. Most will take two or three years, and a few, like the avocados, may take four years. Don't be shocked to see some of the experts who are initially maintaining the grove remove the fruit from some of the trees before it is ripe. In those cases, the tree is too small to produce good fruit, and needs another year or two of growth before fruiting. Without the burden of producing fruit, the young tree will grow much faster, and will produce far more in the long run.

How were these trees selected?

Experts from the UF/IFAS Extension Office and members of area fruit tree clubs worked together to make the selection, based on several considerations. All of these trees will grow very well in our area, and can be very productive without spraying pesticides or using expensive fertilizers. They produce fruit in different seasons, so eventually there should be at least some fruit almost any day of the year. Finally, the trees provide options for many situations: some do well in wetter soils, others in drier, some will get large and others will stay fairly small, and so on. Most any space with some sunlight and soil can be a home for at least one of these types of trees.

Who will take care of the trees?

Fruit trees like these, that are well adapted to our area, do not require much care. Initially, volunteers from the local fruit tree clubs will tend to the grove. As time goes on, local residents can take “ownership” of this responsibility. Those who are interested but do not have experience can learn through many sources: either directly from the volunteers (feel free to ask them questions, or just say hi), through self-study, by joining local fruit tree clubs that have monthly meetings to share knowledge and information, and finally through local volunteers who provide one-day classes in all the basics.

The Magnificent Five and Two Halves

The rains onto saturated soil continued into early autumn, dropping another of my Sunrise papayas. It got the same makeover as its mate. New growth is already bursting forth from that first tipsy survivor.

The bigger news is that we're now eating our own papayas. Considering that the Magnificent Seven went in the ground on March 1 after starting from seed last year, this qualifies as instant gratification on the fruit-tree time scale.

The Sunrise produce very small fruits, ironic enough given the size and vigor of the plant. The Queen of the Indoors loves them, and indeed they are fine-tasting. It will be interesting to see how the topped-off plants fruit next year and how their productivity is affected.

I was more curious about the broadleaf papayas.  As you can see here, the fruit is much larger than the hand-size Sunrise's.

After the hefty fruit ripened to yellow with just a hint of green remaining, the flesh was a beautiful deep orange. But after all the hype, the taste was disappointing. There seemed to be an edge to the flavor not present in the smooth-tasting Sunrises. I found them good enough to eat, but the Queen said to call back when there were more Sunrise's. We'll see how the fruit of these two varieties evolves as the plants age, and whether dry-season product tastes different.

Meanwhile the two Costa Ricans are loaded with large fruits. I can hardly wait to see what it's like.