DOING SOMETHING ABOUT (MICRO)CLIMATE CHANGE

Microclimates, Here, There, and Everywhere

    Mark Twain wrote that “Everyone complains about the weather but nobody does anything about it.” I’m going to step up to the plate and do something about it — not the climate but the microclimate. “Microclimate” is the very local weather. And I do mean “very local,” as, for example, right around a particular plant.
    Different microclimates exist all around my property — and yours. Near the south wall of my brick house for example, winter low temperatures don’t plummet nearly as low as they do, say, 30 feet away from the wall. The bricks are very good at absorbing the sun’s heat, then let it slowly ooze out after nightfall. Near that wall is where I’m planning to plant out a Kadota fig tree now dormant in my basement. (Come late fall, after harvest, I’ll dig up the tree with a good root ball and return it to winter quarters in the basement.) 

'Surround', a white clay, sprayed on apples

‘Surround’, a white clay, sprayed on apples

    On the other side of my house, where sunlight can’t fall in winter, days and nights are colder than the general temperatures, and remain colder from spring through fall. Near that north wall, then, would be a good place to plant an apricot or peach tree to delay unfolding of their blossoms, which otherwise open so early that they often succumb to subsequent spring frosts. Dead blossoms mean no crop for that season.
    Apricots and peaches, like most fruits need sunlight to fuel the most flavorful fruits. Although areas near the north wall are shaded — and hence cooler — in winter, from spring through early fall the sun wraps enough around the sky from the northeast to northwest corners to cast its light there.
    Other influences on microclimate include fences, land sloping in various directions, paved areas, plant or built windbreaks, and changes in elevation.

(Micro)Climate Modification

    Much of what I have planted, including many fruit plants, are nowhere near fences or paving, and my land is mostly flat. It is lowland, in a valley, and cold air, which is heavier than warm air, collects in this low spots, to threaten the blossoms on my fruit plants with late, killing frosts.
    Mark Twain notwithstanding, I’m going to try doing something about the weather — the microclimate, in this case — on plants nowhere near walls, fences, or paving.
    Enter ‘Surround’, the trademark name for a special formulation of kaolin clay. This product was developed about 30 years ago mostly as a nontoxic way to thwart insect pests. It’s especially useful for controlling plum curculio, a pest of plums, peaches, apples, and some other fruits; curculio isn’t easily controlled by other organic methods.
 

'Surround'  spray on blueberries

‘Surround’ spray on blueberries

   Kaolin is white, so when a sufficiently thick coating of ‘Surround’ is built up on branches, they appear white. Old Sol’s rays just bounce off white surfaces, the surfaces, in this case being the buds of fruit plants. So the buds stay cooler, delaying bloom, hopefully until after threat of frost has past.
    I’ve already given the plant a couple of coats of ‘Surround’, and they already have a sun-drenched, gray-cast, Mediterranean look to them. A couple more coats will make the visual effect more dramatic, both to me and Ol’ Sol, and will get a jump on curculio control.

Awake too Soon

    Downstairs, in the basement, things are not as quiescent as hoped. That’s where the figs, pomegranates, and mulberries are spending winter, the cool (45°F) temperature holding back growth. Or so I thought.
    One plant, Pakistan mulberry, has decided to awaken. This mulberry is a species of white mulberry (Morus alba) that differs markedly from the white mulberries you see here. Pakistan is only about as cold-hardy as fig (which is why they share winter quarters in my basement) and bears a very delicious, dark purple fruit up to three inches long!

'Pakistan' mulberry

‘Pakistan’ mulberry

    Pakistan evidently has a low chill requirement, that is, it does not take much cold for it to feel like winter has ended so it can begin growing. Different plants have different requirements for the number of hours of chilling, which is temperatures between about 30 and 45°F., they need to be exposed to before they can begin growth for the season.
    I may have to move the budding plant into the greenhouse where it really is spring, with temperatures at least into the 70s on this sunny day.

LITTLE ITALY IN THE HUDSON VALLEY

 Curing my Olive Harvest

   My olive harvest, about which I recently wrote, was such a success that I want to up my production beyond this year’s bountiful 6 fruits. Those 6 fruits, once cured, were truly delicious. (Yes, the halo effect — my assessment of them veiled by my having grown them — could come into play.)
    Part of the reason for the fruits’ high quality was how I cured them. Not very complicated: I just let them sit and dry out. After about two weeks, they had lost their bitterness, and, without the distraction of salt, oil, or spices, their rich, olive flavor shined through.

New Roots, New Shoots

    Part one of my twofold plan to increase production is to put the plant into a larger pot. A larger pot makes for a larger plant; a larger plant has more branches on which to hang more fruit.
    Looking more closely at the plant told me that re-potting was necessary immediately! New flower buds are already beginning for the next crop. Because the plant is moving up to a larger pot, no root pruning is necessary. I put some potting soil in the bottom of a pot, set the exposed root ball on top of the soil, loosened some roots along the outside of the root ball, and packed new soil in the space between the root ball the the side of the pot.My potted olive tree, pruned
    With soil firmed and a thorough watering, the roots have a happy home — for a year or two, when root pruning and re-potting become necessary. If moved up to a yet larger pot, the plant would be too unwieldy to muscle indoors and out.
    Part two of my plan to increase production is pruning. To prune any fruit plant for best yield and quality, you  have to know something about how the particular plant bears its fruits. For instance, peaches are pruned very differently from apples because peaches bear only on one-year-old wood and apples bear on wood a couple of years old on up to a decade or older. One of the goals in pruning peaches is to coax enough new growth this year for a good crop next year.
    To figure out how to best prune an olive, I referred back to The Pruning Book (which I wrote, and also details pruning of apples, peaches, and just about every other plant). “Fruits form in leaf axils along, but not to the end of, the previous year’s stems (and sometimes from dormant buds in one- or two-year-old wood).”
    So olive fruits something like a peach, on young wood. Actually more like an apricot, which bears fruit on wood from one to three years old.
    My ploy was too shorten some stems, focussing on those making the plant look gawky. Without sacrificing yield, shortening stems has the benefit of encouraging new, branching growth. More branching will make the plant look prettier and provide more young stems on which to hang fruit next year.

Sleep, Sweet Fig

    Going from the sun-drenched window, in front of which my olive tree basks, all the way down to the basement, I check out another Mediterranean fruit, my potted fig trees. What’s happening with them? Nothing, I hope.
    Now is a crucial time of year for a potted fig tree. The goal is to keep them dormant. Unfortunately, just a bit more warmth or a bit more light and they’ll start to awaken. If awakened, new growth will be soft and sappy, even if the plants sit in front of a sunny window. Then, when the plants finally go outdoors, intense sunlight, wind, and cooler temperatures are apt to burn back such growth.
  Figs buds, still dormant in basement  Temperatures stay relatively consistent and cool (40-45°F.) in my basement and it’s dark down there, so the plants generally stay dormant until sometime, probably next month, when I can set them outside. Keeping the plants slightly on the dry side also helps hold back growth.
    Last year was perfect. I moved the dormant figs outdoors while the weather was still cool without temperatures dropping too low below freezing. (Dormant figs tolerate temperatures down to the low 20s.) Growth began in synch with increasing temperatures, culminating in branches draped with soft, ripe figs by summer’s end. I’m planning for a repeat performance.

MYSTERY OF THE UNDEAD ROSE

 Death shows Life

   It was with red rose in hand — a long-stemmed red rose — that Deb returned from a recent bridal shower. The rose was a party favor, the flower a welcome sight in the dead of winter. It found a home in a vase of water on the kitchen table.
    After a week, the rose was still sitting on the kitchen table, its bloom looking as perky as the day it had arrived. After two weeks, still no change.
    Okay, I’m sure that the vase was clean, the water fresh and initially warm (for quicker absorption into the stem), and that the base of the stem was freshly cut at a 45 degree angle just before immersion. All that, and the cool room, would make the blossom last longer. But that long?

Commercial rose, after 2 weeks

Commercial rose, after 2 weeks

    No special potions were added to the water. Like sugar, to feed the leafless stem and flower. Or an acidifier to make the water’s acidity more near that of the cell sap, stabilizing the flower’s color. Or an inhibitor to prevent microbes from running amuck. Such potions can be purchased or made at home by mixing: 1 teaspoon of sugar, 1 teaspoon of plain household bleach, 2 teaspoons of lemon or lime juice and a quart of lukewarm water; or mixing 2 parts water to 1 part tonic water (or non-diet lemon lime soda).
    The problem was that the blossom was eerily too alive after a couple weeks. Without roots, sunshine, or leaves, the flower should have started dropping petals and looking generally forlorn. It didn’t, at least not quickly enough to exude that there was a life force within.
    Contrast this behavior with that of the carnations (Dianthus caryophyllus) that blossom sporadically in my greenhouse through winter.  I cut the fragrant, pink blossoms, put them in a vase of water, and within a week they’re spent.
    I’ve gained appreciation for the transience of cut blossoms. Their timely decline and death declare their aliveness.

Blame it on (a) Gas

    Comparing roses and carnations may be like comparing apples and oranges.
    Ethylene, a simple gas that’s also a potent plant hormone, comes into play here for its role in plant senescence, including that of cut flowers. Combustion, whether from a cigarette, an automobile engine, or a candle, produces some ethylene, as do plants themselves, especially when they are wounded or in their final throes of aging.
 Carnation, fragrant and pretty   Carnations are among flowers, along with baby’s-breath, lilies, snapdragons, and most orchids, whose ethylene production ramps up as senescence begins. These flowers also are very sensitive to the effects of ethylene, which speeds aging, which generates more ethylene, which further speeds aging, which . . .
    Roses, in contrast, are less sensitive to ethylene. (And ethylene plays no role in the decline of daisies, daffodils, and irises.) Also, as a commercial product, the long-stemmed, red rose that sat on my kitchen table could have been pre-treated with silver thiosulfate or aminoethoxyvinylglycine, both ethylene inhibitors.
    No matter. I don’t require a whole lot of carnation blossoms, and new ones appear at a rate sufficient to replace spent ones, or, if slower, to increase appreciation for each new one.

In the Greenhouse, Out with the Old, In with the New

    All winter, the greenhouse beds have been vibrant green with lettuce, arugula, celery, parsley, mâche, chard, kale, and claytonia. Just lately, the greenery has lost some of its vibrance.Lettuce going to seed
    Planted in early fall, these greens grew to size — as hoped — to provide good eating through winter. Over the past few weeks, as days grew short and dim, and temperatures cooled, the greenery — as expected — mostly just sat still. In anticipation, I had grown them to size before the onset of winter. A bigger greenhouse would allow for a little something to be harvested from a lot of little, slow growing plants, enough for the daily fare. But the greenhouse is what it is.
    And some of the lettuce plants, though not very big or old, are going to seed. It seems that lettuce transplants, rather than plants from seeds planted right in the ground, are more prone to this bolting.
    Time for some fresh young growth: I pulled out some old and bolting plants, and sowed fresh lettuce, spinach, and arugula seeds. Growth will be slow for now; older plants should supply sufficient harvest until young’uns are ready for picking.