Thursday, May 30, 2013

It (Could Be) Cold

I see a lot of gardens under wraps this morning, plants covered with upturned buckets or flowerpots, or blanketed under . . . well . . . blankets. Day after day of balmy temperatures have made it hard to hold back finally getting vegetable and flower transplants out of their pots and into the ground.

But temperatures just below freezing were predicted for last night (May 13th) and everyone got a wakeup call: Freezing temperatures, which could kill tomato, marigold, and other tender plants, are still possible. It’s all about averages; around here, there’s about a 10 percent chance of a frost the middle of May.

The likelihood of cold, frosty, or freezing temperatures has been detailed -- see -- for locations throughout the country. The closest weather station connected to that site around here is in Poughkeepsie, and in mid-May that site has a 50% chance of experiencing cold weather (36°F.) and a 10% chance of of experiencing frost (32°F.). Cold air, being heavier than warm air, sinks to low-lying spots on clear still nights, such as last night, so my garden in the Wallkill River valley is usually a few degrees colder than surrounding areas, such as Poughkeepsie. Fortunately, temperatures last night here dropped only to 31° F.

Not that lower temperatures would have done my vegetables or flowers any harm. I took the advice I’ve been doling out to others for the past couple of (warm) weeks, and held off planting anything that could be harmed by frost. So tomatoes, peppers, melons, and the like are still in pots that I moved into the warmth of the greenhouse last night.

I’d like to plant out all these cold-tender seedlings but chilly temperatures are predicted for the next few night. Even chilly temperatures, let alone freezing temperatures, are not good for tender plants.

Still, anyone looking out over my garden this morning would have seen white blankets over some beds and overturned flowerpots over a few plants. Because my garden is in a cold spot, temperatures well below freezing were not out of the question for last night. Cold enough temperatures could damage cabbage and its
kin, lettuce, onions, and other cold-hardy transplants that have been growing out in the garden for the past couple of weeks. I had some row cover material readily on hand, so why not, methought, throw it over some of the beds anyway? Just in case.
Throwing covers over plants at 7 in the evening is a lot more pleasant than waking up at 3 am with the sinking feeling that temperatures have really plummeted and then, if they in fact did, running outdoors in the cold darkness to cover plants.

Fruit trees, shrubs, and vines present another story. A freeze won’t kill the plants, but low enough temperatures could kill flowers or developing fruit, as it did on many fruit plants last year. One frigid night and you have to wait a whole year for the next crop. Unfortunately, not much could be done about this situation. Fruit plants here are too many or too big to cover. My tack is to keep fingers crossed.

Critical temperatures for fruit damage vary with the kind of fruit, the stage of flower or fruit development, the depth of cold, and the duration of cold. Probably other things, too, such as humidity and plant nutrition. 

An excellent table of “Critical Temperatures for Frost Damage on Fruit Trees” can be viewed at So, put simply, 25°F would spell death to 90% of my apples, which are in full bloom, and pears, which are post-bloom, and 28% would do in 10% of their fruits. Plums, also post-bloom, tolerate a bit more cold.

In addition to crossing fingers, my tack is also to grow a variety of fruits, and especially native fruits.
Pawpaw blossom, from below.
(Apples, pears, peaches, and most plums are not native.) It’s not a chauvinistic choice; it’s just that these natives -- American persimmon, pawpaw, blueberry, grape, and gooseberry, to name a few -- are better adapted to our conditions. And not just the weather here. Pests also.

This spring has been the most perfect spring in a long time, with plenty of clear, sunny days and gradually warming temperatures that kept blossoms from jumping the gun. Playing the averages, the critical cold periods should be pretty much be behind us. As with the stock market, though, “Past performance is no guarantee of future returns.”
Update, May 17th: Warm days and nights that are not too chilly are predicted for the next few days, so I planted out tomatoes and peppers today. I’ll still keep an eye on temperatures because there’s still a 10% chance of temperatures dipping to 36° as late as May 28th according to records at the nearby Poughkeepsie weather monitoring station.

Thursday, May 23, 2013

Compost and Cucurbits

You’d think, this time of year, that all I’d be doing is sowing seeds and transplanting small and large plants. I am. But I’m also turning compost piles, getting ready to use that “black gold” this autumn. Why now? So the stuff has time to mellow and to make space for new compost piles that will be built from now through autumn.

Here’s my compost routine: All summer and into autumn I fill empty compost bins with hay, wood shavings, horse manure, weeds, kitchen waste, and old garden plants along with some sprinklings of soil, limestone, soybean meal (if extra nitrogen is needed), and sufficient water to moisten the ingredients. When a bin is full, which means loaded up about 5 feet high, it gets covered with a sheet of EPDM rubber roofing material to keep excess moisture out and to seal in whatever moisture is within. A numbered label on each pile gets recorded to remind me when the pile was completed, what went in, and, with the help of a 2-foot-long thermometer, how much heat, if any, was generated.

Fast forward to today. I’m flipping over the contents of two compost bins, one completed last July and the other last August, into empty adjacent bins. Turning over the contents lets me see how the compost
has fared over the past 10 months; some piles might still be a bit raw, others are just about finished and ready for use. No matter, I don’t need any compost yet.

No rule that says compost piles have to be turned at all. I do it because I like to see what’s been going on and so I can make slight adjustments, as needed.  Sometimes a little more water is needed. Turning the pile also gives me the opportunity to break up any clumps of material and render the finished pile more uniform.

One of the piles I turned this spring had so much undecomposed hay in it that I sprinkled on some soybean meal as I turned it. Even that wasn’t one-hundred percent necessary; the high nitrogen soybean meal just speeds decomposition. Leave any organic materials (that is, something that is or was living) piled together long enough, with a bit of moisture, and it will definitely turn to compost. As my bumper sticker reads: “Compost happens.”

One more reason for turning and organizing all of last year’s compost piles is to make space for growing melons and squashes. My vegetable garden is very intensively planted, with 3 foot wide beds packed tight with one or more vegetables growing together or in sequence, perhaps even trained skyward to get more out of the space. The long, sprawling vines of melons and squashes don’t fit into this scheme of things.

The compost bins -- 4 foot by four foot by 3 to 4 foot high cubes --  are perfect for these vines. Three or 4 plants poked into the rich compost through holes made in the rubber roofing can sprawl to their hearts’ content, spreading out to cover the tops of the bins and then, if they like, draping down to the ground, even creeping along the ground if that’s their whim. 
Melons and squashes thrive in rich soil, and my plants roots couldn’t find themselves in a richer soil than the pure compost within the bins. Plenty of water is needed to plump up the fruits; the compost clings to enough water so that watering is hardly necessary.

The only melon that does not get planted on a compost bin is watermelon. But even watermelon doesn’t go in the garden. It goes onto a pile of wood chips or leaves I had dumped here last autumn and winter.

In contrast to the muskmelons, honeydews, and cantaloupes, all which bear a few fruits and then give up the ship, watermelon vines just keep bearing and bearing until stopped by frost or short days. I’ll
need to get into the compost bins before frost and short days; muskmelons, honeydews, and cantaloupes will be gone and out of the way but watermelon would not.

Also, watermelons don’t demand a rich soil. “Soil” that’s either partially decomposed leaves or wood chips is poor in nutrients, to say the least. So poor that when I plant in the leaf or wood chip pile, I scoop out a generous hole and fill it with compost to get the plant off to a good start. During the growing season, I’ll occasionally dose the watermelon plants with some soluble fertilizer.

All kinds of melons thrive in heat, in the air and in the ground. Freshly turned compost and old leaves or wood chips aren’t static. They are decomposing and, in doing so, generating some heat. All of which makes for good crops of good-tasting melons.

Saturday, May 18, 2013

Deferred Gratification

If there’s one thing I don’t like about gardening, it’s all the deferred gratification, all  the looking to the future. That future might be 3 or 4 weeks hence, when I’m planning to start harvesting the radishes that I’ll be sowing today. Or 8 or 9 weeks hence, when I’ll start harvesting tomatoes from plants I’m nurturing today and that I sowed in early April for planting out towards the end of May.

And it doesn’t end. No sooner will a large portion of the seeds and transplants be snuggled into this season’s garden than I’ll be sowing seeds of cabbage and broccoli for eventual transplanting in midsummer for harvest in autumn. Planning for autumn now! Shudder the thought, but it’s got to be done. I don’t want to even think about autumn’s impending cold weather with this wonderfully warming spring weather.

Okay, let me take a deep breath and resolve this not-living-in-the-present of gardening. It’s not really that bad. I figure out what has to be done -- a written schedule updated as necessary from previous seasons’ notes is crucial for this -- and and then immerse myself in the all-present of doing it. And it’s not all for end results; there’s the joy and satisfaction of watching plants grow and come into fruition and respond to my ministrations.

In some cases, the longer the period of deferred gratification, the greater the satisfaction.

I wrote back in February about the excitement of seeing white roots of some yellowhorn tree seeds that were sprouting in potting soil in a plastic bag in my refrigerator. I planted all those in pots. But also, in that plastic bag, were some hackberry seeds I had collected last autumn. They were doing nothing. Nothing obvious, that is.

Seeds of woody plants that ripen in autumn have a dormancy that lasts until they think winter is over. Winter for my hackberry and yellowhorn seeds takes place in my refrigerator, which is ideal because the
temperatures that spur seeds -- and plant growth, for that matter -- awake are between about 30 and 45°F. That’s why yellowhorn seeds awoke back in February. Outdoors, the requisite number of hours in that temperature range might not have accumulated until around now.

Hackberry seeds evidently need to experience more chilly hours before they’re convinced to wake up, which happened last week. I potted up the delicate little seedlings.

In 20 years or so, those six hackberry seedlings should be large enough to be clothed in a corky bark that, especially in winter, displays crisp, achromatic
shadows reminiscent of the lunar landscape. Perhaps by then the plants will be old enough to bear pea-sized, date-flavored fruits. Not that the fruits offer much more than a nibble; within each pea-sized fruit is an almost pea-sized seed, leaving just a thin covering of sweet flesh.

Sometimes -- usually -- it’s best to let Mother Nature do the planting. On a recent drive to West Virginia, where the spring season is about a week ahead of here, the mountainsides were awash in redbud bloom.

Usually, I not a fan of redbud. It’s the color. Pinkish purple. Yuk, and too flamboyant. At least, to me, from isolated trees that blare out their color from front or back yards.

But isolated redbud trees as well as large swathes of them livened up the scene as they nestled in among forests of trees
unfolding soft-colored, pale green blossoms and young leaves.

On a shorter time scale, I see Ms. Nature has also done a nice planting of cilantro. In the couple of beds where cilantro stood last year (from self-sown seeds of the previous year), small plants are now ready for harvest. And I didn’t even have to think ahead to plant them.

Friday, May 10, 2013

Rational in Spring? No.

People are funny, and that includes gardeners. Gardening is basically simple: You put a seed in the ground and, backed by millions of years of evolution, that seed grows. Sure, there are a few more wrinkles, like choosing a sunny spot (for sun loving plants), a well-drained soil (except for bog and water plants), and enriching the ground with organic materials, and, perhaps, fertilizer.

But people love to complicate things. Hence, compost tea, biochar, and now, straw bale culture. A recent article in the New York Times about straw bale culture has everyone -- or at least the handful of people who told me of their plans for the season -- trying out this new and allegedly wonderful alternative to merely dropping seeds in the ground.

Actually, straw bale culture is not “new.” I wrote, over a decade ago, in my book Weedless Gardening, “Straw bale culture of vegetables originated in Europe from a need to grow plants where diseases had built up in greenhouse soils. The idea is to set a bale of straw on the ground and grow a plant right in the bale. You do this by poking a transplant into a hole gouged in the top of the bale and sprinkling some fertilizer on it. Given adequate water and nutrients, the plant roots grow throughout the bale, hardly realizing that they’re not in real soil. There’s no reason why this method could not be used to start a small garden anywhere. Put some paper down on the ground and create mulched paths between the bales.”

Yes, the method could be used “anywhere,” but there are also good reasons not to. First, straw bale culture is not really organic. With this method, plants are fed mostly by soluble fertilizers sprinkled on the bales. The essence of organic gardening is to feed the soil which, in turn, feeds the plants. Plant foods are released from the soil matrix through microbial action. Microbes respond, as do plants, to warmth and moisture, so nutrients become available to plants in synch with plant needs. In straw bale culture, roots are bathed in readily available nutrients whether they want them or not.

Barring diseased soil or trying to garden on a rock ledge, why use straw bale culture in the first place? What’s wrong with dropping a seed in waiting furrow in the ground? 
Not that I’m that rational a gardener, especially this time of year.

I’ve admonished many a person to begin with a site that needs a plant, determine what plant would do well with those site conditions, and then -- and only then -- to go out and get the plant or order it. All that’s
opposed to wandering into a garden center this time of year, when such places are awash with all sorts of desirable plants, picking out a plant you like, and then running around the yard with it trying to decide where to plant.

I, of course, did the latter. A couple of weeks ago, I read about Concorde pear, notable for having “the beautiful shape and crisp texture of the Conference, which gives it an elongated neck and firm, dense flesh. Its flavor is vanilla-sweet, reminiscent of the supple sweetness of Comice pears.” (Supple sweetness?)

The plant is readily available in Britain, but not here. All of which made it all the more desirable. Did I really need a Concorde pear tree? Aren’t the more than 20 varieties I now have sufficient? Evidently not.

As luck would have it, a nursery an hour away had Concorde. The nursery, of course, had  many other desirables also. So I also bought Black Gem, a named variety of black walnut. Not that there aren’t plenty of wild black walnuts around here, but this was a named variety.

So today I will run around the yard with these two plants trying to decide where to plant them.

The appeal of Black Gem is that it has a name. A “named variety” of plant is one that was either bred or selected from a wild population and found to be superior in one or more ways. Said plant is given an official name and then reproduced by some method of cloning, such as by cuttings or, as is the case with most fruit
and nut trees, grafting. McIntosh is a named variety of apple. Seedling apple trees that pop up randomly along roadsides are not. All plants of the same variety name are genetically identical.

Named varieties are not available for every plant and, for some, pretty much all seedlings are quite good. The hedge of Nanking cherries along my driveway -- and now in bloom! -- are merely seedlings, but all the plants are beautiful and yield, in a couple of months, great quantities of tasty cherries with virtually no effort on my part. No varieties are available.

Black Gem, according to the tag, yields “huge crops of light-colored, high-quality, delicious nuts that crack in large segments and offer a superior nutmeat-to-shell ratio. Thin husks slip off easily.” How could I resist?

Friday, May 3, 2013

Loving Locust

With a bit over 2 acres of land to play around with, I could have a woodlot. But I don’t. (I do harvest a lot of sunlight, though.) Still, because this is what I call a farmden (more than a garden, less than a farm), trees, aside from fruit trees, have to fit into the picture. To wit, four sugar maples planted  in 1997 as a sugarbush for tapping in another 20 years and my locust mini-grove.

Locust -- black locust, Robinia pseudoacacia, that is -- is a tree of many qualities. For starters, the roots can garner nitrogen from the air and put it into a form the tree can use, eventually putting it in the soil. Black locust also laughs off heat, drought, air pollution, and road salt. The tree’s craggy branches and deeply furrowed bark are fondly reminiscent of those trees that hugged Dorothy on the yellow brick road to Oz. Towards the end of next month, chains of pale lavender blossoms will be dangling from the branches. More than just pretty, these flowers fill the air with a sweet aroma that carries far.

What more could one ask from a tree? Wood! Some of which I was harvesting from my locust mini-grove last week. The grove is a stand of locusts of various ages popping up in a swathe about 15 feet wide by about 60 feet long. Forsythia shares that space as understory, new plants developing wherever canes arch to the ground to root. The locust grove formed naturally from a long-gone nearby grove on a neighbor’s property, felled by chainsaws, the new plants arising from dropped seeds as well as from root suckers.

Locust is one of the best woods for burning, but cutting trees from my mini-grove for firewood would hardly be worth it. One week in winter would decimate the small patch.

The locust I cut is destined for posts. Locust is one of the most rot-resistant woods, putting even cedar to shame. It can outlast pressure-treated wood, offering a nice rustic look to boot. Spring, before the leaves come out, is a perfect time for cutting locust for posts because that’s when the bark peels off easily in long strips.
The locust posts are for a new grape trellis. My grapes started out being trained to the traditional 4-arm Kniffen system, on two wires, one at 6 feet and the other at 3 feet from the ground. Two canes, originating near a central trunk, are trained horizontally in either direction along each wire to give a total of 4 canes each shortened to about 10 buds long. (A “cane” is a one-year-old stem.

The 4-arm Kniffen system has its limitations in terms of exposing the vine to maximum light, which translates into better-tasting grapes, and keeping foliage and berries dry, which translates into less disease.

So,a few years ago I morphed the vines to the high wire cordon system. A trunk about 6 feet high branched into two permanent arms (cordons) that travelled in opposite directions along a wire at trunk height. In this case, instead of being left with 4 long canes after pruning, the vine is left with many short canes drooping downwards right off the cordons.

We bag some of grape bunches to foil the birds and the bees, as well as other pests. Bagging also lets fruits hang on the vine longer without damage and so develop sweetness and aromatics that make for finest flavor. The problem with the 4-arm Kniffen and high wire cordon systems of training are that the fruiting shoots droop downwards, which makes bagging difficult and puts the bags at an angle that defies gravity, not a good thing. Which is why my grapes have morphed again, this time to a 5-wire trellis system.

The latest incarnation of grape support consists, then, of sturdy T-trellises spaced 10 feet apart. Running perpendicularly to the cross-arms of the T are 5 wires, the middle one to support 2 cordons growing off horizontally in opposite directions atop each vine’s 7 foot high trunk. The other wires will support the fruiting shoots that grow from short canes along the cordon perpendicularly to the outrigging wires. The more horizontal growth of the fruiting shoots should make bagging easier.

So it’s locust wood from my mini-grove that will deserve some thanks for luscious grapes.

Not everyone is as enamored with black locust as I am. Many classify it as an invasive plant; here in New York, I’ve seen it classified as a native invasive plant. It originated in southeastern U.S. but now ranges far and wide because of its fecundity and it’s tolerance for a wide range of conditions below and above ground. The tree’s beauty and utility have also contributed to its spread, by humans.

My only beef with black locust is with its thorns. Still, I like my black locusts and I like my grapes.