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TOTIPOTENT — NOT WHAT IT SOUNDS LIKE

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 Cells Beget Plants, or Animals

   As I strode out to the garden today, the word “totipotency” was forefront in my mind. No, I wasn’t thinking of myself as “all powerful,” which is what totipotent (Latin totus=whole, potent=powerful) might seem to mean.
    Totipotency is the ability of any cell in an organism — you, me, my dog Sammy, my rose bush — to potentially give rise to any other kind of cell of that organism, or to a whole new organism, a clone of the original. Under the right conditions, you could put one of your skin cells in the right environment, and have those cells grow into new skin, toes, eyes — even a whole new you. Fortunately, nobody has yet figured out how to do that with a human.
    (What I wrote is not exactly true. Not every cell within an organism is totipotent. In organisms that reproduce sexually, egg and sperm cells — the germ cells — have only half their complement of genes, so these particular cells can’t be cloned to reproduce non-germ cells or whole organisms.)
    Back to the garden and totipotence . . . Using random plant parts to make whole new plants is nothing new to most gardeners. With stem cuttings, for example, you put a stem into a suitable environment, and it’s induced to grow roots at its base and new shoots, followed by flowers and, perhaps, fruits, above ground. With leaf cuttings, all these new parts spring from a mere leaf.
    Stems and leaves are more than just a few cells. More specialized, but still feasible, is cloning with just a few cells: so-called micropropagation or tissue culture. A few cells are removed, usually from a growing point, and then, under sterile conditions, put into a petri dish containing a medium to supply nutrients and a balance of plant growth hormones. The cells multiply without differentiation into anything special until they are transferred to another medium, this one with an altered balance of hormones, that induces cells to differentiate into leaves and roots. After a period of growth, the plantlets graduate to real soil.
    Micropropagation is a way to create many new, pest-free clones quickly and from a minimum of amount of mother plant.

Apolitical Graft

    My foray into “totipotencing” plants today required pretty much nothing more than pruning shears. I was cutting scion wood, which are stems for grafting onto growing plants. In this case, the growing plants — the rootstocks — provide roots to the clone; the completed plant, from the graft upwards, is the clone, in this case various varieties of pears.

Watersprouts on old apple tree

Watersprouts on old apple tree

    In the past, I’ve done a “Henry IVth” on pear trees whose fruits were not up to snuff, then grafted a more desirable scion on to the decapitated trees. Today’s scions are for grafting onto one-year-old pear seedlings, to make new pear trees. (Not that I need that many pear trees. The grafting will be done by participants at a couple of grafting workshops I’ll be holding this spring. Stay tuned to my website for when, where, and other details.)
    Grafts are most successful with young scions — one-year-old stems, those that grew last season. They come in various sizes, depending on their vigor; pencil-thick is about right. I cut them into foot-long lengths. Watersprouts, those vigorous, vertical branches often appearing in the upper parts of a tree, are good for scionwood, and most, anyway, should be removed.
 

Pear scions

Pear scions

  The odds for success are also increased if grafting takes place with dormant scions grafted on rootstocks that are either dormant or awakening. That’s why I collected scions today; they’re still dormant, but not for long, outdoors.
    I’ll keep those scions dormant with cold, in the refrigerator or my mudroom (north side of the house, tile floor over concrete).
    Drying out would spell death to the scions, as it would to any living plant or plant part. They need to be kept hydrated, but not in so moist an environment as to cause rotting. So I store them in a plastic bag, around which I wrap a moist towel, and then put the towel-wrapped bag into another plastic bag, well-sealed.

I Was Wrong About Arnold

    I was wrong. Back in December, I wrote, “My Arnold’s Promise witchhazel usually flowers in March. This year’s October flowering means no flowers this coming spring.” Well, it’s March 1st as I write this, and Arnold’s Promise is showered with strappy, yellow blossoms.

Witchhazel's winter flowers and remains of fall flowers

Witchhazel’s winter flowers and remains of fall flowers

    Evidently, not all flower buds slated to open this month opened prematurely, last October. Some did as they are supposed to do: waited. Why? Good question. Looking at the shrub, a location effect does not seem to come into play. Late winter blossoms seem randomly distributed rather than concentrated on older, younger, lower, higher, southern, or northern stems.
    With no explanation coming to mind (yet!), I’ll just relax and enjoy the unexpected show.

Beans, Beans, . . . and Blueberries

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Deb and David gather around the kitchen table as the contenders are brought forth, each steeped in its own cooking juice in a custard cup. The event is the long-awaited bean test, home-grown Cannellini beans vs. store-bought Cannellini beans vs. home-grown Calypso (Yin Yang) beans. Mostly, we are interested in

whether the home-grown Cannellini’s would be better than the store bought, a possible reason being that stored, dry beans get tougher with age.

I planted a very short row of the Cannellini and of Calypso beans back in the middle of May. I do mean short, only about 5 feet each. After all, this planting was for testing, not for production.
The beans I planted, as well as kidney beans, pinto beans, and some other dry beans, and green beans, share the same botanical lineage, Phaseolus vulgaris. All can be grown just like green beans except that for dry beans, the harvest is of mature seeds, so a longer season is required, typically around 90 days or so.
After my dry bean harvest, I transferred an aliquot of each variety into its own glass custard cup, did the same with an aliquot of store-bought Cannellini beans, and filled the custard cups with water. The cups went into a larger pot with an inch of water and the whole setup went onto the woodstove to simmer for a couple of days. Retrieval and cooling bring us to this moment.
No need for a blindfold test because the differences were dramatic. The results? All three of us gave the home-grown Cannellini’s the highest marks in terms of creamy texture and good flavor. Second best was Calypso. It appears that I’ll be devoting more space next year to growing Cannellini beans.
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In addition to mouth-watering flavor and creamy texture, Cannellini beans (and other white beans) are rich in phosphatidylserine. The thinnest thread of evidence suggests that phosphatidylserine might — just might — improve memory and cognition, as well as confer other health benefits. Cow brains are among the richest sources of phosphatidylserine, but I’d rather be forgetful than get mad cow disease.
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Lowbush blueberries abound in the woods around here but are conspicuously absent from gardens and landscapes — except in my front yard. I grow them for “luscious landscaping,” that is, for both beauty and

good eating. Plants recently shed their crimson leaves, which is how they show off in autumn. In spring, they show off their nodding, bell-shaped, white flowers, and all summer long, the ground is blanketed with healthy, bluish-green leaves on stems a foot and a half high.

Next summer, I know my plants won’t fruit because yesterday I cut all the stems right down to the ground. Best yields come from stems that are one-year-old and two-years-old, so stems have to grow at least a year before they can flower and fruit.
Traditionally, and under natural conditions, periodic pruning of lowbush blueberries was done with fire. Fire had the additional advantage of knocking out some potential weed and pest problems. Of course, burning also has its hazards and I’m not seeking any excitement in the blueberry bed along the east side of my house beyond a big crop of berries. So I went at the plants this week with hedge shears and hand shears, cutting the stems as low as possible. The lower to the ground plants are lopped back, the fewer the resulting stems next summer, and the more energy the plants can channel into fruit buds for the following year’s harvest.
I don’t really want to sacrifice all of next year’s lowbush blueberry crop so I lopped to the ground only half the planting. Next year, that half that was spared my shears will bear and next autumn I’ll cut those stems down. The summer after next, this year’s lopped down plants will bear fruit, and next year’s lopped down plants won’t. And so the harvest can continue hopscotching merrily along, keeping the plants productive and me in berries every year.
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Sharing the lowbush blueberry bed is an Arnold’s Promise witchhazel shrub getting its digs in to offer what is perhaps the final oddity for a generally odd growing season. Year after year it has reliably flowered in March. This year it’s flowering right now, probably because of cool weather followed by extended warm weather duping the shrub into acting as if it was, in fact, March.
One problem with November flowering is that fewer or no flowers will open this coming March. Another problem is that I’d rather see the flowers in March, coming in other heels of winter’s relatively achromatic landscape.